Can We Save Oregon Ash Trees?

By now you’ve likely heard that identification of the dreaded emerald ash borer (EAB) has been confirmed in Washington County, Oregon. The Oregon Department of Agriculture believes that the infestation has been in that county for at least three to five years. The outlook is grim.

Of northeastern Asian origin, the EAB is a small green beetle in the Buprestidae family which feeds on members of the olive family (Oleaceae), especially ash trees (Fraxinus species). Adults feed on leaves and females lay their eggs in bark crevices. Eggs hatch in seven to ten days and larvae burrow through bark to living tissues where they feed, eventually cutting off the flow of water and nutrients, which causes a slow death. Adults emerge in one to two years and typically travel only about a half mile afterwards.

In its native range, this beetle is typically not found in high numbers and does not cause significant damage to native trees. However, outside its native range it is extremely destructive to trees indigenous to North America or Europe.

The EAB is now considered to be the most destructive forest insect to ever invade North America. First detected in Michigan in 2002, it has spread through much of the U.S. (36 states and the District of Columbia). Though harmless to people and other animals, it has proven deadly to all ash species in North America, including the native Oregon ash (Fraxinus latifolia), naturally found west of the Cascades in southern British Columbia, Washington, Oregon, and northwestern California, as well as central California and the Sierra Nevada.

Spread throughout the country has been mainly by the movement of infested firewood, logs, chips, and nursery stock. Movement of emerald ash borers and their host material has been, until recently, regulated by the USDA under a federal domestic quarantine. The quarantine for emerald ash borer was repealed in January 2021.

The Oregon ash tree is currently relatively common and is a significant component of riparian forests; it is the only native ash tree in the Pacific Northwest. It is widely used for stream restoration due to its wide and spreading root system that stabilizes soil, controls sediment, and moderates stream temperatures. Widespread loss of these beautiful, long-lived trees will affect water quality (including higher stream temperatures) and change the wildlife species composition of their ecosystems, causing harmful effects on species dependent on those ecosystems.

How to help
Learn now to identify ash trees and trees that resemble them here.

If you have ash trees or know of some, familiarize yourself with the basic signs and symptoms of emerald ash borer. Reports may be made at https://oregoninvasiveshotline.org/reports/create

Also check out this article. Robert Haight, a Forest Service researcher in St. Paul, Minn., proposes a strategic approach which involves identifying beetle-infested ash trees before they show signs of damage. “One way, he says, involves searching for woodpeckers. The emerald ash borer hides its eggs in bark crevices and tunnels deeply within trees — invisible to humans, but not to woodpeckers. They pick at the tree’s bark, searching for tasty grubs.” So please keep an eye out for our friends, the woodpeckers, foraging on Oregon ash trees.

UPDATE February 2023: The Oregon Department of Forestry has collected 900,000 Oregon ash seeds; it hopes to find trees resistant to the borer in that collection. Read about it here.

More info and brochures: https://www.oregon.gov/oda/programs/IPPM/SurveyTreatment/Pages/EmeraldAshBorer.aspx

Oregon’s Readiness and Response Plan: https://static1.squarespace.com/static/58740d57579fb3b4fa5ce66f/t/60772a17647ad466155f74a7/1618422303582/March+2021_EAB.pdf

Xerces Society: https://xerces.org/blog/how-to-spot-and-slow-emerald-ash-borers-in-your-community?fbclid=IwAR0iLt9u-DQlfETCOEUMet6F86Hmr8SWWYUIb-2-4G7PrItVfgYf7JVL-Eg


© 2022 Eileen M. Stark

Five Ways to Make Your Yard More Biodiverse

Olive clubtail dragonfly resting on Mountain ash (Sorbus scopulina).

 

Every 30 seconds in the United States, a football field-sized chunk of natural area disappears due to development, according to research from the Center for American Progress. Most of the natural areas lost in the past two decades were on privately-owned land, which accounts for about 60% of all land in the country. Clearly there’s much work to be done, since only 3% of protected areas in the U.S. are on private land. Currently, only 12% of all U.S. land is protected, which is very bad news for biodiversity. 

Scientists see the goals set by the International Convention on Biological Diversity — protection of a mere 17% of land and 10% of oceans by 2020 — as completely inadequate to handle the Sixth Mass Extinction and the climate crisis. To stop the crumbling of biodiversity — defined as all the organisms on earth, well as the diversity of ecosystems in which they are found, and the genetic diversity within each species — efforts are now behind “30×30”, a global goal to protect 30% of Earth’s land and water by 2030.

