beneficial insects

Study Confirms Neonic’s Deadly Harm to Birds as EPA Ignores Facts


The American Bird Conservancy (ABC) recently released an updated, piercing report that confirms the continual decline of wild birds — as well as beneficial insects and many other animals — due to the uncontrolled use of highly toxic neonicotinoid pesticides. It’s a lengthy read, so I thought I’d offer a fairly brief synopsis to those who appreciate and support biodiversity.

Back in 2013, the ABC produced its ground-breaking paper, “The Impact of the Nation’s Most Widely Used Insecticides on Birds” (Mineau and Palmer 2013), which warned of the catastrophic risks that these ambulant and persistent insecticides create for both terrestrial and aquatic ecosystems, as well as the likely repercussions on wildlife who depend on those ecosystems.

Fast forward ten years, and “Neonicotinoid insecticides: Failing to come to grips with a predictable environmental disaster” (Mineau and Kern 2023) reveals that little has changed, except that the quantity used is hidden from us. The report examines the recent science that echos earlier alarm calls and describes the completely inadequate regulatory response by the EPA and other regulators. According to Hardy Kern, one of the study’s authors, “Some states and agencies have taken minimal actions, but we have a long way to go before these chemicals are no longer a threat to birds, native pollinators and aquatic systems.” A recent comprehensive study in Europe found pesticide and fertilizer use to be “more dramatic than forest alterations, urbanization, and climate change”.

Developed by Bayer and Shell and introduced in the early 1990s, neonicotinoids (“neonics”) have been touted as safe and more benign than any previous pesticide groups. They quickly became popular in pesticide markets worldwide and today they are the most commonly used insecticides (where they haven’t been banned). The neonics group is a synthetic neurotoxin chemically similar to nicotine and includes acetamiprid, thiacloprid, thiamethoxam, clothianidin, imidacloprid and others. They are widely used in agriculture (more than 140 types of crops, including rice, wheat, corn, sunflowers, cotton, nuts, soybeans, fruits and vegetables), in commercial nurseries, and in urban areas on golf courses, parks, gardens and lawns, in insect sprays, and flea and tick veterinary products. (Last month, in response to a Center for Biological Diversity legal petition asking that Seresto flea collars — which have been linked to more than 100,000 reports of harm or death — be pulled from the market, the EPA responded by only requiring that warning labels be placed on the collars.)

Neonics are applied as a soil injection (“soil drenching”) and tree injection, as a foliar spray, and as a seed coating (the most common application). As a plant grows, the systemic pesticide permeates all cells within roots, stems, leaves, pollen, nectar, sap, fruit, and honeydew. In addition to killing what are considered pest insects, neonics indiscriminately poison non-target beneficial species like bees, butterflies and other pollinators, including hummingbirds. An estimated 96 percent of land birds are insectivorous and must feed their young insects (which may be poisoned), and seed-eating birds commonly consume spilled seeds loaded with neonic residue. They can also encounter neonics by inhalation of vapors, skin contact, and in their drinking water. Dust generated from pneumatic seed planting machinery can also kill flying insects directly, and it can disperse off-site at seeding time (making additional plants acutely toxic), and contaminate soil. In the soil, neonics persist for months to years, with drift, irrigation or runoff carrying them long distances, eventually contaminating new soil, plant life and water supplies. Only two to five percent of most seeds coated with neonics make it into a target plant, leaving roughly 95 percent in the soil, where it can contaminate the nests of native ground-nesting bees (70 percent of native bees nest in the ground).

When consumed in lethal doses, neonics permanently bind to nerve cells, which typically causes uncontrollable twitching and shaking followed by paralysis and eventually death. But even small, nonlethal doses can cause severe debilitation to victims’ immune, reproductive, navigation, and nervous systems. Birds may become so incapacitated that they don’t eat, migrate, reproduce, and become paralyzed or experience seizures. Researchers have found destructive reproductive effects at concentrations much lower than the thresholds set by regulators: The ABC found that ingesting just one-tenth of a contaminated corn kernel (with any of the neonics) per day during egg-laying season can negatively affect bird reproduction. Appallingly, “A single corn kernel coated with a neonicotinoid can kill a songbird. Even a tiny grain of wheat or canola treated with the oldest neonicotinoid, imidacloprid, can poison a bird.” The ABC authors expressed, “Based on recent studies, we have increasing concerns over reproductive and sub-lethal effects resulting from low exposures in farm fields … Given that exposure is often season-long, this raises the specter of significant effects on a large number of bird species.”

Due to widespread use, neonics have caused and continue to cause extensive ecosystem contamination, including watersheds, groundwater, and irrigation water. Neonics’ water solubility means that they travel easily in surface runoff, contaminating aquifers and other aquatic environments—residues have even been found in seabirds’ feathers and raptors, and there is proof that they kill fish and other aquatic animals. A U.S. Geological Survey study found that neonics polluted more than half of the streams in the U.S. In addition, bats are directly and indirectly harmed, and birth defects have been found in white-tailed deer. If you’re wondering about harm to humans, the NRDC’s “Potential Risks to Brain and Sperm” article details the health impacts, including the possibility of creating even more toxic compounds when neonics are mixed with things like chlorine at water treatment plants. The good news is that organically-grown foods are mostly neonic-free.

Unwillingness of regulators
Regulation of these chemicals is extremely inadequate. The ABC authors say, “The U.S. is far behind the European Union and a few Canadian provinces in responsible regulation and mitigation. The main uses of neonicotinoid insecticides go against fundamental principles of integrated pest management. Alternatives to these chemicals do exist … We believe they have failed in the execution of their mandate and in preventing the ongoing environmental tragedy that neonics represent.”

Possibly the worst debacle of regulators is that seeds coated with neonics are not regulated at all; they’re included in the “Treated Item Exemption” of the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA), which, according to the ABC authors, means that most neonic applications are not counted in usage estimates. In 2017 a number of NGOs petitioned the EPA to remove seed treatments from the exemption. It took the EPA, which ignores the advice of its own scientists, five years to deny it. Earlier this summer the groups sued the EPA.

The U.S. government has also lessened the amount of data available about pesticide use and proliferation to scientists and the public. Earlier this year the U.S. Geological Survey cut the amount of data it collects in its National Pesticide Use Map, and beginning in 2024 its report will be released only every five years, instead of yearly. It’s also shrunken the number of pesticides it monitors from 400 to 72, partly because the USGS purchases data from a private company, which stopped including seed treatments in usage stats around 2015. The USGS says that “seed coatings are too difficult to reliably source information on and, therefore, are not included in national pesticide-use estimates.” They’re also left out of National Water Quality Assessment maps.

So, no one knows how much neonics are used on seeds. A USGS graph of clothianidin usage in the 2023 ABC report shows that over 3.5 million pounds were used in 2014 (mostly on corn), and in 2015 the usage was slightly more than 500,000 pounds. Of course this doesn’t mean that less clothianidin was used; only that seed treatments were dropped from estimated use.

A 2019 study found that U.S. agriculture is nearly 50 times more toxic to insects than it was 25 years earlier and neonics are responsible for a whopping 92 percent of that atrocity—this is especially heinous considering the “insect apocalypse” that experts predict. Despite their rampant use, neonics can actually make pest problems worse because not only do they kill beneficial wildlife; they also kill soil microbes that improve plants’ health, durability, and crop yields. And, there is even evidence that neonics reduce crop production. In the U.S., there is no law that requires manufacturers prove that their product works. Speaking with National Geographic, Kendra Klein, study co-author and senior staff scientist at Friends of the Earth U.S., said, “We have four decades of research and evidence that agroecological farming methods can grow our food without decimating pollinators.”

Are neonics the new “Silent Spring”?
North America lost more than three billion birds (even species once considered common) between 1970 and 2018 — 29% of 1970 abundance — due in part to the ubiquitous use of neonics. Even the EPA confirmed that the use of imidicloprid, clothianidin, and thiamethoxam) harm roughly 75 percent of all endangered plants and animals. According to the Center for Biological Diversity, there’s been horrendous harm to imperiled species by all three insecticides, such as “all 39 species of endangered amphibians, including the California red-legged frog, as well as rusty patched bumblebees, whooping cranes, chinook salmon, northern long-eared bats and orcas.” The American bumblebee, once the most commonly observed bumblebee species in the U.S., has declined by an estimated 89 percent in just the past 20 years. Clearly, neonicotinoids are one of the most dangerous, toxic classes of pesticides that pose atrocious longterm threats to biodiversity. We’re in the midst of a harrowing extinction crisis with beneficial insects, birds, aquatic life, and mammals dying off in appalling numbers and neonics are a major, reckless threat that the earth does not need. “Neonics may not bioaccumulate in organisms and biomagnify in food webs as did DDT and other organochlorine pesticides of old, but they appear to be as widely distributed in the broader terrestrial and aquatic environments,” according to the ABC report’s authors.

Neonics are mostly banned in the EU (even “emergency” uses have been overturned in court) and parts of Canada (Ontario and Quebec require a prescription to use neonics to coat seeds, which has drastically reduced their use). Although a few states in the U.S. have passed legislation that drastically restricts the use of neonics (but doesn’t eliminate them), and other states are beginning to take action — such as Washington’s ban on residential use — only severe restrictions by the EPA will protect ecosystems, biodiversity and human health from these noxious, unnecessary chemicals before it’s too late.

In July of this year, Oregon’s Senator Jeff Merkley introduced the Pollinator-Friendly Plant Labeling Act, which would require the Department of Agriculture to create a certification program for plant producers to certify that their plants are not treated with pesticides or substance not approved for use in organically-grown products that are harmful to pollinators. Producers who choose to participate in the program would be able to use a “USDA pollinator-friendly” label on their plants and products. It’s a minor action, but is a step in the right direction.

In the home garden
The Northwest Center for Alternatives to Pesticides states, “Neonicotinoids are found in hundreds of products sold over the counter under various trade names. Many of these are designed for individual home and garden use. One of the most toxic neonicotinoids to our native bees — imidacloprid — is commonly applied to gardens, flowerbeds, shrubs, and trees in urban and residential areas.” According to the Xerces Society, “even when used according to printed instructions, garden products containing neonicotinoids can be applied to plants in concentrations dozens of times greater than on farm crops [sometimes at concentrations of as much as 120 times]. This means that bees can be exposed to lethal doses of neonicotinoids in gardens. Even if bees are not killed outright, smaller (non-lethal) doses can impact their health.” Remember that labels do not indicate that they are harmful to pollinators, so it’s important to either not buy such products or be sure to read ingredient lists (Imidacloprid, dinotefuran, clothianidin, and thiamethoxam are all neonics found in garden products). This Xerces Society brochure explains how to protect pollinators from neonics.

What you can do:

  • Buy organically-grown foods, seeds, bird-friendly coffee, and other products whenever possible (they’re not always much more expensive). If feasible, grow some organic produce at home. Find a list organic seed companies here.
  • Shop at plant nurseries that don’t use neonics (always ask if you’re unsure).
  • Don’t buy/use products that contain neonics (be sure to read labels).
  • Create pesticide-free, safe outdoor spaces using regional native plants that will encourage wildlife such as native bees, butterflies, birds, and other beneficials.
  • Ask your state and federal legislators to advance laws that eliminate (or at least severely restrict) pesticide use.
  • Email the EPA to voice your concerns about the lack of regulations on pesticide-coated seeds: pesticidequestions@epa.gov
  • Watch Beyond Pesticides’ short video for more info on toxic seeds and check out ABC’s fact sheet.

© 2023 Eileen M. Stark

Posted on by Eileen Stark

More Than Flowers: How to Support Pollinators in All Their Life Stages

Many pollinators are in steep decline and in dire need of protection. A black-tailed bumble bee (Bombus melanopygus) feasts on hairy honeysuckle blossom (Lonicera hispidula).
Black-tailed bumble bee (Bombus melanopygus) forages on hairy honeysuckle (Lonicera hispidula).

On the heels of National Pollinator Week — when we honor the hard-working animals who give so much, let’s remember that they need much more than flowers to survive. These fascinating creatures — from bees and beetles to butterflies and moths — face seemingly insurmountable threats, including habitat loss, the climate crisis, and pesticide use. It’s tragic and overwhelming, but there is much that each of us can do as individuals, and together we can have a tremendous influence over potential habitat in everything from tiny urban lots to community gardens to large rural expanses.

Modern landscaping practices essentially strip habitat from our yards. But there are many easy DIY habitat features that can be incorporated — or simply left in place — and they are superior to artificial supports (such as bee hotels) because they break down fairly quickly (which minimizes parasite and disease problems that come with repeated use), and better imitate the natural density of nest sites that keep pollinators healthy. 

In my Pacific Northwest yard I offer a variety of native trees, shrubs and perennials throughout, as well as a mini-meadow where locally native perennials — such as western columbine, fleabane, checker mallow, blue-eyed grass and iris — grow and buzz with life. To be certain they will return next year, I also provide adequate shelter for overwintering and nesting. I leave leaf “litter”, hollow and pithy stems, and dead wood lying around, provide water and brush and rock piles, use no chemicals, and refrain from doing any “clean up” until late spring, to prevent disturbance of overwintering adults, eggs, larvae, or pupa that may be camouflaged within nature’s debris—for example, the strikingly beautiful western tiger swallowtail butterfly may overwinter as chrysalis (pupa), which looks like a little piece of dead wood during that time. 

At home, here are a dozen easy things we can do to support a variety of pollinators, from bees, moths, and butterflies to beetles and flies. 

