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.

 

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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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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Ban Neonicotinoids in Portland

painted lady butterfly

The most widely used pesticides in the world, neonicotinoids (often called neonics) are a highly toxic, pervasive, relatively new class of insecticide. Following massive bee die-offs from neonic applications in the U.S. and Canada, last year Eugene became the first U.S. city to ban the use of neonics from city property. Similar bans in Seattle, Sacramento, and Spokane quickly trailed, and now Portland’s City Council is considering comparable—and crucial—affirmative policy at the local level, since higher government continually fails to offer protection from this growing environmental threat. The U.S. Fish and Wildlife Service decided last year to phase out neonics in its wildlife refuges, making it the first federal agency to restrict neonics, but the U.S. Environmental Protection Agency has yet to act.

Hundreds of studies indicate that neonics are wreaking environmental havoc: They not only disastrously kill or debilitate native bees, honeybees, and other pollinators like butterflies and moths, but also other ecosystem members such as birds, aquatic species, and mammals. Neonics are systemic, taken up through a plant’s vascular system and exuded in the pollen and nectar. Even miniscule amounts adversely affect central nervous and immune systems, cumulatively and irreversibly. If a victim such as a bumblebee isn’t killed outright, its failed immune system will succumb to ostensibly “natural” parasites and pathogens like Bombus bifarius on Aster foliaceusfungal, viral or bacterial infections. Birds—the majority of which consume and feed their young insects—may be poisoned directly or go hungry due to a lack of insect biomass; scientists predict widespread reproductive dysfunction in birds due to neonic exposure.

Since neonics are water soluble, they are very prone to runoff and groundwater infiltration where they accumulate and persist for any years. Aquatic contamination has reached toxic levels in some areas and is expected to cause serious and far-reaching impacts on aquatic food chains.

The cumulative, persistent, and irreversible nature of neonics ought to raise some serious red flags. Human children may also be at risk to this neurotoxic class of pesticides due to their developing bodies and immune systems and tendency to be exposed to problematic substances while playing outdoors.

What we can do

We can voice our support for the proposed ordinance—which also recommends that local retailers label plants, seeds, and products containing neonics—by contacting Portland’s mayor and commissioners by March 31. Personally, I’d love to see this ban go further, as would Commissioner Amanda Fritz, but a ban on city property is a good first step.

We can also take action at home by eliminating pesticides and growing beautiful wildlife-friendly gardens. Besides chemicals, another major threat to wildlife is the lack of natural foraging areas. In our own yards we can attract and feed pollinators by including a variety of nonhybridized—preferably native—plants that will collectively flower from early spring through fall. Native plants that naturally occur in our region are best for all indigenous fauna because they supply the food and shelter that wild species require to survive and they need no synthetic pesticides or fertilizers.

 

© 2015 Eileen M. Stark

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