President Biden issued an executive order soon after taking office that requires agency leaders to submit input and strategies for how the feds can conserve at least 30% by 2030. Reversing the cuts made by the Trump administration and targeting expansive areas will certainly have the quickest effect, but all important habitat ought to be saved or restored. If you feel hopeless or sickened by the extinction and climate crises made worse by unrestrained development, even a 30 by 30 foot space at home will help. We can’t put it off any longer.

Here are some objectives as you move forward: 

1. Focus on local native plants after removing invasives. There’s nothing terribly wrong with growing a few of your favorite plants—for example, I love certain clematis vines and irises, and I grow organic food to eat. But those plants don’t provide much, if any, benefit for wildlife, so a large portion of the remaining plants I’ve chosen are native species, most of which belong in my area and might grow together in their natural state. Besides being low maintenance (when properly sited), they are absolutely essential to creatures who developed special relationships with them over millennia.

Native species are superior to introduced plants not because they’re trendy or due to some prejudice or because I say so. Simply put, native plants depend on native wildlife and vice versa (when they are in the appropriate place—that is, areas where they evolved together). They’re adapted to local environmental conditions and their value is not based solely as a resource for humans or on appearance (although their beauty is remarkable!).

Plant diversity is strongly associated with species richness, including healthy insect-dominated food webs. As the essential structural and functional base of many of the world’s ecosystems, most insects are “specialists”—they can only survive with certain species of plants that they evolved with (as opposed to “generalist” species that can use many plants). For example, butterflies and moths need certain host plants that provide food for their young, and many native bees forage for pollen only on specific plants at specific times of year. Myriad other insects are able to use only specific native plants; if those plants aren’t around, the insects’ decline or disappearance adversely impacts ecosystems and other animal populations since specialist and generalist insects and other arthropods supply food for other wildlife. Besides habitat destruction and climate chaos, insects are challenged by additional stressors, including insecticides, herbicides, introduced species, and light pollution. To make things worse, stressors often happen simultaneously. A 2019 global review revealed that 40% of insect species could become extinct in the next few decades, with a staggering 2.5% decline in insect biomass per year, and warned of a catastrophic impact on the earth’s ecosystems. In 2020, researchers found that Earth lost more than 25 percent of land-dwelling insects in the past 30 years

Growing natives is an act of compassion for wildlife at our mercy. It helps to think of animals as individuals with emotions and personalities, not just species. Like us, they want to avoid suffering and live a decent life, and most need native plants in order to do so. Animals such as birds and frogs that eat insects directly are of course negatively affected, but other species are as well. Bobcats, for example, are obligate carnivores, but they need native plants since they typically eat animals that consume insects or plant matter. 

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.

2. Minimize lawn and be bold when it comes to sizing garden beds. The more space we allocate for native plants, the better. Lawn is an unnatural monoculture that provides almost no support for wildlife, so if it’s not needed, let it go. You can remove it with a sod cutter or spade, but to preserve precious topsoil, cut it short, then cover it with a half dozen layers of overlapping newspaper or a layer of cardboard with holes punched in to ensure drainage. Cover with leaf compost and allow it to break down over many months.

To get ideas for plant selection and how to arrange and space those plants, look to nearby natural areas that support local native plants, inquire with your local native plant society chapter, and check out my book (if you live west of the Cascades). Plant long-lived trees and shrubs for carbon sequestration and habitat, as well as privacy so that unnecessary fencing may be removed, allowing for a contribution to wildlife corridors that connect. Add associated understory plants, including ground covers that offer the best mulch

Speaking of space, growing perennials for pollinators’ sakes means providing at least several plants of the same species that are planted fairly close to each other so that pollinators can easily find them and so there’s enough of a particular flower’s nectar/pollen to go around. But spacing them evenly, in perfect clumps, isn’t necessary and often looks contrived, and lining them up like veggies in a kitchen garden is even worse, aesthetically speaking. Take a walk in a natural area and you’ll find perennials and other plants with an array of spacing—some close together, some further apart; most mingle with other species that they evolved with. Irregular drifts may occur, as if nature took a paintbrush to create rhythmic splashes. Repetition of plant groupings will result in a natural look and more habitat. Be sure to provide at least a couple of species that flower in unbroken sequence from early spring until fall.