~ Leave parts of your garden a little “wild.” Undisturbed shelter and nesting locations are absolutely essential, and gardens that are a bit messy and provide brush and log piles, mounds of rounded stones, as well as patches of bare, well-drained, undisturbed soil will help.

Put away that leaf blower and allow fallen leaves, twigs and bark to remain undisturbed on the ground so that butterflies and moths can make it through the winter either as eggs, caterpillars, chrysalises, or adults, and so that bees such as queen bumble bees can slumber peacefully under a leafy blanket; leave a very light layer on any lawn you have, too. Besides pollinators, many other wild ones live or overwinter in leaves, including beetles, spiders, snails, and worms, all of which are beneficial and/or support the birds, small mammals, reptiles and amphibians who need them for food. An added benefit is that detritus from trees and shrubs insulate plants’ roots, suppress weeds and retain moisture just as well as wood chips or other mulches (that may contain invasive species) but allow for ground-nesting.

For the numerous species of native ground-nesting bees (70% of bees nest in the ground in burrows), supply a generous amount of undisturbed and bare soil. Avoid tillage and anything that prevents access to soil, like plastic mulch, landscape fabric, or thick layers of mulch, including wood chips and bark mulch. Natural fallen (whole) leaves, small pebbles, and light layers of compost are fine. If you must remove some leaves in the spring, wait until late spring to prevent disturbance to species who emerge fairly late.

Nest sites for the other bees that nest aboveground — in stems or tunnels within decaying wood — can be augmented by placing hollow or pithy stems, or downed wood (with or without dead-ended, narrow holes drilled into them) on or above the ground. Bumble bees typically nest in pre-existing cavities such as bird nest boxes, abandoned rodent burrows, unmortared rock wall crannies, hollow logs, beneath bunch grasses, etc. We once had a bumble nest in a small pile of lawn that had been removed and was decomposing upside-down.

In perennial beds, leave flower stalks, branches (and seed heads, to provide food) standing over the winter. In early spring, dead flower stalks may be cut back to create cavity nest sites just before the first bees emerge; naturally-occurring open stems should be left in place. Cut hollow or pithy stalks at a variety of heights, about one to two feet above the ground to supply vertical nesting opportunities for insects of various sizes. You can also bundle together additional cut stalks and place them, vertically or horizontally, in a sheltered spot to create additional nesting opportunities. Female bees will find them and create individual nests, each supplied with pollen/nectar balls upon which larvae will feed. As summer progresses, new growth hides the stems which contain the developing larvae/pupa. Adults hibernate during winter and emerge the following spring and the process starts all over.

Deer browsing may create nesting sites for some cavity nesters and shrubs may be pruned (just before the shrubs break dormancy) to mimic it. However, before cutting any branches, always be certain that no birds are using the shrub for nesting.

~ Provide clean water. Pollinators and other insects need a shallow source of clean water where they can drink and find water to create their nests. Fill a plate or shallow dish with clean pea gravel and keep it moist and near flowering plants.


~ Moisten sand or loose soil to help adult butterflies. Butterflies and moths ingest liquids like flower nectar from which they obtain sugars, minerals, and other nutrients. But they also need to “sip” from muddy or sandy puddles, sap, decaying fruit, sweaty humans, even manure piles to hydrate themselves and obtain dissolved minerals, including salt. Such minerals are vital for many physiological functions, including reproduction: Males often transfer “nuptial gifts” of sodium and amino acids to the female during mating (along with other donations). Before you say, “He shouldn’t have,” consider how evolution toward generosity might generate rewards: More gifts mean more nutrition and better egg survival. To assist, add a dash of salt to containers or areas of moist sand or soil, to be sure they get what they need.

Butterflies and moths often obtain nutrients and moisture in mud puddles, but they’re also attracted to perspiration on skin, like this green comma butterfly.
Butterflies and moths often obtain nutrients and moisture in mud puddles, but they’re also attracted to perspiration on skin, like this green comma butterfly.


~ Steer clear of pesticides. Even those approved for organic gardening, such as rotenone, are harmful. Systemic insecticides like neonicotinoids (a class of insecticides such as imidacloprid, acetamiprid, clothianidin, dinotefuran, nithiazine, thiacloprid and thiamethoxam that affect insects’ central nervous systems), are absorbed by plants and produce toxic nectar and pollen. Studies show that residues may persist in woody plants for up to six years following application and may persist in soil for several years. Herbicides and fungicides can also be harmful. In a healthy, balanced system there should be no need to resort to poisons.

~ Allow some “pests.”
Some pollinators’ young feed on insects that we consider pests, so don’t be too quick to destroy them. Many syrphid flies, which are great pollinators, lay their eggs in or close to aphid colonies, so that their legless and blind larvae can feed on them. Highly efficient, one larva may eat hundreds of aphids. They also may feed on scale insects or thrips. When mature, larvae go to the soil to transform into pupae and eventually into adult flies. Their life cycle takes 2 to 4 weeks to complete. Other syrphid fly larvae are either (1) scavengers that tidy up ant, bee, and wasp nests, (2) feeders of plant material, tree sap, and fungi, or (3) decomposers that feed on decaying organic matter, so yet another reason to not disturb soil too much and to leave plant debris where it falls to the soil.

Syrphid fly laying eggs on an aphid-infested kale plant.

~ Grow a variety of plants that are native to your area, and you won’t need to think too much about whether you will provide food for pollinators. Studies show that native plants are four times more alluring to pollinators than exotic flowers.

Small female mining bee (Andrea sp.) gathers pollen for her young on showy fleabane (Erigeron specious).
Small female mining bee (Andrena sp.) gathers pollen for her young on showy fleabane (Erigeron speciosus).

Got lawn? Whether you have a large or small lot, consider replacing or minimizing turf with native grasses wildflowers, and perennials (and mosses in shady areas). Add native shrubs and trees to provide cover and protection, especially for ground-nesting bees, as well as the fallen debris and brush/log/rock piles mentioned above.

~ Grow butterfly host plants. To become adults, butterflies in earlier life stages — egg, larva, chrysalis — require host plants that provide habitat and food. Find out which butterflies frequent your area, and grow the plants that provide for all their stages. In the Northwest, check out this handy guide: Create a Butterfly Garden (OSU).

~ Provide nectar and pollen in a variety of flower colors, shapes, and sizes for pollinators with different needs. Flower nectar, produced in glandular organs called nectaries, is high in carbohydrates and serves to attract pollinators to distribute plants’ pollen (and in some cases, attracts protectors like parasitoids and ants—which also pollinate to a small extent—against herbivores that may be problematic). Pollen is a highly nutritious blend of proteins, lipids and carbohydrates. We’ve been taught that bees tend to prefer yellow, purple, and blue flowers — anything but red, which they can’t see — while hummingbirds can see and do use reds (although one study suggests that their preference may not be innate, but rather they choose them since bees don’t). While this is true, a 2016 research study shows that bumblebees (and probably other pollinators) choose a plant for the nutritional quality of its pollen, not only its color; they need pollen with a high protein to lipid ratio (which makes sense, since pollen is mainly used to feed their growing larvae). And, research from UC-Davis suggests that pollinators choose among flowers based on the microbes within those flowers, such as yeasts that are “commonly found in flower nectar and … [are] thought to hitch a ride on pollinators to travel from one flower to the next. Yeasts’ scent production may help attract pollinators, which then help the yeast disperse among flowers.” But flower shape and size also matter: Butterflies need clusters of short, tubular flowers with a wide landing pad, such as yarrow (Achellia millefolium occidentalis), various native bees need different types of flowers (generally shallow), while hummingbirds like relatively large, tubular, or urn-shaped flowers.

Syrphid fly (Scavea pyrastri) on western bleeding heart (Dicentra formosa).
A syrphid fly (Scavea pyrastri) on western bleeding heart (Dicentra formosa).


~ Keep it blooming. From spring through fall, something should always be in bloom, preferably several species at a time. In the Pacific Northwest, early spring flowers, like those of osoberry (Oemleria cerasiformis), willows (Salix spp.), and red-flowering currant (Ribes sanguineum), are particularly important to bees emerging from hibernation, while late-season nectar sources such as asters (Symphyotrichum spp. or Aster spp.) help bees that overwinter as adults get through the winter. Both early and late forage may aid in bees’ reproduction. Of course, mid-summer flowers are important, too! Many native species bloom for extended periods, such as charming foamflower (Tiarella trifoliata), which may produce flowers from spring to late summer, white spiraea (Spiraea lucida), and showy fleabane (Erigeron speciosus). Learn when plants bloom to be sure you’ve got it covered, and aim for some overlap in bloom times. Remember that trees and shrubs, as well as perennials and annuals, can provide nectar and pollen. Arrange smaller plants in irregular clumps or drifts so that plants are next to or within a few feet of another of its kind, to supply enough forage and to make it easy for pollinators to find them. Provide at least three different plant species per season of bloom whenever possible.

~ Forgo hybridized and “double” flowers. When choosing nonnative plants, keep in mind that hybridized varieties may lack sufficient pollen nutrition. Pollens vary in protein content, and bees and other pollen-consuming insects need a wide variety to fulfill their protein requirement. Research also suggests that some commonly used garden plants, especially those hybridized for features valued by gardeners, like disease-resistance or flower size or color, may not provide sufficient or appropriate nutrients in nectar, needed for carbohydrates. Frilly double-flowered varieties (those with extra petals that make a flower look inflated and flouncy) are usually inaccessible to pollinators simply because they can’t get through the mass of petals to the nectaries. It’s a bit sad to watch a bumblebee, desperately trying to get inside an overly dressed flower, fly away without food.

~ Turn roadsides native. Studies show that native pollinators are much more prevalent in native stretches of roadside habitat — often the only connection between patches of remnant habitat — than weedy, nonnative stretches. If you own rural land, plant natives near your roadside and mow it very infrequently (from the inside, out) to prolong bloom and prevent harm to creatures who may be taking cover within it.

Other things we can do for pollinators include participating in “citizen science” projects that seek input from gardeners, and advocating for an end to pesticide use in our parks and communities.

Trichodes ornatus
This beetle (Trichomes ornatus), on wild buckwheat (Eriogonum sp.), is a member of a very diverse group of pollinators that are especially important in areas where bees aren’t common.



© 2017 Eileen M. Stark  |  updated 2020

Adapted from content originally published in my book, Real Gardens Grow Natives: Design, Plant, & Enjoy a Healthy Northwest Garden.

 

Posted on by Eileen Stark

Pacific Northwest Native Plant Profile: Red-flowering Currant (Ribes sanguineum)


Although red-flowering currant (Ribes sanguineum) is a deciduous shrub, it offers year round appeal and habitat, making it a favorite among Pacific Northwest gardeners and wildlife, alike. Not one December goes by that I don’t marvel at its ability to hold onto many of its seasonally colorful leaves until the solstice or beyond, and this year was no exception. Just a short while later — following barely two months of downtime in the new year — strikingly gorgeous flower clusters burst forth prolifically at the same time that fresh leaves emerge. No wonder another of its common names is “winter currant.” Fast forward a few more months, and dark dusty-blue berries, a favorite of many bird species, will adorn this multi-stemmed shrub. 

The sole genus in the Grossulariaceae family, Ribes means ‘currant’ in medieval Latin. One of about 30 currant and gooseberry species in the Northwest, sanguineum refers to the reddish color of the flowers. It’s one of those native plants that had to be chaperoned by Scottish botanist David Douglas to Britain—where it was introduced into cultivation in the 1820s—before it acquired a return transatlantic ticket to popularity with gardeners on its home turf. Not too small or huge, it can usually find a home in places that offer well-drained soil and at least a quarter day of sun.

How it grows
Red-flowering currant naturally occurs at the edge of forests as well as open, rocky slopes and disturbed sites, at low to middle elevations from southwest British Columbia into Washington and Oregon between the Pacific coast and the Cascades, and as far south as central California.

Wildlife value
Pendulous flower clusters, which consist of numerous lightly fragrant, pink to reddish tubular flowers, bloom in profusion along this shrub’s many stems. They offer nectar and pollen at a time when early-emerging pollinators—such as queen bumble bees who must secure a nest and provide for offspring all by themselves—have little else to eat. The early blossoms are also attractive to birds, especially hummingbirds, but also bushtits, making this species a hub of wildlife activity for well over a month. Later on, when berries ripen as summer wanes, birds such as American robins and cedar waxwings (pictured, below) feast; we can also eat them but they are rather tasteless. The small, lobed leaves may provide food for zephyr (Polygonia gracilis zephyrus), Ceanothus silkmoth (Hyalophora euryalus), and other butterfly and moth larvae, which in turn supply food for insectivorous birds. 


Try it at home
Red-flowering currant prefers sun to part sun, and well-drained soil. While tolerant of clay soils, it doesn’t do well on poorly drained sites. Useful for erosion control on slopes, it may eventually form a thicket, which is helpful for wildlife that needs somewhat dense cover.

Mature size varies from around six to ten feet tall; width is typically similar, so do allow it plenty of space so pruning won’t be necessary. A fast grower, it may reach four or five feet in just a few years and even produce blossoms as well. If you’re looking to use this shrub in a border, space them six to ten feet apart (on the low end if you want some density and overlap). Although this shrub is quite drought tolerant when established (after two to three years), water it deeply but infrequently in the hot summer months thereafter, especially if your site receives a lot of sun or reflected heat from buildings or fencing, or if drainage is quick. Plant in fall for best results.

The only downside to this lovely shrub is its relatively short life: typically just 20 to 30 years. But replacement is easy since it readily self-sows. Thus, propagation is best achieved simply, via self-sown seed, which are easily dispersed by birds or fall to the ground below. If you’d rather DIY, collect seeds as soon as fruit is ripe in mid to late summer, remove the pulp, and dry them in a shaded place; then sow in autumn (outdoors to allow for stratification). Seed reportedly has a long shelf life if stored in a cool/dry/dark place.


Grab a partner
Since red-flowering currant grows in a fairly wide range of habitats, there are a number of plants with which it interacts in intact ecosystems. For best ecological and gardening results, choose associated native plants that live in communities that currently grow or likely would have grown in your immediate area. In the Pacific Northwest, some of the plants that red-flowering currant closely associates with include Douglas-fir, bigleaf maple, madrone, bitter cherry, oceanspray, vine maple, elderberry, mock orange, serviceberry, manzanita, salal, sword fern, kinnikinnick, and others. 

Buy plants propagated from source material that originated as close as possible to your site. Using such “local genotypes”  helps ensure that you get plants that are well adapted to your area and preserves the genetic diversity that helps plants (and animals) adapt to changing conditions. Ask growers and nurseries about their sources if you’re unsure.

Although many cultivars—with a range of flower color—have been developed, it’s best to choose true species or varieties found in nature. A related species for very moist places is wild gooseberry (Ribes divaricatum), which has edible fruit.

© 2019 Eileen M. Stark

Posted on by Eileen Stark

Welcome Little-Known Moths to Your Garden

Smerinthus jamaicensis


The little sphinx moth caterpillar was on a mission: To find a safe, secure spot where she could transform herself and stay alive during the cold, wet winter months ahead. On a warm September day last year I watched as she inched her way across half the length of my back yard, occasionally meandering around roadblocks like plant stems and small rocks that must have seemed like insurmountable boulders to her (although at one point she nimbly climbed up and over a small log in her path). A couple of times she burrowed down into loose leaf cover, but then moved on, perhaps surmising that a better place would come along. After I walked away for a few moments I lost track of her. Since my yard is a leafy nirvana for butterflies and moths such as her species (Smerinthus jamaicensis or twin-spotted sphinx) that need to nestle themselves in soil under fallen leaves so they can pupate over the winter months, she probably found a suitable place that would hold her until a warm spring day allowed her to emerge and take to her wings.  

We’re nearing the end of National Moth Week, a short stretch of time set aside to appreciate these gentle, humble, and nimble flyers who tirelessly supplement the daytime work of bees, butterflies, and other pollinators, as well as offer food for other animals. They get a fraction of the attention that butterflies do and are often vilified, despite their close relationship, beauty, and rich diversity. Within their hidden world are unusual, intriguing, and dramatic behaviors. Moth species outnumber butterflies by around ten to one; there are more than 11,000 species in the U.S., with another 160,000 globally. 

Gardens are very important places for moths since development and agriculture severely limit their habitat. There might be dozens of moth species inhabiting an ordinary urban or suburban garden, and the way you manage yours can affect the conservation of their populations, which are, as you might expect, seriously in decline, like most insects. Here are some tips:

Protect them from light pollution. For nocturnal and crepuscular moths, as well as other insects and migratory birds who use celestial navigation, unnatural lighting can cause disorientation and confusion, leading to exhaustion and death. The best way to help restore their natural behavior is to turn off all exterior lights, using motion sensors when necessary. If you must have lights on, use only dim bulbs in warm (yellow) tones, which are less likely to attract moths. Draw shades and draperies indoors as well, to prevent light trespass.

Ease up on “clean-ups”. Adult moths and their caterpillars, as well as some butterfly species including the mourning cloak, need fallen leaves, stems, twigs and other plant debris to help them hide from predators and to provide suitable places to pupate and spend the winter. Let fallen leaves stay on soil and delay cutting back spent plants until well into spring (the later the better), rather than doing it in autumn or winter (and always check branches that may hold a chrysalis). If you must neaten up a portion of your garden in the spring/summer, leave collected plant material elsewhere in your yard.

Forget about herbicides and other pesticides, which can kill moths and other insects. This will also benefit your garden by increasing the number of predatory insects that help control the pesky ones. There needs to be a supply of prey in order to feed the predators—it’s a natural cycle that needs to be supported.

Limit hardscaping (concrete, gravel, decking) and increase the amount of area given to plants other than lawn, since moths and other wildlife can’t use hardscape for habitat.

Grow a wide variety of plants (preferably native species local to your area) to appeal to a diversity of moth species—everything from grasses and flowering perennials to shrubs and trees. Gardening for moths is similar to gardening for butterflies and other pollinators, although moths generally tend to feed on a greater variety of foods than butterflies. 

As adults, most moths need a sugar source and they may feed on plant nectar, rotting fruit, or tree sap. Moth-pollinated flowers tend to be fragrant and pale or white, such as western mock orange (Philadelphus lewisii), oceanspray (Holodiscus discolor), and snow brush (Ceanothus velutinus), which allow nocturnal moths to easily find nectar after dark, so think “moonlight garden”. Moths that pollinate by day typically feed at flowers that native butterflies do, since they usually have long tongues. Some moths, like the twin-spotted sphinx, have reduced mouthparts and digestive tracts so don’t eat at all in their adult stage; they exist briefly only to mate and lay eggs, which in turn may provide food for predators like birds.

Almost all moth species need a host plant on which to feed during their larval stage. Many moth caterpillars eat leaves like most butterflies do, but some species may eat seeds, woody stems, or roots. The most important native host plants for moths and butterflies in the Pacific Northwest — considering the abundance of species they host — include Oregon white oak (Quercus garryana), oceanspray (Holodiscus discolor), and species in the following genera: Acer (maple), Alnus (alder), Arctostaphylos (manzanitas and bearberries), Ceanothus (wild lilac), Populus (aspen and cottonwood), Ribes (currants and gooseberries), and Salix (willows). 


© 2019 Eileen M. Stark

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The Best Mulch is Green

Inside-out flower and star-flowered false Solomon's seal mingle in a mostly shady site.

Inside-out flower and star-flowered false solomon’s seal, both PNW natives, mingle in a mostly shady site.


In an intact ecosystem, nature protects bare soil with native plants (or decaying plant matter) that offer a protective umbrella aboveground and keep soil in place with their roots. In disturbed areas, nature can’t count on the indigenous plants that fell under the plow 200 years ago or were destroyed more recently, so it works with what’s left: Weedy plants brought in, intentionally or not, from other ecosystems or other continents, some of which are so invasive that they destroy wildlife habitat. That’s not a good thing, so we either pull the weeds and leave the soil bare (which can cause soil degradation and exposes more weed seeds to light), or spend many hours every year spreading wood chips, bark dust, rocks, or — heaven forbid — nondecomposable plastic sheeting or rubber mulch to try to keep them at bay. But there’s a much better way that’s good for biodiversity and your back.

Before I get to that, keep in mind that some mulch applications can be beneficial—as in compost applied to veggie gardens that need lots of nutrient-rich organic matter and help retaining moisture, or a couple of inches of aged wood chips to help new trees and shrubs get established. Although a layer of wood chips won’t control erosion on slopes or provide wildlife habitat, it also won’t destroy your soil if it’s not tilled in, so it has its place. Let’s say you’ve planted some new trees. Wood chips spread circumferentially around the trees a little past the drip line will suppress weeds, allow water infiltration, minimize water loss (when applied while the soil is still moist), and encourage microbial soil life (but be sure to keep all mulches at least six inches away from trunks or main stems to prevent rot). However, applying additional mulch in the following years in the same place provides no benefits since the trees’ feeder roots will have grown way past the circle of mulch, in some cases eventually reaching double the diameter of the tree’s canopy (the majority of trees don’t have tap roots). As your plants become established and if they’ve been spaced appropriately and leaf litter is allowed to accumulate, there won’t be a need for any kind of trucked-in or bagged mulch. And, you won’t have to worry about whether your mulch application entombs bees and other insects that nest in the ground.

A low-nitrogen compost, such as leaf compost, ought to be used in place of wood chips, especially in areas where soil is degraded, such as soil that was once trapped under concrete. But remember that thick applications of compost can smother beneficial insects and get in the way of ground cover plants on-the-go, so using whole, unchopped leaves is best for eco-functional, “real” gardens.

The worst offenders
Fine wood chips or bark “dust” tend to compress into a dense, impermeable mat that prevents rainwater from soaking in and may even blow away soon after application. Rock or gravel mulch is devoid of life, adds absolutely nothing to the soil, makes it impossible to add organic matter later on, and in sunny spots will either reflect or absorb heat (depending on the lightness or darkness of the rocks)—not a good thing to do to plants, most of which can’t take the heat. Rock or gravel mulch also make it harder to get rid of weeds and while it might be okay in rock gardens, it is not beneficial for most other plantings and does not prevent weeds. Lastly, any thoughts of using plastic “weed liners” or “landscape fabric” should be quickly consigned to oblivion since they prevent moisture from reaching plants’ roots and soil life, and contribute to the enormous glut of extremely problematic plastic on this planet.

What do wood chips, rocks and plastic have in common? They’re unnatural. Sure, they may keep weeds down temporarily, but they also smother beneficial arthropods that live in or on the soil and make it impossible for ground feeding birds, who instinctively rummage through fallen leaves, to find food. They can never create habitat that plants and animals need. When in doubt, ask “What would Nature do?” Her answer certainly wouldn’t be to finely grind up trees or roll out the plastic and rocks! This image has an empty alt attribute; its file name is Screen-Shot-2025-02-16-at-1.02.20-PM-5.jpg

A living mulch
To add wildlife habitat and connectivity, increase diversity, protect the soil, sequester carbon, mitigate storm water, keep weeds down, and possibly control erosion (depending on the plant species), think green—that is, living, growing plants. What may first come to mind are low, ground-hugging plants, but taller plants also contribute benefits as well. A densely layered, fully planted garden — from ground cover and small shrubs, to tall shrubs and trees — will shade out weed seedlings and minimize the soil nutrients they need, weakening their chances at prospering. It will also be much better at carbon sequestration than lawn or garden beds made up mostly of mulch.

Arrange big trees and the understory — shrubs and perennials — in a layered effect, to create connections and conditions that help to cover the soil. When plants touch one another and overlap a bit, or — in the case of ground covers — cling to the ground and spread (a lot or a little, depending on your needs and the size of your yard) we mimic nature and lessen maintenance tasks. A living mulch looks much better, too. And simply allowing leaves and other dead plant material to stay on bare soil will add nutrients and organic matter to the soil as they decompose.

Placement is important 
Plants are often placed too far apart or are placed appropriately but then sheared into odd shapes, leaving the soil bare. Or they’re placed so that when they reach mature size they grow into walkways or houses and the blame is placed on the plant: The “it’s overgrown” quip often results in plants butchered beyond recognition and loss of habitat. The best placement allows plants to assume their natural shapes and habits and lets them touch and overlap a little, both above and below ground. When we arrange plants so that their roots occupy most of the soil, it becomes more difficult for new weeds to take hold. One caveat! Do leave some soil bare, particularly in open areas, because 70 percent of native bees nest in the ground — they burrow into bare earth like ants do — and they cannot nest in thick layers of loose mulch or thick, lush ground cover. So, don’t cover every square inch of your property; everything in moderation.

Planning for change
When planning your garden and before you draw up a planting plan, it helps to do a birds-eye-view sketch, drawn to scale, with just general plant material or plant groupings. One example: A large tree to shade the southwest side of your house, shrubs that can handle partly shady conditions beneath the tree, and woodland perennials/ground cover plants to blanket the soil. Then choose the plant species that fit the conditions and size constraints. It’s essential to research mature widths as you choose plants (especially shrubs), so that their placement won’t be too close or too far apart. Check at least two sources to be sure and don’t always rely on plant tags, which may or may not be correct (I find that most shrubs get bigger than tags say). For continuous cover, place them a little closer than their mature width apart, giving shrubs and trees enough space so that they don’t infringe on walkways and neighboring properties and such. Try to choose plants that occur in natural communities within your area so that they will be able to communicate through the soil, as well as air, to trade nutrients and secrets that helped them survive together for thousands of years. And while sun-loving plants should be arranged so that they don’t shade each other out, it’s okay to let plants compete a little. For ground cover plants that need shade, allow your larger plants (that will eventually supply shade) to grow a few years before adding the ground cover. Or, start with ground cover that likes some sun, and then replace it later on when you’ve got enough shade. The latter approach works best with slow growing trees like Oregon white oak; the former with speedy growers such as Douglas-fir.  

Sedum spathulifolium meanders along a stone stairway.

Sedum spathulifolium meanders along a stone stairway.

Gardens are ever-changing, just as Nature is, so it should be no surprise when they reject the status quo and slowly transform and shift over time: There may be early successional plants (“pioneer species”) that establish quickly and help to create a quick green mulch that competes with early weeds. After a few years they may give way to the next succession of plants that come later. Plants that move, either by self-sowing or via underground roots, are usually trekking to a place that suits them, and we can learn from their relocations. For example, if you’ve planted a sun-loving perennial in a partly shady spot, you won’t need to think too hard about why it’s sown itself in a sunny pathway. Of course, there will be times when you’ll need to do some editing so that your design continues to please and function well.