3. Avoid pesticides and use organic methods. It’s imperative to not use pesticides (insecticides, herbicides, fungicides, etc.) and chemical fertilizers to prevent harm to beneficial creatures above and below ground at home and prevent toxins from entering waterways and killing downstream. The Environmental Protection Agency has registered more than 18,000 pesticides for use, and more than 2 billion pounds of pesticides are sold every year in the U.S. Pesticides are pervasive in aquatic and terrestrial habitat throughout the country and threaten the survival and recovery of hundreds of federally listed species. They don’t stay put and can kill non-targeted species, decrease biodiversity within soil, are linked to a decline in nitrogen fixation, mess up the complex balance between predator and prey species in food webs, require fossil fuels, and involve heinously cruel experiments on animals. And, the U.N. tells us that about 200,000 people die each year from pesticide exposure. Chemical fertilizers are also very problematic since they kill soil microbes and pollute groundwater and waterways, leading to dead zones, among other damages.

4. Minimize water runoff and maximize carbon storage. There’s much we can do with the water that enters our landscape, and it doesn’t have to take much effort. It may help to think of our yards as mini-watersheds and ask what we can do to make sure the water that leaves our properties is clean and won’t harm other species.

Rain gardens can collect water — from downspouts or hard surfaces where water accumulates — and slow the flow of water, cleaning it as it slowly soaks into the ground and recharges aquifers. Other elements like bioswales, permeable paving, coniferous trees, and even rain barrels can manage water responsibly in our landscapes, reducing runoff that overwhelms storm drains and pollutes waterways. But it’s the plants themselves (along with soil) that effectively filter water and store carbon. Fully and diversely planted gardens — that include long-lived large trees, shrubs and lower plants — are best at cleaning water, preventing runoff, and sequestering carbon; more so than lawn or beds that are mostly wood chips. 

Halictus ligatus on Erigeron speciosus.

Although keeping your soil covered (with plants or mulch) is a good thing for carbon storage, moisture retention and erosion control, always leave some areas with bare soil (fallen leaves and small amounts of light compost are okay), particularly in areas that face south or east. Here’s why:  70% of native bees (such as this “sweat bee,” Halictus ligatus, shown) nest in the ground (the rest raise their young aboveground in cavities, stems, tunnels or crevices). Using thick layers of wood chips, bark dust, or other such substances prevents them from being able to create their nests and if applied after nests are complete, entombs and kills the developing bees.

Also, if you grow veggies, keep tillage to a minimum, if at all. Tilling soil speeds up the decomposition of organic matter, causes erosion, releases carbon dioxide into the air, exposes weed seeds to light, destroys mycorrhizae hyphae, and generally makes soil less fertile. Unnecessary fertilizer will also release more carbon. 

Erosion concerns? Choose native plants with dense, fibrous root systems to control erosion on slopes. In the Pacific Northwest, depending on your location and conditions, consider Douglas-fir, big-leaf maple, vine maple, Oregon white (Garry) oak, madrone, serviceberry, salal,  kinnikinnick, red-twig dogwood, oceanspray, tall Oregon grape and Cascade Oregon grape, western mock orange, red-flowering currant, snowberry, western sword fern, inside-out flower, and many others.

Bushtit nests require moss, spider silk, and other natural substances.

5. Add natural elements and be lazy. Wild species need secure, dry places to spend the winter, pupate, or seek cover during bad weather, and places to raise their young:  (1) Leave the leaves on soil. (2) Include rotting logs and other dead wood in shady spots to supply the perfect home for certain invertebrates and fungi. (3) Introduce brush piles to provide shelter and maybe even nest sites for some birds. (4) If you’ve dug up rocks from your soil, create smooth rock piles or stone walls without mortar to provide cover for wildlife like amphibians and reptiles, as well as arthropods. Making all these elements as large as possible and placing them in quiet areas works best. (5) If you must “clean up,” don’t do it in fall or winter. Instead, wait until late spring and do as little as possible so that those taking cover won’t be disturbed and so that birds can find building materials for their nests, such as moss, lichen, twigs, spider silk, and dried leaves (see bushtit nest, pictured above). If all this sounds messy, it is, but it’s also easy and exactly that characteristic that supports the greatest garden biodiversity! 

Last but not least, give wildlife a drink. All animals — from birds and dragonflies to frogs and salamanders — need water, so include a gently sloping bird bath or more elaborate water feature like a pond, and perhaps a plate full of watery gravel to help creatures thrive. Although the latter is most important during dry weather, birds need water year round to keep their feathers clean and waterproof. Since many urban streams have been buried, wetlands drained, and drought is upon us, it’s the least we can do.

Golden-crowned kinglet and Townsend' warbler.

© 2021 Eileen M. Stark

Green Corridors Begin at Home

“Is the deer crossing the road, or is the road crossing the forest?” 