Native ground cover to consider
Below are a few low ground cover type plants (those that will spread or self-sow in the right conditions) for the Pacific Northwest (west of the Cascades) in sunny to partly sunny spots and shadier areas. Besides light needs, aways check moisture requirements and find out whether it is native to your specific area. Consider growing several species in the same area so that they mingle into a tapestry that creates texture and prolongs bloom time. Some (*) are quite assertive in certain conditions, so may not be best for small properties. Also keep in mind that most smaller plants will self sow and fill in spaces eventually, such as columbine (Aquilegia formosa) and fringe cup (Tellima grandiflora). Finally, don’t forget about moss in mostly shady places—it’s great on compacted soil and rocks, provides wildlife habitat and nesting material for some birds, sequesters carbon, helps control erosion, and doesn’t need mowing like lawn does. 

For mostly sunny sites:

Arctostaphylos uva ursi (kinnikinnick)
Campanula rotundifolia (common harebell) *
Carex obnupta (slough sedge)
Ceanothus prostratus (prostrate ceanothus)
Erigeron glaucus (seaside daisy)
Penstemon cardwellii (Cardwell’s penstemon)
Sedum oreganum or S. spathulifolium (sedum)
Sisyrinchium idahoense (blue-eyed grass)
Viola adunca (early blue violet)

For shadier, woodland sites:

Achlys triphylla (vanilla leaf)
Asarum caudatum (western wild ginger)
Dicentra formosa (western bleeding heart) *
Mahonia nervosa (Cascade Oregon grape)
Maianthemum stellatum (starry false Solomon’s seal)
Maianthemum dilatatum (false lily of the valley) *
Oxalis oregana (wood sorrel) *
Vancouveria hexandra (inside-out flower)
Viola glabella (stream violet)

Early blue violet (Viola adunca) , a host plant for fritillary butterflies (three of which are listed federally as endangered species), gently self sows.

Early blue violet (Viola adunca), a host plant for fritillary butterflies (three of which are listed federally as endangered species), gently self sows in my back yard.


© 2018 Eileen M. Stark

Posted on by Eileen Stark

Take Care During Fall (and Spring) Garden “Clean-ups”

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(Updated 2025)


The last of the warm, dry fall days are upon us and it seems like a great time to be puttering around the garden. But this time of year is actually not a good time to be “cleaning up”— that is, removing fallen leaves and woody debris from bare soil, pruning standing plants, applying heavy mulch, and making your yard look somewhat like a victim of a gardening magazine makeover. Leaves and other plant material that fall to earth are part of nature’s systems that nurture and shelter wildlife, enrich and protect the soil, and offer many other benefits. Healthy soil has an uncanny ability to not only keep plants thriving, but also store carbon.

Bedtime for bugs
Leaving fallen leaves on soil is one of the best (and easiest!) things you can do to support wild ones such as birds, amphibians, and small mammals in your garden, as well as myriad invertebrates, including bees, butterflies, spiders, beetles, and worms. Leaves and other plant matter are meant to fall to the soil, to provide food for unfathomable numbers of microbes as well as the macroscopic consumers and recyclers that feed on decaying plant matter. Further up the food chain, many creatures — ground-feeding birds, for example — rely on nature’s soil cover to provide for those they need to eat, which they find under leaves and downed wood (fallen twigs and branches, etc.).

Fox sparrow

A fox sparrow finds dinner under leafy cover.

If we zoom in a bit, we might see small organisms, such as syrphid fly larvae depending on plant debris for a sort of blanket to help them through the cold, wet winter. As things warm up in springtime, some kinds of syrphid fly larvae will consume enormous quantities of aphids and leafhoppers that can harm our edible plants. Adult syrphid files (also called “hover flies” or “flower flies”) are important pollinators: Spring through late summer I see quite a variety of them in my garden, probably because I prescribe a healthy dose of fallen leaves on the ground in autumn. But thick layers of wood chips, bark, and other heavy materials can make it difficult — if not impossible — for ground-nesting bees to emerge in springtime. Seventy percent of native bees nest in the ground and heavy mulches can bury them alive. And tilling the soil in areas with ground-nesting insects is another practice to be seriously avoided; tilling also destroys soil microbes.

A leafy layer also encourages other pollinators to make it through the winter. For example, as pollination season shuts down and bumble bee workers (females) and males perish, newly crowned bumble bee queens (technically “gyne,” an impregnated queen who has not yet founded a nest but will establish a whole new generation of bumble bees next year) live on. Queens find refuge by digging a shallow tunnel in loose soil — known as a hibernaculum — that’s often tucked under leaf litter. And, many species of lepidoptera (butterflies and moths) overwinter under fallen leaves as eggs, larvae, pupae, or adults. If we disturb their slumber by blowing or raking them away, they and the ecosystem will suffer. Essentially, the simply need to leave them and their habitat alone if we want them to grace our gardens and wilder spaces next year.

Pupa Western Tiger Swallowtail

Western tiger swallowtail pupa, clinging to wood, waits out the winter and spring.

Don’t cut back
Fall pruning isn’t a good idea because it may stimulate a plant to put on new growth, which could be damaged by the lower winter temperatures soon to come. Another important reason not to prune in autumn is that branches and bark — particularly of native plant species — may support butterfly and moth pupae, (aka chrysalis). Swallowtail butterfly pupae pass the winter attached by thin threads to woody material — disguised as dried up leaves or old bits of wood to fool predators — until the warmer temperatures of spring stimulate their metamorphosis into adults. While some non-native fruit trees do need winter pruning and it’s beneficial to remove diseased and dying annual vegetable garden plants to prevent the spread of disease to next year’s kitchen garden, in all other parts of the yard, if you must prune woody plants, approach it the following spring, being sure not to disturb any nesting birds.

Erigeron speciosus (showy fleabane) seed head. When viewed closely, seed heads can be fascinating in their complexity.

Moreover, although they may look dead, the seed heads of PNW native perennials such as fleabane, fescue, goatsbeard, and lupine provide food for seed-eating birds, while their stems or stalks—pithy or hollow—provide shelter and/or cavity nests for beneficial insects like the wild bees that nest in small tunnels. If you must cut them back to the plants’ bases, do it as late as possible in springtime and, instead of throwing them away, place the cut stems in an out of the way place so that anyone using them to get through the winter won’t be discarded and so that they may be used by the current year’s cavity nesters.

And, aesthetically speaking, allowing fading plants to stand during winter provides structure and form. On cold, frosty mornings they can be magically transformed into silvery jewels.

Protect and nourish the soil
Down at soil level, besides providing a haven for overwintering organisms, fallen leaves and woody debris protect the soil, which can degrade and erode fairly quickly from excessive rain, sunlight, and wind. In nature, soil is protected and mimicking the way it does that will help your soil stay healthy. And over many years, leaves decompose into layers of organic matter that feed plants naturally and gently, improve the condition of soil, and store carbon with the help of mycorrhizal fungi. The other day I relocated a plant to a spot in my front yard that’s been collectively accumulating a couple dozen inches of leaves over the past 15 years. To my delight I found the result of their decomposition: A couple of inches of soft, dark, rich organic matter that wasn’t there a decade ago. 

Even when we’re being careful, though, it’s easy to cause disturbance. Many autumns ago, as I moved a small amount of leaf litter to another area, I inadvertently uncovered an overwintering queen bumble bee. I felt terrible as I watched her stumble around, obviously weak and awoken from a sound sleep. Luckily it was a warm, dry day and eventually she flew off into the sunshine. But clearly the awakening had been a rude one, because a short while later she returned and burrowed into some loose soil covered by leaves, just a few feet from where she had been. After she was safely underground, I gingerly placed a couple of particularly interesting rocks several inches from her tunnel’s entrance, as well as some oak leaves on top of the soil to remind myself of where she slept.

Moral of the story: The more we clean up and work towards a neat and tidy garden, the worse off birds, bugs, and countless other life forms will be. If you tend to be a neatnik (like I am), try to catch yourself every time you start moving into manicure-mode and getting overly tidy—especially in the wilder parts of the yard where wildlife may visit or set up house. It just doesn’t make sense to risk losing them for the sake of neatness or to maintain a certain ‘look.’ If you have piles of leaves that have been raked off hardscape or lawn, here are additional ways to use them in your garden.


© 2025 Eileen M. Stark

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After a Storm: Dead Wood Gives Life

snaggy-stump

Following a particularly nasty ice and wind storm that damaged or took the life of many mature trees in Northwest Oregon, it’s time to clean up nature’s ragged pruning job and literally pick up the pieces. Or is it?

Clean up sparingly
If there are damaged limbs on a street tree or yard tree close to your house, hire a certified arborist to remove any dangling branches and clean-cut any ragged wounds and stubs left by breakage, particularly if you have a tree that is prone to disease, such elm-damage-ice-stormas an elm. Sharp cuts that don’t leave stubs (partially amputated branches not cut back to the branch collar that look like you could hang a hat on it) will allow for faster healing and may prolong the life of the tree. But if safety is not an issue, consider that natural, important habitat is created when damaged limbs are simply left on the tree. As I wrote in my book, “interactions between wildlife and decaying wood are fundamental to ecosystem functions and processes in forests, aquatic habitats,” and your garden, whether they be wooded or more open.

We’re usually far too eager to remove anything and everything that’s fallen to the ground to keep our yards neat and orderly. Unfortunately, this sort of maintenance can be harmful not only to our backs, but also to dwindling
dead woodwild species that need natural, woody “litter” and some disarray, not homogenous expanses of bare soil, bark mulch, or clipped lawn. In fact, “cleaned up” landscapes are usually outright harmful to wild species, including pollinators and recently fledged birds who need low cover to stay safe. Like fallen leaves, “dead wood” or “downed wood” is so essential that many creatures (and plants) cannot survive without it. So, instead of hauling away branches, logs, bark debris, stumps, twigs and such, be compassionate and leave it (or move it to an appropriate, out-of-the-way part of your yard) so that it can decompose naturally to improve soil and begin to provide food, water, shelter, nesting material, or places to raise young.

Decomposing dead wood has many other unnoticeable yet complex eco-functions, like supporting fungi that live in symbiotic relationships with plant roots. Douglas-fir trees can associate underground with as many as two thousand species of fungi during their long lifespans; those fungi make up a major part of soil in forests. Eventually, the stuff that may look messy to us turns into fertile soil which supports plants which support insects which support birds, and so on. 

Snags are a good thing snag at Smith & Bybee lakes
What about dead or dying trees? Known as snags, with their hollow cavities, broken branches, and loose bark, they actually may provide more varied habitat for all sorts of creatures than living trees do! In addition to providing essential housing for many types of insects (including pollinators), cavity-nesting birds, amphibians, reptiles, and small mammals (including bats), they provide food, open perches and double as storage lockers. Woodpeckers also use them to communicate during breeding season.

Snags are in very short supply as forests are increasingly decimated, and they’re extremely rare in urban areas. Removing them not only steals crucial habitat; it’s expensive. Leave snags in low activity areas that won’t pose a problem if they fall apart; when they do fall they’ll continue to give back in the understory. If safety is a concern but you want to retain a dead tree’s benefits, consult with an arborist to shorten its trunk to snag with female flicker feeding youngroughly 15 feet tall and cut back branches. If that’s not possible and you must cut it down, leave the trunk on the ground where it won’t get in your way and leave the stump. If you already have a snag, retain or add native shrubs near its base. They will help keep it protected from weather extremes and provide connectivity, leafy cover, and additional forage for wildlife.

The Washington Department of Wildlife has more detailed info on these “wildlife trees” and the Cavity Conservation Initiative has an enchanting video that documents, up close, the lives that they support.

 

Designing with dead wood
Although some people view snags and other dead wood as unattractive, more and more of us see them as aesthetically pleasing natural sculptures, issued gratis to the landscape and priceless for wildlife. Keep them, work around them, and incorporatesnag "sculpture" them into your landscape, and the wild ones will thank you.

Consider grouping logs and branches in layered piles, with the largest at the base, in quiet places under trees where they can provide shelter from predators and roosting sites for little ones. Fallen trunks or massive logs can recline individually on the ground, where they might act as lovely focal points that will change over time, displaying dead wood (stump)the quiet beauty that unfolds during all stages of natural decomposition and regeneration. Imagine a “nurse log” in your own yard that will increase biodiversity by providing decades of nutrients and moisture to other plants and soil organisms. While natural, moss-furred nurse logs (fallen forest trunks and limbs) provide complex substrates for regeneration of trees in intact forests, there’s no reason you can’t foster similar function in your yard (but never remove nurse logs from a forest!). Surround a fallen giant with local native ferns and other shade lovers to blend and complement, and the mystery and magic begins. It rots slowly at first, then begins to crumble away, providing more sustenance for other species. After a few decades (or a great deal longer, depending on the species), the log will be reduced to nothing but fragments, but the soil—nurtured, enriched, and full of life—will pass on its riches. Fallen logs hold large amounts of water and nutrients like nitrogen and phosphorus and, with time, concentrate those nutrients to provide even more. And new lifeforms such as bacteria, fungi, protozoa lead to salamanders, beetles and millipedes.

A few plant species do best when growing on or next to downed wood. In the Pacific Northwest, Vaccinium parviflorum (red huckleberry), that deliciously berried shrub that hikers know and love, is almost always found growing on a stump, nurse log or other decomposing wood in forests. When I planted red huckleberry shrubs in my yard a few years ago, I buried some rotting wood in the planting hole and added dead branches and conifer cones on top of the soil. So far they seem to like it.

Nest boxes and more trees to the rescue
If you’re like most people and don’t have a snag or a mature tree with decay on your property, consider adding a species-appropriate nest box for cavity nesters like chickadees, chickadee nest boxnuthatches, woodpeckers, swallows, or owls that is sited correctly and is accessible for annual cleaning. Though not as good as natural nest sites due to their inability to insulate as real tree cavities do, boxes are better than nothing.

Lastly, if you’ve lost a tree or have the space for one more, consider planting a regional native replacement (or two or three) that will thrive in the site’s conditions. It’s crucial that we keep planting and protecting, so the cycle can continue.


© 2016 Eileen M. Stark

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Posted on by Eileen Stark

Reimagining the Ecological Value of Cities for Dwindling Pollinators

Bombus vosnesenskii

A recent literature review on the ecology of urban areas published in Conservation Biology offers irrefutable evidence that cities can and ought to be havens for wildlife, specifically pollinators. In “The City as a Refuge for Insect Pollinators,” the authors, a group of multidisciplinary scientists from around the world, recommend that urban areas—particularly fast growing ones—be managed to support biodiversity.

Habitat loss, degradation and fragmentation, industrial farming, wildlife diseases, and widespread use of toxic pesticides have wiped out and continue to wipe out many insect pollinator species. Along with other invertebrates, we really don’t know how many are disappearing from the earth forever, although new studies show horrifying losses. Since urban sprawl is a major reason for the shocking loss of biodiversity, it’s surprising that historically, the consensus—even among conservationists—has been that cities can’t or don’t need to support wildlife. But many years of research on wild bees in urban areas proves that cities can or still do supply habitat for both pollinator abundance and diversity, and “in several cases, more diverse and abundant populations of native bees live in cities than in nearby rural landscapes.”

While we certainly need to also restore and protect rural and suburban lands, there’s a growing realization that “pollinators put high-priority and high-impact urban conservation within reach,” writes the team. “The relatively small spatial and temporal scales of insect pollinators in terms of functional ecology (habitat range, lifecycle, nesting behavior compared with larger mammals for example) offer opportunities for small actions to yield large benefits for pollinator health.” Small actions: they’re talking about you and me, as well as city planners. As the authors note, many residents understand the urgency and necessity, and are willing to help. Turning our yards into “real” Cedar waxwing in red-flowering currantgardens, complete with native plantings and other elements that support entire life cycles of local biodiversity, ought to be paramount. Priceless benefits to us (crop pollination and a chance to admire nature’s beauty), to countless other species that rely on plants or insects for food, and to plants (pollination), come with the package.

Urban conservation often aims to connect people to nature. This is, of course, a good thing, since nature education is extremely important—it’s been said many times that the more we learn about wildlife and natural processes, the more we will want to protect it. But if more effort was spent on wildlife itself and providing what it needs (large, undisturbed, interconnected areas of native flora), no doubt many species would be much better off. I always feel a need to apologize to startled birds and little mammals I encounter on walks in natural areas around the city. There’s a reason wildlife refuges often close off sections to pedestrians: many species are hypersensitive to human presence; they see us as predators and the stress harms them. It would be immensely beneficial if parts of urban areas were also simply left to the wild ones.

I can’t agree more with the authors. If we want to recover and protect pollinators and other wildlife globally, we need to tend to their needs locally. It will take policy makers, planners, and environmental managers, but also each of us, whether we work individually or engage with community organizers.

 

© 2016 Eileen M. Stark

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An Underappreciated Insect: The Syrphid Fly

Toxomerus occidentalis, female slurping nectar on Erigeron specious (showy fleabane)

Toxomerus occidentals (female), soaking up nectar on showy fleabane (Erigeron specious)


Beneficial in many ways, syrphid flies — also called flower flies — are true flies in the order Diptera, family Syrphidae. Some can be recognized by their ability to dart around as well as hover in the air in one place, wings nearly invisible, as they search for flowers on which to feed—somewhat like a tiny helicopter, but with much more grace (this flair led to their other common name, hover fly). They come in various shapes and sizes (typically 1/4 to 3/4 inch in length); the tiny ones require a hand lens or macro lens to get a good look. And when you do, you’ll be amazed at the beautiful patterns and bright colors that often serve to mimic dangerous looking bees or wasps and fool predators like birds into leaving them alone (but don’t worry, they couldn’t sting you if they wanted to!).

Syrphids in the genus Spilomyia often mimic wasps, with vivid yellow and black patterns and modified antennae.

Syrphids in the genus Spilomyia often mimic wasps, with vivid yellow and black patterns and modified antennae.


Multi-functional
Not needing to carry and store pollen for their young (like most bees do) doesn’t prevent them from being extremely important pollinators. Researchers have found that although syrphid flies pollinate less effectively per flower visit, they visit flowers more often, resulting in essentially the same pollination services as bees. And, it’s thought that they may be more tolerant of the landscape changes that we humans insist on, than bees are.

But syrphid flies are not only important as pollinators in gardens, organic farms, and wild areas. During their immature stage, most species that are found in gardens and nearly half of the 6,000 syrphid fly species worldwide are voracious consumers of aphids, scale insects, and other soft-bodied pests. In coastal Central California, researchers compared romaine lettuce sprayed with an insecticide and lettuce without insecticide. They found that syrphid larvae were primarily responsible for suppressing aphids in organic romaine lettuce, and called the sprayed lettuce “unmarketable.” Other types of syrphid fly larvae are either (1) scavengers that tidy up ant, bee, and wasp nests, (2) feeders of plant material, tree sap, and fungi, or (3) decomposers that feed on decaying organic matter. To add to their achievements, larvae are reportedly more effective in cool weather (as in early spring) than most other such predators.

Myathropa florea, male. Larvae feed on bacteria at the base of trees or in decaying leaves.

Myathropa florea, male. Larvae of this species feed on bacteria at the base of trees or in decaying leaves.


Life Cycle
Females lay their tiny, elongated eggs singly on leaves—typically near aphid colonies, so food is within reach—and they hatch in a few days. The tapered, grub-like larvae are blind and legless, but the mouths of these aphid-eaters are equipped with triple-pointed darts that enable them to pierce and suck their prey dry. At maturation, the larvae are promoted to the soil to become pupa and, eventually, adult flies. Their life cycle takes several weeks; reportedly three generations per year are typical in the Northwest. Most syrphid flies overwinter as larvae in leaf litter—yet another reason to not remove fallen leaves from soil!

Close encounters
The best way to spot these helpful, colorful little insects in your garden is to move slowly and quietly, and observe carefully. Sometimes all I have to do is pause next to a group of flat-topped flowers (white or yellow ones seem to be their favorites), and within a few minutes one or two will show up to eat (and to dazzle me—in morning sunlight these exceptional little pollinators shimmer!). I’ve photographed nine different species in my small yard, and I’ve just started. Hopefully I’ll encounter many more of these fascinating little flyers in the years to come.

To avoid confusion with bees and wasps, just remember that syrphid flies have huge compound eyes (which help to determine their gender—female eyes are spaced slightly apart while males’ come together at the top of their head); their bodies are sometimes flatter than bees and wasps; their antennae are usually very short; they don’t carry pollen around like most bees do; they have one pair of wings (unlike bees and wasps that have two pairs). The second pair of wings of flies has been reduced to two little knobs called halteres, which can be seen in the photo below. Halteres function like tiny gyroscopes that allow them to stay balanced by detecting and correcting changes in rotation while flying, and enable their zippy acrobatic flights.

Although the mouth parts of syrphids vary between species, allowing different species to access nectar in differently shaped flowers, their typical mouth is basically a retractable extension with a spongelike tip that can soak up either nectar or pollen. The species that have this can only feed on open flowers that have easily accessible nectar. Some species have a modified mouth that allows them to feed at elongated, tubular flowers.

The halteres can be seen at the base of the wings.

The halteres can be seen at the base of the wings.

 

Conservation
Syrphid flies have been studied very little in the U.S., but European research has shown that species diversity has fallen in areas of intensive human activity. According to the Xerces Society, in Britain, seven of the 22 flies for which Biodiversity Action Plans have been prepared are syrphid flies. Given the substantial loss of pollinators induced by habitat loss, pesticides, nonnative species and climate chaos, and the profusion of others in danger of extinction, there is a definite need to conserve all types of wild pollinator communities.

Providing for these flies is similar to most other pollinators: A variety of flowers from spring till fall for adults, and appropriate habitat for egg laying, larval development, and overwintering. Attract and nurture syrphid flies with a diversity of native plants that provide a lot of nectar and pollen (females need pollen to produce eggs). In the Pacific Northwest, try yarrow (Achillea millefolium var. occidentalis), stonecrop (Sedum spp.), goldenrod (Solidago canadensis), blue-eyed grass (Sisyrinchium spp.), fleabane (Erigeron spp.), white spiraea (Spiraea betulifolia var. lucida), mock orange (Philadelphus lewisii), and aster (Symphiotrichum spp.). The flowers of chamomile, dill, parsley, and other garden herbs with flat-topped flowers are also very attractive to them, as is the pollen of grasses and sedges that’s often available early in the season. Be sure to allow leaf litter and downed wood to remain on soil to help them get through the winter and to provide food for the decomposer types.

Aphid remedy
If you have an aphid problem on some plants, remember that predatory insects that keep pests at acceptable levels need prey like aphids. Always inspect aphid colonies for syrphid fly larvae before even thinking about control, even “organic” remedies. Use only plain water to spray off aphids (that can’t climb back on), but only if necessary. Never, ever use insecticides, to which syrphid flies and other creatures are very sensitive. Usually, just turning your back is the best thing: One summer a large patch of native bleeding heart (Dicentra formosa) in my backyard was absolutely infested with aphids. I decided to let nature take her course—cheering on the ladybird beetles and birds who flourished with the situation. As the leaves died back (as they do naturally when the heat of summer arrives) I forgot about the aphids. The following year there were scarcely any on the bleeding heart, but I found another species of aphid on nodding onion (Allium cernuum); again I did nothing and nature took care of it. The following year the wild onion and bleeding heart were fine, but the aspen trees were stricken. Yet again, ladybugs, lacewings, and several species of songbirds took advantage of the generous buffet. The following year there were no outbreaks in my yard, at least none that I noticed.

 

Syrphus opinator (female) on Spiraea betulifolia var. lucida

Syrphus opinator (female) on white spiraea (Spiraea betulifolia var. lucida)

 

Eristatis male on yarrow (Achillea millefolium var. occidentalis

Eristalis sp. on yarrow (Achillea millefolium var. occidentalis)

 

© Eileen M. Stark 2016

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Beyond Bees: The Underappreciated Pollinators

Common ringlet (Coenonympha tulle)
The majority of flowering plants evolved to take advantage of insects, and depend on them (and less commonly, other animals or wind) to fertilize their flowers, facilitate gene flow, and prevent inbreeding. Bees might be the most obvious pollinators, and on a warm summer day it seems flowers and bees were made for each other. Native bees, including the 90% of species native to the U.S. that are solitary rather than social — that is, females create nests and raise their young without the help of any other bees — are considered to be the most important pollinators (move over, European honeybees!) and are invaluable members of natural systems. But other capable pollinators—like butterflies and moths, hummingbirds, wasps, ants, herbivorous fruit bats, and even rodents—share the pollen distribution workload, and offer ecological benefits as well. Less well known are the thrips, beetles, mosquitoes (yes, you read that right), and flies that are actually quite accomplished pollinators. Distributing pollen may be a sideline for them, but they often excel because they don’t take pollen back to their nests, as most bees do.

Thrips go way back—to the Permian period, over 250 million years ago—but get a bad rap because of a few species that threaten crops. Studies show that they are strong pollinators of some plants, particularly early in the season when most other pollinators aren’t around.

The adult ornate checkered beetle (Trichodes ornatus) feeds on flowers such as wild buckwheat (Eriogonum spp.), transferring pollen from anther to stigma.

The adult ornate checkered beetle (Trichomes oranatus) feeds on flowers such as wild buckwheat (Eriogonum sp.) and helps transfer pollen from anther to stigma.

Beetles are particularly important in semi-arid parts of the world and have a highly developed sense of smell. They are expert and essential pollinators, according to the Forest Service, and also were around millions of years before bees appeared. Like many species of birds, bees, and butterflies, beetles are in danger of extinction. The International Union for Conservation of Nature lists over 70 beetle species as endangered. The main threats include habitat destruction, chemical pollutants (e.g., pesticides), displacement by introduced species, and hybridization with other species due to human interference.

Although many flies (order Diptera) are recorded as flower visitors, relatively little is known about pollination by flies, compared to other more obvious pollinators. Many flies are strong pollinators, including syrphid flies (which deserve their very own special post) as well as some tachinid flies, which are the most diverse family of the order Diptera (true flies). As adults, they are flower visitors, feeding on nectar and/or pollen; in their larval stages many species help to control insects that we consider pests.

Suillia spp. attracted to bear grass (Xerophyllum tenax) receives a pollen reward.

Pollination by insects is usually mutually beneficial. Here, a fly (Suillia variegata) attracted to bear grass (Xerophyllum tenax) receives a pollen reward and the flower gets fertilized.

While I’m not advocating the nurture of mosquitoes in your garden (the females do suck blood and can carry disease, after all!), it’s noteworthy that mosquitoes, like all insects, do have a role in natural systems. Their primary source of food is flower nectar (with males eating nothing but nectar) and they buzzily and incidentally carry pollen from flower to flower. Plants like goldenrod (Solidago spp.) use mosquitoes as pollinators, as do orchids of northern latitudes, grasses, and many other types of plants. And they are a source of food for birds, fish, amphibians, spiders, bats, dragonfly larvae, and other animals.

How you can help a variety of pollinators

Within our increasingly fragmented landscapes, gardens that provide pollen and nectar-rich plants—as well as nesting and overwintering sites—can create critical habitat and connections for pollinators and other creatures. No space is too small, and when in close proximity to other larger gardens, natural areas, or greenways that sustain native plant populations appropriate to the region, their value deepens.