To survive, most wild fauna must be on the move—to find food, water, safe shelter and breeding sites, mates, and, for some species, to migrate. But wildlife habitat is increasingly destroyed, degraded, or fragmented into small, isolated patches—by human-made barriers such as buildings, fences, lawns, and roads—which intensify their struggle to survive.

Habitat loss is one of the main threats to wildlife. More people and development mean less natural habitat, while inaction on the climate crisis forces animals to relocate. Today, more than ever, habitat connectivity needs to be restored and wild ones’ daily and seasonal movements or migrations protected.

Habitat connectivity is defined as the degree to which the landscape helps or hinders animals’ movements, as well as other ecological processes, such as seed dispersal. Whether they’re called conservation corridors, green corridors, habitat corridors, or wildlife pathways, their purpose is identical: To provide native habitat as seamlessly as possible, so that wildlife populations may be connected instead of separated. Even in deteriorated landscapes, such corridors boost biodiversity, allow genetic exchange between populations, and may even help ease the reestablishment of populations that have been decimated, isolated, or previously extirpated.

Recognizing that every front, back and side yard—even those within urban areas—is part of an intricate ecosystem that could support a great number of species is the first step toward encouraging rich, natural diversity. When “real” or “naturescaped” yards link directly to others like them, they help mitigate some of the effects of fragmentation, a huge threat to biodiversity. In general, urban and suburban areas are highly fragmented. Wildlife corridors are essential, especially for animals with large ranges.

You might be wondering, “Aren’t large-scale habitat connectivity projects happening?” or “Isn’t my yard too small to help much?” Yes, and no: The big projects are vital and projects such as underpasses and overpasses that help wildlife cross busy roads (that kill or injure many millions of animals each year) are multiplying, thanks to recent legislation in some states, as well as the federal Wildlife Crossings Pilot Program that provides funding. But also crucial are all the little spaces that—even if they’re not in the path of pronghorn or monarch butterflies—when added up, create interconnected networks. As I wrote in my book, “To be most beneficial, gardens need to connect—to each other and to the larger world—to provide continuous passage for wildlife and allow each garden to work and blend harmoniously with others nearby. A single naturalistic garden has benefits, but when in proximity to others like it, its worth multiplies.” Studies show that “the role of corridors is crucial for enhancing biodiversity in green spaces such as domestic gardens … results clarify the effectiveness of corridors in urban landscapes and have direct implications for the ecological management of cities.”

What to do? Whether you’re an avid gardener or someone who cares about dwindling wildlife, you can take positive action to help your property, balcony, or communal green spaces act as safe stepping stones within a green corridor that supports wildlife. It’s something that we can do despite (or perhaps because of) the heinous weakening of environmental protections by certain politicians over the past few years. And, it’s effective, rewarding, and usually fairly easy if you plan ahead.

Some basic tips:
Grow a diversity of locally native plants, and be sure to remove exotic invasive plants as much as possible beforehand (incrementally if they are used by wildlife). Your yard doesn’t have to be exclusively native, but when planted appropriately, the trees and shrubs that evolved in your area are especially important for supplying food, shelter, and possibly nesting sites.

Don’t fence them out (or in). When we moved into our house, one of the first things we did outdoors was remove two gates to our backyard. They served no purpose and I wanted to make it easy for four-legged fauna to come and go. While there are situations where fencing is helpful (for a dog run, to protect a veggie garden, or to prevent a little one from wandering off), many urban and suburban back yards are separated by tall, unattractive fencing that does nothing useful except provide some privacy.

Instead of impassible fencing (that also greatly diminishes air circulation around plants and, in the case of wooden fencing, wastes trees), think living, breathing native shrubs—either in an unpruned hedgerow or more naturalistic plantings—to provide privacy. Besides being much more aesthetically pleasing, shrubs alone provide food and shelter for wildlife, shade and carbon sequestration, and contribute greatly to green corridors. Unlike fencing, shrubs provide privacy but allow small animals to pass under, through, or along, from garden to garden. If your yard is tiny and you must add a narrow barrier, consider wooden lattice fencing with large openings, upon which (noninvasive) vines could grow (but don’t do this if you live where megafauna could get caught in it).

Some types of fencing can brutally kill or ensnare wildlife (and even people), often at nighttime. Avoid metal rail fencing, any spiked fencing, and all plastic netting. When not in use, take down volleyball and soccer netting.

Rethink manicured yards. Highly pruned, overly tidy, leafless, lawn-centric yards sustain very little life and are high-maintenance. Instead, create a chemical-free native wildlife garden that is more relaxed (some might say “messy”) and has the ability to support much more life. If you’re worried about what the neighbors will say, add some signs of human intention in the front: (a) Create interesting structure by varying the heights of plants so there is a connection from tall trees to ground cover—this not only looks nice, it’s great for wildlife; (b) Choose shrubs that can grow to their full potential without crowding each other out, hiding your doors or windows, or encroaching into pathways—all of which will eventually require harsh pruning; (c) Instead of one plant here, one plant there, plan for a rhythm by growing perennials in drifts or uneven clusters, and then repeat them elsewhere in your yard (this is also highly beneficial to wildlife like pollinators who need multiple plants to feed on); (d) Consider adding step stone paths, bird baths, strategically placed half-buried rocks, sculpture, or nest boxes (if appropriate), but don’t overdo it—few “focal points” are better than many. Don’t add landscape lighting, which is deleterious to living things.

Avoid “ecological traps” and minimize danger. When we grow native plants, minimize lighting, leave the leaves, add a water source and other positive elements to our yards, one of the wonderful outcomes is the increase in wild visitors. But no matter how well-meaning our actions are, “ecological traps” may be created when we make our yards welcoming to wildlife but don’t address the human-induced hazards that lurk nearby. When we design for biodiversity we must consider not just adding habitat, but also what we might inadvertently set them up for, such as being preyed upon by cats or dogs, or injured or killed by windows or some other hazard in our yard. Of course we don’t want to eliminate windows or companion animals, so we have to embrace adaptations that allow us to keep them and protect wild ones at the same time.

In other posts I’ve addressed the disastrous effect that reflective windows have on birds as well as the consequences of light pollution. Another lethal issue is free-roaming cats. Certainly not all cats are avid hunters, but many are, and it’s up to us to take responsibility for their actions. If you already have a kitty who’s been spending a lot of time outdoors, it’s going to be difficult—or even cruel—to suddenly lock him up and throw away the key. Cats are obligate carnivores, so it’s not their fault that they hunt, or want to. For those with unbreakable habits, consider limiting outdoor adventures during baby bird season (late spring to mid-summer) and at those times of the day when birds are actively feeding (typically early morning and late afternoon), and use hanging birdbaths instead of grounded ones. The next time you adopt a new cat, keep them safely indoors but offer a place to get fresh air, like a catio. Dogs, of course, may also be problematic, especially in areas where sensitive wildlife live or nest on the ground, such as fragile amphibians and reptiles.

Minimize hardscape. Unnatural hardscape does nothing for wildlife. Every time we remove hardscape and replace it with, say, regional native plants, dead wood, a water source and other beneficial elements, we help wildlife thrive. Minimizing it in your yard also helps reduce stormwater pollution, improve water quality, and mitigate the impacts of climate chaos.

Urge urban planners and park space advocates to plant native species. Despite native plants’ benefit to ecosystems and humans, they aren’t often added. A typical city park, for example, contains large expanses of lawn and some isolated trees (often non-native). Ecosystems are much more complex and may include tall trees, smaller trees, large and small shrubs, perennials and grasses, dead wood and fallen leaves, which support a large number of species. Creating native beds surrounding single trees, or at least within designated areas, will add complex layers without eliminating picnic space.

Finally, talk with your neighbors. Imagine if everyone’s yard was connected—botanically speaking—to the one next door, preferably without fences and gates. Then imagine that these connections continue from neighborhood to neighborhood and go on for miles, finally reaching a large natural area that’s even more supportive. Some neighbors may find your ideology beyond their grasp, but others may surprise you. Some people simply may not know about the deadly hazards of development and exotic plants, and speaking with them—or at least setting an example—may help to open their eyes and hearts.

 

© 2020 Eileen M. Stark

Earth to Humans: “Wake Up!”


Fifty years ago today, my U.S. senator at the time, Gaylord Nelson, designated April 22 as Earth Day, a day for Americans to speak out about environmental crises. The “conservation governor” of Wisconsin for two terms and U.S. senator for 18 years, Nelson struggled at putting environmental issues in a prominent place in politics, but eventually succeeded. Besides authoring legislation that created a national hiking trails system and the 2,100-mile Appalachian Trail System, he was deeply involved in important bedrock environmental laws including the Wilderness Act, Clean Air Act, Clean Water Acts, Federal Pesticides Act, and National Wild and Scenic Rivers Act.

Although Nelson came up with the idea, it was ordinary citizens who made Earth Day what it was and what it has become, through grassroots political action. The first Earth Day in 1970 was, to date, the largest demonstration of any kind in the country. The goal was an “environment of decency, quality and mutual respect for all other human beings and all other living creatures.” Clearly, he believed in a better future for the planet and all its residents.