◊ Choose natives that occur naturally in your area, or at the very least heirloom ornamentals (rather than newer hybrids that may not provide sufficient or appropriate nutrients that native species do). Some garden herbs like cilantro, parsley, and dill attract some pollinators when allowed to flower.

◊ Avoid nonnative invasive species like “butterfly bush” (Buddleia davidii) that sound good, but aren’t.

◊ Provide structure and layering in the form of native trees and shrubs that provide food, cover and nesting sites for various pollinators.

Syrphid _ Eumerus sp.

Syrphid fly (Eumerus sp.) on Sedum spathulifolium, a west coast native.

◊ Plan for continuous flowering, spring through fall. Early spring nectar is particularly important for early-emerging queen bumble bees and other solitary bees, as well as flies and beetles.

◊ Choose a variety of plants that differ in the size, shape, and color of blossoms to attract a variety of pollinators. Arrange perennials in drifts or swaths of at least three of a kind, rather than singly here and there. And don’t forget that trees and shrubs produce flowers!

◊ Stay away from pesticides and other chemicals. Insecticides, herbicides, fungicides, and synthetic fertilizers are particularly harmful to sensitive pollinators. Don’t purchase plants pre-treated with neonicotinoids; if you’re unsure, ask.

◊ Don’t be too neat. Leaf litter, dead wood (tree snags or piles of branches), and other natural detritus provide essential habitat, nesting materials, and overwintering sites for adult pollinators or their eggs, larvae, or pupae. And allow some bare soil for pollinators that nest in the ground.

◊ Grow lepidoptera (butterfly and moth) host plants that provide food and habitat for their young. Find out which species frequent your area and grow the native plants that they need to breed.

◊ Provide shallow water and some moist soil. A shallow pie plate or flowerpot saucer, filled with clean gravel or small rocks allow insects to drink without drowning. Also, butterflies and moths need muddy or sandy puddles to obtain water and nutrients. Add a dash of salt to be sure male Lepidoptera get enough sodium prior to mating.

Please see this post for more detailed info on supporting pollinators in all their life stages.

© Eileen M. Stark 2016

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Attract Ladybird Beetles (“Ladybugs”) to Your Northwest Garden Humanely

_MG_2279

The Western blood-red ladybird beetle (Cycloneda polita) — one of about 90 species throughout the Pacific Northwest and about 6,000 species worldwide — is tiny (4 to 5 mm), but like most others in the Coccinellidae family, is a voracious consumer of aphids, scale insects, and mites; a few species eat fungi. Revered for centuries due to their role as a pest controller, ladybird beetles at one time were even thought to have supernatural powers. The “lady” for whom they were named was the “Virgin Mary.” Once you have these native predators in your garden you’ll want to keep them, and there’s an easy way to do that.

But first, a little about these endearing little insects, the vast majority of which are beneficial: The most obvious ladybird beetles (often called “ladybugs” in North America, although they are not true bugs) evolved a brightly colored shell to exhibit what biologists call aposematic (warning) coloration, which functions to repel and warn predators that they taste awful (due to production of toxic and unpalatable alkaloids). The “eyespots” on their pronotum (that covers the thorax) are a form of mimicry, possibly to further fool a predator by appearing dangerous, or by adding to the inedibility factor. Their actual face is the tiny black and white portion with brown antennae that you can see in the photo above. The Western blood-red ladybird beetle is plain and without spots, but some species have remarkable color patterns that vary greatly and make identification difficult. Other species lack dramatic coloration.

Life Cycle
Adults are commonly seen on plants in spring and summer, foraging for small invertebrate prey (often aphids), although they will eat nectar, water, or honeydew (the sugary secretion from insects like aphids and white flies) when food is scarce. They overwinter by hibernating in large clusters, often spending the winter under leaf litter, rocks, downed wood, or other debris. If they get into your house in autumn as temperatures plummet, please don’t kill them. Since they need cool temperatures and moisture during the winter (which our homes lack), gently place them back outside under fallen leaves. In hard to reach places (like ceilings) I suggest fastening a piece of lightweight fabric (perhaps a lightweight sock or piece of nylon stocking) onto the end of a vacuum cleaner hose with a rubber band, so that an inch or two of fabric protrudes into the hose. Then, with the power turned down as low as possible, quickly suck them into the fabric, gently remove the fabric with the beetles, and release them under a pile of leaves outdoors. To help prevent future interlopers, caulk cracks and crevices around doors and windows and repair any damaged siding that’s allowing them to get in.

Ladybird beetle larvae are long and flat and are usually covered with little spines, spots and stripes, and resemble tiny alligators. Though sometimes erroneously mistaken for pests, they are completely harmless to humans. Usually found in or near aphid colonies, they feed voraciously on insects for several weeks, then pupate on leaves. Some species produce several generations per year, while others have only one. During the summer, all stages may be seen.

How to Acquire
The best way to get these hungry predators into your garden is not to purchase them, but to provide native habitat and not use any insecticides. The food that they need comes from native plants that naturally attract insect herbivores. In my yard I notice Cycloneda polita (pictured) feeding on lupine (Lupinus spp.), western bleeding heart (Dicentra formosa), fleabane (Erigeron spp.), honeysuckle vines (Lonicera ciliosa and L. hispidula), and this year for the first time, aspen trees (which are also attracting birds like bushtits and kinglets who love to eat aphids).Western blood-red ladybird beetle

Don’t buy them
In the early 1900’s, literally tons of Asian beetles were collected and shipped to agricultural fields. Tragically, over half died during shipments and most of the rest quickly dispersed before the wretched experiment finally ended. Today, ladybird beetles are again popular, but beware the ramifications. According to Judy and Peter Haggard, authors of “Insects of the Pacific Northwest” (Timber Press, 2006), the commercial exploitation of ladybird beetles involves collecting them while they are hibernating, which can be devastating to their populations. “Those innocent-looking mesh bags … in the local garden shop actually represent a cruel and unconscionable practice: Ladybird beetles sold in retail stores are usually exposed to high temperatures, low humidity, and no food for weeks. Even if they survive until bought and released, they are often so weakened, they die soon after being released.” And the ones who do survive usually quickly disperse to areas other than your yard. Bottom line: Don’t purchase them.

To add to the destruction, beetles sold commercially are usually not native species and, as such, are a serious threat to native insect species, including native lady beetles. According to the Oregon Department of Agriculture, “Even species native to North America but collected outside of Oregon should not be released because they may carry diseases and parasites not found in Oregon.”

 

© Eileen M. Stark 2016

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Fragrance in a Northwest Garden: Western mock orange (Philadelphus lewisii)

Philadelphus lewisii

Had Carl Sandburg penned a poem about the way a captivating scent wafts through the air — prior to his famous “Fog” — he might have written that it approaches us “on little cat feet.” Like fog, scent is silent and invisible and adds a fresh, sensual dimension to a garden (or a walk in the woods for that matter). One of the most fragrant flowering shrubs is mock orange, and the Pacific Northwest’s native offering, Philadelphus lewisii (Western mock orange or Lewis’ mock orange), doesn’t disappoint. Plan ahead and place this medium-sized deciduous shrub where its fragrance can be noticed.

Philadelphus lewisii is named after scientist and explorer Meriwether Lewis, who collected it in 1806 during the Lewis and Clark expedition. Native Americans had numerous uses for it, including making tools, snowshoes, furniture, and even soap.

How it grows
Although there is quite a bit of individual variation within this species, the structure and growth pattern of this particular shrub goes something like this: Maturing at 5 to 12 feet tall and nearly as wide, this fairly fast grower may send out arching basal shoots as it ages, and eventually become a thicket. In late spring, flowering shoots appear, followed by vegetative growth. Rich green, egg-shaped leaves (roughly three inches long) grow in pairs along its stems. At the tips of branches, multiple clusters of white, four-petalled blossoms adorned with soft yellow stamens emerge in late spring or early summer and sparkle against a green, leafy backdrop. Flowers measure one to two inches in diameter, and offer a lovely, fruity fragrance.

Wildlife value
Mock orange’s fragrance doesn’t just appeal to us, though—it attracts nocturnal moths and butterflies like the western tiger swallowtail. As they feed on its nectar and incidentally brush against theSyrphid fly on Philadelphus lewisii flower’s anthers, thousands of male pollen particles are released, pollinating its flowers. Other pollinators attracted to scent include bees, but also syrphid flies (aka flower flies), which are particularly fond of white and yellow flowers. In late summer into winter, mock orange’s wildlife appeal continues as the plant’s tiny seeds are consumed by many species of birds, including goldfinches, as well as squirrels. It also provides twiggy cover year round.

Try it at home
Mock orange is easy to grow. It tolerates both drought (after it’s established, of course) and moisture, and will do well in full to part sun or in a fair amount of shade (but not deep, dark shade). It’s also a good shrub for stabilizing soil on slopes due to a fibrous root system. While it’s not fussy about soil, if your soil’s in bad shape consider incorporating and/or mulching with some decomposed organic matter (like compost) to get it off to a good start.

It’s best to let native plants attain their natural size and habit, but if yours was placed too close to a path or some such, pruning may be necessary. Mock orange should only be pruned soon after flowering since next year’s blossoms develop on the previous year’s growth.

Philadelphus lewisii

 

Grab a partner
Though not common, western mock orange is widespread. It occurs naturally from southern B.C. to northern California and the Sierras, and east to Alberta and western Montana, at low to mid-elevations. Growing along creeks and seeps and forest edges, on hillsides, and within chaparral and pine and fir communities, it associates with species such as Douglas-fir, oceanspray, ninebark, osoberry, baldhip rose, tall Oregon grape, and others. If space allows, try it as a member of a multi-species (unclipped) hedgerow (should pruning be necessary, do it soon after flowering, so that the following year’s blossoms aren’t affected). To stimulate flowering on older shrubs, cut back flowered growth to strong young shoots, cutting out up to 20 percent of aging stems near their base.

Other fragrant PNW plants include wallflower (Erysimum capitatum), Nootka rose (Rosa nutkana), clustered rose (Rosa pisocarpa), bald hip rose (Rosa gymnocarpa), Oregon grape (Mahonia spp.), fringecup (Tellima grandiflora), serviceberry (Amelanchier alnifolia), checker mallow (Sidalcea spp.), oceanspray (Holodiscus discolor), some ceanothus (Ceanothus spp.), bear grass (Xerophyllum tenax), milkweed (Asclepias spp.), madrone (Arbutus menziesii), and black hawthorn (Crataegus douglasii). Enjoy!

 

© 2016 Eileen M. Stark

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What Makes Leaves Change Color?

Populus tremuloides (quaking aspen)

I’ve written quite a bit about the importance of leaf “litter” on the ground, so here’s a little info on how it gets there and what conditions make for the most vibrant leaves. While it’s understandable to think that it is the cooler temperatures of the fall season that bring about color change, there are several other factors. Besides temperature, sunlight and soil moisture influence the quality of autumn leaf color. But the process that instigates the show is actually more of a chemical process brought on by less daylight.

Darkness rules

Most plants are quite sensitive to each day’s length of darkness. In early fall, when nights begin to lengthen, the cells near the joint of the leaf and stem in deciduous trees and shrubs are triggered to divide quickly. This corky layer of cells (the abscission zone) begin to block transport of essentials such as carbohydrates from the leaf to the branch, as well as the flow of minerals from roots upward to leaves.

When plants are actively growing, green chlorophyll is constantly produced in the leaves. But in autumn, when the connection between the leaf and the rest of the plant gets more and more obstructed, chlorophyll replacement slows and then stops completely. This is when autumn colors are revealed: Normally masked by chlorophyll, yellow pigments called xanthophylls and orange pigments known as carotenoids become visible when chlorophyll shuts down. Red and purple pigments come from anthocyanins which are created (in some species) from sugars within the leaf and it’s speculated that they are a defense mechanism that helps some plants fight herbivores like aphids.

Spiraea betulifolia var. lucidaAs fall moves forward, the cells in the abscission layer become drier and weaker and leaves eventually part company with the plant. Many trees and shrubs lose their leaves when they are still colorful (making for some gorgeous mulch!), while some retain the majority of their foliage through much of winter, though their leaves lose color fairly quickly. Like chlorophyll, the other pigments eventually break down in light or when frozen. The final pigments are tannins, which look brown. An example is the Oregon white oak (or Garry oak), which appears golden for just a few days before turning brown.

Recipe for color

Low temps (but above freezing) and ample sunlight following formation of the abscission layer cause quick destruction of chlorophyll and promote the formation of bright colors in some species. Stress from drought during the growing season can sometimes trigger early formation of the abscission layer, resulting in leaf drop before they have a chance to develop fall coloration, so a growing season with ample moisture that is followed by somewhat dry, warm, sunny, calm fall days with cool, frost-free nights provides the best recipe for bright fall colors.

Plant natives!

Besides offering the most ecological benefits, some native species grown in their native ground offer wonderful fall color that rivals that of nonnative plants. Here in the Pacific Northwest, some of the most vibrantly colored leaves occur on natives such as paper birch, black hawthorn, Oregon ash, quaking aspen (pictured, top), golden currant, vine maple, serviceberry, and red-twig dogwood. Enjoy!

 

© 2015 Eileen M. Stark

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Best Early Spring-Flowering Shrubs for Pacific Northwest Pollinators

Ribes sanguineum

Plan ahead for hungry native pollinators who need early-flowering plants like red-flowering currant to survive.