Which brings me to the strange times that could become the new ‘normal.’ While it’s very difficult these days not to focus on how the pandemic affects us, climate chaos and widespread exploitation of animals continues unabated. The link between animal and human health is clear; we must remember the other gentler members of the planet with which we are connected—for both their sakes and ours. Although we are just one species on Earth, we have — by far — the biggest impact. 

I’ve always known that wildlife ought to be left alone, to live the natural life that they evolved to live. Wild animals fear us, don’t want us around, and certainly don’t need us. And when we invade and destroy their habitat, the harm that can come to them — and us — is appalling, to say the least. As if we need proof, one study demonstrates that as humans encroach into species-rich habitats — for development, road building, hunting, mining, etc. — biodiversity declines, wild landscapes disappear, and exposure to ‘new’ microbes increases. Many diseases, like Ebola, SARS, HIV, Lyme disease and others, arose that way. Scientists tell us that around 70 percent of emerging infectious diseases in humans are of zoonotic origin, and nearly 1.7 million undiscovered viruses may exist in wildlife.

Our current pandemic is similar to other unknown viruses that have come about under similar circumstances — that is, when humans steal various innocent wild animals from their natural homes and cruelly toss them together in horrendous markets. It’s almost as if the uncontrollable pathogens are responding to human actions that have put harrowing pressure on the natural world, leading to damaging and widespread consequences that put all life — human and non-human animals, and even plants — at risk. Failure to take care of our home and other species’ natural homes also means a failure to take care of ourselves.  

The media has mostly focused on the connection between pandemics and “wet markets” (where miserable live animals are slaughtered and sold). COVID-19 did likely originate in a live animal market in China, but these markets are not the only places that pose dangers, or where animals suffer intensely. Scientists now believe that the current pandemic started as a result of wildlife trafficking and that the disease probably originated in those wonderful pest-eaters — bats — and moved in a live animal market to an intermediary host — possibly the highly endangered pangolin, the most trafficked mammal on earth — and from there the disease jumped to humans. Although some locales have banned the sale of wildlife for food, there are loopholes for alleged medicinal purposes and won’t trafficking just go underground?

Moreover, confining enormous numbers of tortured, domesticated animals close together in factory farms essentially creates breeding grounds for pandemics. Studies have linked factory farming (also one of the largest sources of methane emissions) to more virulent, faster-mutating pathogens. The same animal ag corporations that worsen the climate crisis abet the creation of new, deadlier diseases at high volume that can adapt to humans.

And let’s not forget the indirect destruction, killing and other environmental disasters, such as broken heat records, dying coral reefs, and uncontrollable wildfires. Both climate chaos as well as its causes — rampant development, deforestation, animal agriculture, and other ecosystem destruction — must end, since all force free-living wildlife into contact with people.

As Carl Safina writes, it’s only going to get worse and next time we could face unimaginable “lethal chaos.” But we’re nearly there, when it comes to how we’ve caused crossover contamination to other species. One example: The Siberian (or Amur) tiger, one of the six remaining tiger subspecies and one of the most terribly endangered due to poaching and habitat loss caused by humans, may go extinct soon due to the deadly canine distemper virus (CDV). CVD was first described and likely originated in South America where the closely related Eurasian human measles virus raged in the 1500-1700s. Those epidemics “likely facilitated the establishment of CDV as a canine pathogen, which eventually spread to Europe and beyond.” The virus is suspected to have caused the deaths of thousands of Caspian seals during outbreaks in 1988 and 2000; it nearly exterminated the black-footed ferret, and has decimated Africa’s wild dog populations. CDV hit Serengeti lions in 1994, when the epidemic killed a third of their population — nearly 1,000 animals at once — as well as a huge number of leopards, bat-eared foxes, and hyenas. Additionally, global animal trade spreads the often fatal ranaviruses, which infect amphibians, reptiles and fish, and one reason for the global decline of wild native bees are diseases that spillover from managed, commercial bumble bee or honeybee (Apis mellifera) colonies that suffer from a range of exotic and high-impact pathogens.

The largest mass extinction (since the dinosaurs)
Pandemics may happen more often when climate change is unabated. For example, the Ebola epidemic in West Africa coincided with cutting down forests for agriculture. Bats who lost their homes were forced into new places when their habitat was destroyed. Changing weather patterns also alter vectors and the spread of disease.