 

April showers may bring May flowers, but what about providing forage for hungry pollinators that need food earlier in the year? To provide large amounts of nectar and pollen in late winter and early spring for emerging bees as well as hummingbirds and other pollinators, to help you endure the gray winter skies and store carbon, and to get the most bang from your buck, add early-flowering native shrubs to your garden. Get new shrubs in the ground preferably in autumn—so the plants benefit from winter rains, and to ensure that you have the early part of a continuous succession of flowers covered.

Here are five early-flowering shrubs (plus one shrubby tree that’s pollinated by wind), listed in order of size from largest to smallest, that naturally occur in large areas of the Pacific Northwest region west of the Cascades. They grow in sun to partial shade, are fairly easy to find at native plant nurseries (as well as nurseries that don’t focus on natives), and are quite easy to grow, provided they are kept adequately moist until they are established (2 to 5 years). All would do well planted in wide, unpruned hedgerows. When choosing any shrub, note its eventual width to be sure you have enough space for it to stretch its limbs and attain its natural form at maturity—and to eliminate future hack jobs by a pruner. 

Buy plants that are responsibly propagated from source material that originated as close as possible to your site. Using such “local genotypes” helps ensure that you get plants that are well adapted to your area and that genetic diversity—which helps plants (and animals) adapt to changing conditions—is preserved. Ask growers and nurseries about their sources.

Salix scoulerianaScouler’s willow (Salix scouleriana): A fast-growing deciduous shrub or small tree. Flowers are soft catkins, larger than horticultural “pussy willows,” and appear in early to mid-spring. Male and female flowers are on different plants, so grow both for seeds. Scouler willow is a larval host plant for several butterfly species. Does not tolerate full shade. Prefers moist soil. 20-30 feet tall by 10-15 feet wide at maturity. 

 

Oemleria cerasiformis

 

Osoberry (Oemleria cerasiformis): A large, arching deciduous shrub or small tree that blooms prolifically in late winter as leaves emerge. Tolerates clay soil well, but does best with some shade (nature places it in the dappled shade of tall trees). Plants are either male or female, so plant several to produce the fruit that birds need. 12-18 feet by 10-14 feet at maturity.

Amelanchier alnifolia

 

 

Serviceberry (Amelanchier alnifolia): A versatile, multibranched shrub with lovely white, fragrant flowers in mid to late spring. Bluish-green leaves turn gold to reddish in autumn. Larval host plant for several butterfly species. Needs well-drained soil with adequate organic matter. Tolerates full sun in cool areas. Doesn’t like competition, so plant other shrubs and perennials at least several feet away. 8-18 feet tall by 6-10 feet wide at maturity.


Red-flowering currant (Ribes sanguineum): An upright, deciduous shrub with nearly year-round appeal. Gorgeous, pendulous, lightly fragrant flower clusters (pictured, top) that bloom in early spring are followed by powder-blue berries. Leaves turn golden in late autumn. Larval host plant for butterfly larvae. Controls erosion. Can’t handle excessively wet soils, so be sure soil drains well and plant it away from rain gardens and other drainage areas.  7-10 feet tall by 6-9 feet wide at maturity. More info in this post. 


Mahonia aquifoliumTall Oregon grape (Mahonia aquifolium): A handsome, multitalented evergreen shrub with an upright growth habit. Bursts into flower brilliantly in early to mid-spring, for a long period. Tolerates acidic soils. Has somewhat prickly evergreen leaves, so site it where it won’t be brushed against frequently. 5-9 feet tall by 3-6 feet wide. Will spread slowly. More info in this post.

 

The earliest winter bloomer is the handsome beaked hazelnut (Corylus cornuta var. californica), a beautifully textured, large multistemmed woodland shrub or small tree that grows to 10-20 feet tall by 10-20 feet wide. It is pollinated by wind, not animals. More info here.

After planting
Add a few inches of organic matter as mulch around the shrub (but keep away from trunk) to insulate, keep weeds down, and add nutrients. Fallen leaves work well, as does weed-free compost. If you use wood chips, make sure they aren’t finely ground and/or fresh, and don’t dig them into soil—under-composted chips and bark can deplete soil of nitrogen during breakdown. Later on, simply allow fallen leaves to remain on soil to provide habitat and nutrients.

All of these shrubs are drought tolerant when established (although Scouler willow does best with supplemental summer water), but they will appreciate some irrigation in very hot situations. They should need little to no pruning if they’ve been sited to allow room for their growth.

If you already grow any of these shrubs, I’d love to hear what wild species you’ve seen attracted to them. Or how much they brighten your garden on drab winter days?


© 2015 Eileen M. Stark

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Autumn Leaves Benefit Your Garden in Countless Ways

 

leaves

 

Leaves offer great benefits to wildlife and your garden’s soil. Don’t throw them away!

In another post I extol the virtues of letting leaves do their thing. By that I mean allowing them to do what nature intended: Protect and enrich the soil, offer food for ground-feeding birds, provide a nursery for butterfly larvae/pupae and cover for overwintering queen bumblebees and other beneficial insects and microbes, afford animals like frogs and salamanders places to hunt and Varied thrush foraginghide, and myriad other ingenious things. Leaf litter breaks down with the help of mycorrhizal fungi that move carbon into soil, extract nutrients for plants and protect them from disease, lessen soil erosion, and play a very important role in storing the gigantic pool of carbon within soil.

I’m not sure how leaves got such a bad reputation—I constantly see and hear people blowing them and raking them not only from hardscape and lawn (which is understandable), but also from bare soil. I’m not sure what the aversion is, unless it’s another kind of “biophobia,” in this case a fear of organic materials. Another no-no is putting leaves in the trash, which ends up in landfills. The US EPA says that nationwide, 13 percent, or about 33 million tons of municipal solid waste is from leaves and grass and tree/shrub trimmings. Here in Portland, as well as some other cities, there is curbside pickup for green waste for those who don’t compost, and the city picks up leaves from the streets of leafy neighborhoods every autumn to make leaf compost that residents can purchase for a modest fee. But using them in your yard is much better because it improves the soil, helps prevent erosion, and helps maintain populations of pollinators such as butterflies and bees, and other insects, as well as microscopic organisms!

How to do it: For areas like driveways, walks, sewer grates and drainage pathways, rake them up (but please don’t use noisy, polluting leaf blowers), and use them as follows:

Mulch your beds.Take raked leaves from hardscape and lawn and place them in your planted beds, a couple of inches thick to protect the soil and provide insulation from the cold (if you live in a very cold climate, add more). Keep them off of tree and shrub trunks and perennial crowns to prevent rot. Try to do your raking on a non-windy day and consider moistening them after you apply them if it’s a dry day. Don’t shred leaves before applying—it won’t help the wildlife described above.

If you must have lawn, leave small amounts of leaves on it and mulch them in situ. Use your mower to shred leaves on grass to improve lawn health by naturally fertilizing the soil. Freshly fallen leaves are high in minerals, and don’t kill soil organisms like synthetic fertilizers do.

Make leaf compost. Leaves collected from hardscape and such can be composted separately to make leaf compost (also known as leaf mold), a great soil conditioner. If you have a lot of space, simply round them up into large piles and let nature break them down with fungus and microscopic creatures. If space is lacking or you want more control, create round chicken wire enclosures or wooden compost bins and fill them with leaves. You can also dig large depressions and fill them with Homemade compostleaves. Keep piles moist (but not completely saturated). During excessively rainy periods, consider covering the pile if possible. In a year or more (depending on the type of leaves used), after the leaves have broken down, you will have some very dark, crumbly humus to add to your veggie beds and other places that need high quality soil (but as mentioned below, remember that covering bare soil with any mulch can kill ground-nesting bees, so be sure to check the soil before applying).

Add leaves to your mixed compost bins, heaps, or cages. In your mixed compost bin, add collected leaves—which are mostly carbon—to help balance the “greens” (compost should be roughly half “greens” and half “browns”). Consider storing extra leaves and adding them to your compost bin throughout future months.

Save some for spring. If you have a large amount of leaves, put some aside—or just take some from your leaf compost heap—to use as mulch next year. Mulch applied in spring, after the soil warms, helps maintain soil moisture and protects the soil from oxidation. Be sure to leave some soil bare though, because the majority of native bees nest in the ground and cannot get through thick layers of mulch.

One word of caution: Leaf compost generally makes the soil slightly more acidic. This won’t be a problem for most Pacific Northwest native species, which evolved in slightly acidic soil. But when using leaf compost in vegetable beds, test your soil’s pH — it may need a bit of lime to keep the soil neutral or slightly alkaline, which many cultivated vegetable plants need.

 
Wonder how much life is trucked away in these leaves …

© 2015 Eileen M. Stark

Posted on by Eileen Stark

New Study: Non-native Plants Reduce Insect Diversity

Acer circinatum (vine maple)

Natives like vine maple (Acer circinatum), surpass nonnatives for restoring biodiversity


As if we need further proof, a new study published recently in Ecology Letters demonstrates that native plants are much better at supporting local insects than nonnative species, and that nonnative plants are exacerbating biodiversity loss with their inability to support many insect herbivores.

The researchers planted test gardens with both native and nonnative tree species and collected data over a three-year period. They measured the insect herbivore species and communities that were using the plants, and compared native trees to nonnative trees of two types: Those with close native relatives in the region and those that had no close native relatives.

They found that nonnative trees with a native relative (in the PNW, think nonnative scarlet oak, which is related to the native Garry oak) host and support fewer species of insects than the native counterpart, and that few of them were unique to that species of tree. The result was even more striking with nonnative trees that had no native relative in the region (such as golden chain tree, a European species).

The study also found that young insects, which are most supportive of an ecosystem, were found on the native trees. Adult insects, on the other hand, may be found on plants, but for various reasons—to rest, to warm themselves, breed, etc.

Essentially, when the diversity of insect herbivores—which are the basis of the food web—plummet, so too do all the species that rely on them for food. If you’re not particularly fond of insects, think of them as baby food: In spring and early summer, when insect eggs are hatching and larvae are feeding, most birds are wholly dependent on insects to feed to their young, as well as to keep their own strength up. And most other wild species rely on insect herbivores in one way or another. Even predators like bobcats need native plants, since they feed on wildlife that need insects and/or native plants to survive. 

So, this is more evidence that natives are the answer for restoring biodiversity, while most nonnatives are problematic. When selecting plant material—even in an urban area—choose plants that help the environment and its community members. Go for the native oaks, pines, maples, willows, etc., with their plethora of insects. There’s almost always a native option!

 

© 2015 Eileen M. Stark

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Northwest Native Pollinator Plants for Late Summer to Fall

Late season pollinator plants

Scientists know that bees are dying for a variety of reasons—pesticides, habitat destruction, drought, climate change, nutrition deficit, air pollution, and so on, which makes us the obvious perpetrator. We can help give back to them (and other pollinators) by growing flowering native plants in our gardens (as well as noninvasive exotics that step in when a native plant isn’t available or feasible), with consecutive blooms from early spring till fall. To provide for many different types of pollinators—from long and short-tongued bumblebees to syrphid flies, hummingbirds, and beetles—offer a variety of flower shapes, colors, and sizes, with smaller plants in groups of at least three of the same species (like a big, obvious “Eat Here” sign). Fragrance is also important for attracting insects to flowers and guiding them to food within the flower, and aiding an insect’s ability to efficiently learn particular food sources.

Below are some native perennials and one shrub that offer food for pollinators from mid or late summer to fall in the Pacific Northwest, west of the Cascades. There are more candidates, but I chose these species because they naturally occur in fairly large parts of the region, are generally easy to grow, and are not too hard to find at nurseries (although you will likely have to call around for availability). I’ve listed them alphabetically with some very basic care guidelines. It’s best to plant them in the fall, just before or as the rain returns.

As always, plan ahead and choose species that fit your light, moisture, and soil conditions, but also choose those that are appropriate to the natural landscape—that is, look to nearby natural areas, and add flora that would likely have grown in your area historically, if possible. You can also check a species’ natural range (to county level) here, or check with your local native plant society chapter or county soil and water conservation district. No fertilizer is necessary and please don’t use any pesticides. Keep them adequately hydrated—by watering deeply and infrequently to promote deep roots—until they’re established (2 to 5 years). Enjoy!

◊ Achillea millefolium var. occidentalis (Yarrow): Perennial. 1-3 feet tall x 1-3 feet wide. Sun to part sun. Not fussy about soil; moist or dry. Spreads by rhizomes or seed. Flat-topped clusters of white, fragrant flowers (pictured below) bloom through late summer. (Not to be confused with the Eurasian Achillea millefolium var. millefolium). Achillea millefolium var. occidentalis

◊ Anaphalis margaritacea (Pearly everlasting): Perennial. 1-3 feet tall x 1-2 feet wide. Sun to part shade. Likes moist soil with good drainage, but can tolerate drought once established. Pure white flowers are often used in dried flower arrangements. Besides providing nectar, it is a host plant for painted lady and skipper butterflies.

◊ Baccharis pilularis (Coyotebush): Evergreen or semi-evergreen shrub. 5-8 feet tall x 6-8 feet wide. Sun to part shade. Tolerates poor soils (but needs good drainage) and is drought tolerant. Flowers aren’t showy and are borne on separate male and female plants (male flowers creamy white; female pale green). Excellent wildlife habitat plant but is deer resistant.