According to a new study, as early as the next decade, many more animal species than previously predicted will collapse if greenhouse gas emissions are not lessened, and it won’t be gradual. Nearly all species and all regions will be affected and abrupt collapses in tropical oceans could begin soon. Coral bleaching events have already begun, and collapse of highly diverse tropical forests ecosystems could follow just several decades later. One example that may speed up: As much as half of the planet’s 6,000 amphibian species are in danger of extinction due to a global pandemic caused by wildlife exploitation. Chytridiomycosis, a fungal disease that’s found on every continent except Antarctica, is quickly pushing some species toward oblivion; some, like the Panamanian golden frog are thought to be gone. The disease’s spread can be traced back to the commercial trade in exotic animals and is exacerbated by the climate crisis.

If we don’t learn now, will we ever? We certainly can’t stop every negative aspect of modern human society, but we can proceed in a more gentle, compassionate, sustainable way to reduce our ecological footprint. Not only will it lessen climate change and promote conservation, it will improve our health.

© 2020 Eileen M. Stark

Gardeners Can Help Combat the Climate Crisis

Hermit warbler


The man with a pained expression said that he was worried about the birds.
And all I could do was nod.

During the Q&A following a presentation I recently gave in Portland, many attendees expressed concern about climate chaos. One mentioned the change in hardiness zones, while another mentioned driving north into Washington State and seeing countless trees apparently near death. Others wondered if they should consider modifying their plant selections since studies show that native plants are on the move, northward or to higher or lower elevations. But of course their populations can’t shift fast enough, and at some point in the not-too-distant future, they’ll run out of places to go. Ecosystems will collapse, especially in extreme environments, and their innocent members will suffer.

I cringe whenever the subject of dealing with anthropogenic climate change comes up because I believe we ought to be fighting it in any and every way we can, not giving in. I have to hold back tears when I read news accounts that document the devastating and irreversible changes that are already taking place. Climate change is the most pressing environmental problem of our time (besides its close cousin, overpopulation) and every human ought to be troubled by it, especially because it could have been remedied 30+ years ago.

Needless to say, we must drastically cut greenhouse gas emissions if we’re going to keep climate warming at a safe level (below 1 degrees celsius), and we need to do it quickly if we want to avoid catastrophic change. As individuals, we can drive and fly much less (walk or grab a bike or bus or train) and eliminate or at least cut our use of meat and other animal products, toward a much healthier plant-based diet.

We also need to plant trees, price carbon emissions, subsidize clean energy and close coal plants and stop drilling, avoid plastics and palm oil, and require “zero-deforestation” supply chains, among other things. 

Removing carbon dioxide, the primary warming gas, from the atmosphere is as essential as curtailing emissions; the National Academy of Sciences estimated that ten gigatons (one gigaton is a billion tons) of CO2—about one fifth of all emissions—could be taken from the air each year, simply by growing more trees. In addition, taking much better care of the soil could have an immense impact, since the planet’s soils were once a gigantic carbon sink that have lost between 50 and 70 percent of their original carbon stock. It can be put it back where it belongs if we restore degraded and eroded land and curtail deforestation as well as destruction of peatlands.

Try it at home

One of the most immediate and tangible ways we can help fight climate change as individuals is to conserve native habitat—by keeping it intact and healthy—and restore native habitat. It makes climate sense and anyone with a yard can do their part at home. It will also build a greater buffer for plants and animals to survive changing conditions. Here are a few tips:

♦ Lose the lawn (or at least most of it). Of the 42 million acres of lawn in the U.S., a massive chunk could be replaced with regional native plants. Besides lawn being a wasteland where other, more positive things could grow, lawns are maintained annually with 300 million tons of synthetic, fossil fuel-based fertilizers that, besides polluting waterways, add to air pollution as they break down. The same goes for fossil fuel-based pesticides. And two-stroke gasoline-powered lawn equipment burns more than 800 million gallons of gasoline (and spills, literally, 17 million gallons) each year while their products of combustion cause high levels of hazardous air pollutants and CO2. If you must have lawn, mow high, don’t water, and leave grass clippings to fertilize the soil and add carbon.

♦ 
Use push mowers, rakes, brooms and other no-emission tools. They take a little more effort than motorized tools, but can’t we all use a little more exercise?