048_Campanula rotundiflora sRGB◊ Campanula rotundifolia (common harebell): Perennial. 1-2 feet tall x 1-2 feet wide. Sun to part shade. Moist to dry, well-drained soil, preferably with a good amount of organic matter. Spreads slowly by rhizomes or seed. Bell-shaped, bluish violet flowers typically bloom through late summer. (pictured left)

◊ Gaillardia aristata (blanketflower): Perennial (short-lived). 1-3 feet tall x 1-3 feet wide. Sun to light shade. Tolerates a variety of well-drained soils; drought tolerant when established. Spreads by seed. Colorful yellow and reddish orange flowers bloom well into fall, especially when dead-headed. Deer resistant.

◊ Solidago canadensis (Goldenrod): Perennial. 2-4 feet tall x 2-3 feet wide. Sun to part shade. Solidago canadensisTolerates wide range of soils; prefers moisture but tolerates drought when established. Spreads by rhizomes or seed. Bright gold, fragrant inflorescences typically bloom well into fall. (pictured right)

◊ Symphyotrichum subspicatum (Douglas aster): Perennial. 2-3 feet tall x 2-3 feet wide. Sun to part shade. Does best in moist soil that is rich in organic matter. Spreads slowly by rhizomes and seed. Lavender-blue daisylike flowers bloom from mid summer until mid fall. (pictured below)

 

 

Douglas aster

 

 

© 2015 Eileen M. Stark

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Drought’s No Fun for Wildlife, Either

Bushtits at gradually sloping birdbath

Here in the Pacific Northwest (as well as the interior Northwest, northern Rockies and northern California) we’re experiencing a hot and early summer. Nearly everything’s been premature—most trees leafed out several weeks before they typically do and herbaceous plants popped up ahead of time; those that flower were more than punctual. My raspberries and thimbleberries were three weeks early, and I’m picking apples now that usually ripen several weeks from now. Portland set a record for a dry June and will likely break another this week for the highest number of consecutive days over 90˚.

The winter was pleasantly mild and precipitation was paltry: Snowpack in Oregon was 11% of normal and Washington’s was 16%. If the current drought and dry heat makes us thirsty, we’re not alone. Nearly all of life’s processes require water in one form or another—it’s essential for everything from small insects to birds to bobcats. Of course, areas further south are much more drought stricken, with wildlife emaciated and dehydrated. Some say it will only worsen, due to climate change.IMG_6764

Drought causes many deadly, far-reaching effects for wildlife, including less food and cover, increased vulnerability to predators and diseases, competition with others of their kind, and more conflicts with people as they desperately search for food and water outside their normal range. Although some animals obtain moisture from their prey, they still depend on water in the environment to provide for those they need to eat. Tiny creatures may find enough in dew droplets, but many species require additional water to survive. Birds, for example, need water to drink of course, but also to bathe in to help keep their feathers clean and waterproof—essential for insulation and flight.

Dehydration is dangerous for everyone. If you want to help wild visitors in your yard, below are some quick, easy options. Artificial ponds can be a wonderful addition to larger gardens, but they aren’t quick and easy, so they’re not included here.

Scrub jay takes a drinkBirdbaths: Birdbaths that slope gradually are best because all sizes of visitors can wade in to a safe and comfortable depth. If you already have one that has steep sides, place some flat rocks on one side to create a shallow area. Site birdbaths in open areas, at least 10 feet from any hiding places were domesticated predators could lurk. Use hanging birdbaths whenever possible if predation is a problem in your yard. And keep them as clean as possible: Replace the water every day or two (this will also keep mosquitoes from breeding) and give them a good scrubbing every few weeks, but don’t use bleach.

Mud puddles: Most butterflies and moths (Lepidoptera), as well as some types of insects and birds, require moist soil or sand to obtain essential nutrients. Lepidoptera, for example, “sip” earthy cocktails that contain minerals such as salts which are essential for reproduction. Just the other day I saw a Western tiger swallowtail pressing his proboscis into the recently irrigated soil in a community garden plot. Male Lepidoptera give their significant others an extra little gift of minerals while mating which ensures that the largest number of eggs develop. In nature, this “mud puddling,” as it is called, is done at the edges of streams and other moist places. You can mimic this habitat by filling a large ceramic bowl with sand and burying it part way in your garden. Mix in some salt for males and place some round rocks (for landing and basking) around the edges. And don’t be too quick to pick up moist fallen fruit (like figs, should you have them)—some Lepidoptera species can’t resist such fermenting treats. More on feeding butterflies in a future post!

Moist gravel for bugsPlates of moist gravel: Beneficial insects and other small arthropods will sometimes come to shallow birdbaths, but ground dwellers—like beetles—will appreciate a plate or pie pan filled with clean pebbles or gravel and water, and placed on the ground out of hot sunlight. Just be sure the water doesn’t rise above the gravel so that no one drowns.

It looks like we may be in for a very hot summer throughout most of the Northwest. Providing water in your garden will attract wild visitors and maybe even save lives.

 

© 2015 Eileen M. Stark

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Attract Butterflies with Northwest Native Plants and More

Red admiral butterfly

It’s so delightful when a lovely butterfly (is there any other kind?) floats into our yard. Each year, as soon as June rolls around, I catch glimpses of gorgeous Western tiger swallowtails and orangey Painted ladies flitting here and there, as well as the occasional Mourning Cloak in the vicinity of our octogenarian American elm tree, one of its host plants. This summer I’ve noticed, for the first time, a Red Admiral butterfly (Vanessa atalanta) gliding in now and then. This species is reportedly rather territorial and will stay in one area for days or even weeks, so I hope to see her again. She’s apparently attracted to the heat radiating from the rocks on the west-facing side of our veggie garden, as well as the white trellis that supports our cucumber plants, and this morning she surprised me by landing on the white shirt I was wearing. She was near some native wallflower (Erysimum capitatum) plants growing nearby, but I’m not certain she used them.

Red admirals aren’t very fussy about habitat, but for food they prefer sap from trees, fermented fruit, and bird droppings—yes, you read that right—from which they obtain nutrients, such as amino acids and salts that are necessary physiologically, behaviorally, and ecologically. Many butterfly species and some other insects consume droppings as well, and don’t get me started on the fascinating spider that masquerades as bird poop to hide from predators. Flower nectar is actually a second choice for red admirals, who only forage at flowers—such as aster, milkweed, penstemon, fireweed and wallflower—when sap, fruit, and droppings aren’t available.

Beyond food

But as you may know, butterflies need much more than food to survive and reproduce; they need to be protected during winter and also need “host” plants on which they can lay their eggs. These can’t be just any old plants; they need to be the kind that their larvae can feed on (as their ancestors have done for millennia) as they grow into pupa (chrysalis), that awkward metamorphic stage before adulthood. Some butterflies aren’t terribly picky and may be able to lay their eggs on four or five different plant species, but others, like monarchs and red admirals, can use only one species.

My butterfly reference tells me that red admirals lay their eggs only on plants of the nettle family (Urtica spp.), something I’ve never grown. Uh-oh. As I began pondering where the heck in my yard I could grow it, I suddenly remembered a wonderful nettle soup that I had at an equally wonderful villa on the west coast of Sweden some years back. It’s not only edible; it’s one of those “super foods” that are extremely rich in nutrients and purportedly very cleansing.

So now I’m on a mission to grow some native stinging nettle (Urtica dioica)—maybe a bit for us to eat, but mostly for the butterflies. It turns out that the Satyr comma butterfly also uses only nettle as a host plant, although they are reportedly rather rare in parts of their range and it’s highly unlikely I’ll ever see one in my urban yard. I prefer to grow it myself, so that the wild stuff in wilder places can be left to the butterflies. But first I’ll have to carefully figure out where to plant it … and buy some stinger-proof gloves. Or maybe I should just stick with providing for species that don’t need such outrageously prickly plants.

© 2015 Eileen M. Stark

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10 Great Northwest Native Pollinator Plants for Summer

Bombus vosnesenskii

In honor of National Pollinator Week, let’s zoom in on the bees and other hard-working pollinators whose lives are dictated by weather, season, and the availability of food, nesting habitat, and overwintering sites.

Nature has provided pollinators with unique ways of gathering nutritious pollen and nectar for their young, and they’re enthralling to watch. But bees and other pollinators are in terrible trouble worldwide due to our presence and actions. We can give back to them by growing flowering native plants in our gardens (as well as noninvasive exotics that are especially attractive to bees, like lavender and sunflower) with consecutive blooms from early spring till fall. But don’t forget to provide for them during all their life stages — not just their adult stage — by leaving the leaves, dead wood, and spent flower stalks to make sure they can get through the winter and have habitat to raise their young. And, no pesticides whatsoever!

If you’ve already included some native plants in your yard, you’re well on your way to providing for a wide variety of wildlife. Offering a variety of flower shapes, colors, and sizes, with smaller plants in groups of at least three of the same species (like a big, obvious “Eat” sign) will help provide for many different types of pollinators—from long and short-tongued bumblebees and syrphid flies to hummingbirds, beetles and thrips. Below are some Pacific Northwest native herbaceous perennials and shrubs that offer food for pollinators from early to mid or late summer in the Pacific Northwest, west of the Cascades.

The list is just a sampling (read about others in my book or within my blog’s PNW native plant profiles), and the species were chosen because they naturally occur in large parts of the region, are generally easy to grow, aren’t too hard to find at native plant nurseries (although you may need to call around for availability), and attract their fair share of native pollinators. I’ve listed them alphabetically with some basic care guidelines. Fall planting is best, as winter rains begin. (If you’re reading this in springtime, don’t worry—you can plant now, but you’ll definitely need to keep an eye on their water needs during the first couple of summers, at the very least.)

As always, plan ahead and choose plants that fit your light, moisture, and soil conditions, but also choose those that are appropriate to the natural landscape—that is, look to nearby natural areas and add flora that likely would have grown in your area historically. You can also search for a species’ natural range (to county level) here, or check with your local native plant society chapter or county soil & water conservation district. Growing them with associated species that evolved alongside them in nature will help them thrive. No fertilizer is necessary (although a one-time addition of compost such as leaf compost to the soil will add some nutrients and improve soil structure), but do keep them adequately hydrated until they’re established (2 to 5 years). Enjoy!

◊ Achillea millefollium var. occidentals (Western yarrow): Perennial. 1-3 feet tall x 1-3 feet wide. Sun to part sun. Not fussy about soil; moist or dry (will spread faster with more moisture). Spreads by rhizomes and seed. Flat-topped clusters of white, fragrant flowers bloom nearly all summer. (Not to be confused with the Eurasian Achillea millefolium var. millefolium).

◊ Asclepias speciosa or A. fascicularis or A. cordifolia (milkweed) : Perennial. 2-3 feet tall x 2-3 feet wide. Sun to part shade. Moist, well-drained soil, but can handle some drought when established. Rounded clusters of soft pink, fragrant flowers. Check out the Xerces Society’s info on milkweed of Oregon and of Washington. (A. fascicularis is pictured, right)Asclepias fascicularis

◊ Campanula rotundifolia (common harebell): Perennial. 1-2 feet tall x 1-2 feet wide. Sun to part sun. Well-drained, moist to dryish soil. Spreads slowly by rhizomes or seed. Bell shaped, violet-blue blossoms.

◊ Ceanothus velutinus (snowbrush): Fast growing evergreen shrub. 6-12 feet tall x 6-12 feet wide. Sun to part shade (intolerant of full shade). Rich or poor soil; very drought tolerant. Dense pyramidal clusters of tiny, fragrant white flowers. Occurs mainly at mid to high elevations; check natural occurrence, to county level, here.

◊ Erigeron speciosus (showy fleabane): Perennial. 2 feet tall x 2 feet wide. Sun to part shade. Well-drained, moist to dry soil. Lovely and abundant daisy-like, bluish lavender blossoms go nearly all summer. (pictured below)

Erigeron speciosus

◊ Holodiscus discolor (oceanspray, aka cream bush): Fast growing, very attractive deciduous shrub. 8-16 feet tall x 8-12 feet wide (larger on protected sites, smaller on windy, harsh sites). Sun to part shade (intolerant of full shade). Not fussy about soil; moist or dry. Drought tolerant when established. Lavish, feathery plumes of creamy-white flowers in early to mid-summer. Nice for hedgerows. Controls erosion.

 

◊ Lupinus polyphyllus (large-leaved lupine): Perennial. 2-4 feet tall x 2-4 feet wide. Sun to part shade (intolerant of full shade). Moist soil preferred but will tolerate short dry periods. Tall spikes of bluish-purple, pea-like flowers. (pictured, right) Lupinus polyphyllus

◊ Sedum spathulifolium or S. oreganum (stonecrop): Perennial. 1-4 inches tall; spreads slowly. Sun to part sun (afternoon shade is welcome). Well-draining, gritty, lean soil. Bright yellow star-shaped flowers. Nice for rock gardens. Not a ground cover for foot traffic. (S. spathulifolium pictured below)

◊ Symphoricarpos albus (snowberry): Deciduous shrub. 4-6 feet tall x 4-6 feet wide. Sun to mostly shade. Moist or dry soils; tolerates heavy soils. Drought tolerant when established. Tiny, paired, pink, bell-shaped flowers. Eventually forms a thicket. Controls erosion.

◊ Tiaralla trifoliata (foam flower): Perennial. 8-14 inches tall x 1-14 inches wide. Shade to part shade. Spreads very slowly by rhizomes or seed. Needs moist, well-draining soil rich in organic matter. Panicles of white to pale pink flowers bloom from late spring to late summer. More details here.

Sedum spathulifolium with syrphid fly

 

Copyright 2015 Eileen M. Stark

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Posted on by Eileen Stark