♦ Plant more native trees and shrubs. Due to their size and typically long life spans, trees and large shrubs—particularly those that are long-lived—remove more heat-trapping CO2 from the atmosphere than other plants. Whenever possible, choose plants from the native plant community local to your area to help them thrive in changing times. Plant communities are, essentially, loose associations of interdependent species that belong together because they’ve adapted, over thousands of years, to have similar needs and tolerance for the existing soil type, topography, precipitation, humidity, sunlight, and wildlife of an area. They are defined by the species that are most obvious (largest or the most abundant) in a given environment. Besides looking good together above ground, the plants often have symbiotic relationships, such as by sharing moisture and nutrients underground, with the help of mychorrizae. They communicate with chemicals through the soil and above ground and interact through competition and other ecological relations. To achieve summer shade and reduce or eliminate the need for air conditioning, grow large trees on the southwest or west side of your house (10 to 30 feet away) to block hot afternoon rays (second best place is the southeast or east side). Appropriately placed trees also offer protection from winter winds, which can help with home heating._MG_1052 Big-leaf maple branch

♦ Grow your own fruits and vegetables organically. Besides being incredibly healthful, fresh, and tasty, home edible gardening eliminates the fuel used to transport food. If you can’t grow your own, buy certified organic foods whenever possible. No-till organic farming is the best agricultural practice for wildlife and for sustainable land management, particularly through the enrichment of soil microbial activity that increases mineral exchange between plants and soil, which promotes carbon fixation. Since soils are the basis of food production, preserving their quality is critical, even if organic farming is not the most productive.

♦ Compost at home. Organic waste that decomposes in anaerobic landfills creates methane, a heat-trapping gas that is 23 times more potent than CO2. But when we compost in the presence of oxygen, methane production is minimized. Composting yard clippings (without weed seeds), leaves and vegan food scraps (roughly a 1:1 ratio of “greens” and “browns”) produces a nutrient-rich soil amendment that reduces the need for fertilizers while helping the soil store more carbon. Compost made with only fallen leaves also produces a nice soil amendment that’s good at improving soil structure and microbial activity.

Keep your soil healthy. Allow fallen leaves, bark, twigs, lichen, and downed wood to remain on soil to protect it and add nutrients.

 

© 2018 Eileen M. Stark

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Remove Invasive Plants: It’s Good for Wildlife and Gardens

English ivy (Hedera helix)

A little neglect goes a long way (English ivy takes over).


I’m embarrassed to admit
that when I first moved to the Pacific Northwest in 1990, before I knew much about regional native plants, I thought that foxgloves were native plants. Why? Because I encountered them in natural areas. Luckily, I know much better now and—with the exception of some infrequently traveled trails in remote corners of the world—I cannot remember a hike where I haven’t encountered invasive plants (and sometimes a terribly large number of them). Areas close to urban areas are hardest hit, but even ecosystems far from the madding crowd can suffer from their effects.Digitalis purpurea

Invasive plants are nonnatives that were—and continue to be—brought here either intentionally by the nursery trade (or agriculture), or accidentally (as packing material and such). Thousands of species have been brought to North America, and many of ours have been sent abroad. All this rearranging of the earth’s flora started innocently enough centuries ago, but experts fear that it’s reached a point where biological diversity is severely threatened and essential interactions, like pollination, are damaged. Foxglove (Digitalis purpurea), as lovely as a biennial can be, may not be one of the worst offenders, but it doesn’t stay put with its countless tiny seeds, and shows up in places it doesn’t belong, basically making life miserable for the native plants that do. More problematic species often reproduce in several ways: For example, Himalayan blackberry and English ivy (shown in top photo) and its cultivars spread via rooting stems and by fruits eaten and dispersed by wildlife. Both suppress and exclude native vegetation and form dense monocultures that are unsuitable as wildlife habitat. English ivy is capable of one other feat, if left alone long enough: Killing entire trees.

Of course, not all nonnative plants pose horrendous problems, but those that do run amok are able to because whatever keeps them in balance in their native land—soils, predators, pathogens or weather conditions—are lacking here. Consequently, they do so well that they’re able to spread fairly easily from yards or agricultural areas into natural areas that support native species that can’t compete; the natives have no defense, become overwhelmed by the newcomers, and die out. This is particularly devastating for uncommon or endangered plants close to extinction. In addition, the spread of invasives (plant, animals, and pathogens) has economic ramifications.

Deadly for wildlife
While habitat loss due to deforestation, urban sprawl, livestock grazing, and agriculture is the greatest threat to the variety of life on Earth, invasive plants contribute greatly to the tragic loss of biodiversity. Since native plants are essential for native fauna (especially insect herbivores, most of which are specialists that can only use a certain plant or plants due to their chemical makeup), when natives are gone, so too are the herbivores and the higher life forms that feed on them. And, needless to say, fauna use native plants for other essentials, like nesting habitat and shelter.

Some nonnatives are also poisonous. It’s not unusual for cedar waxwings to be poisoned by the fruit of heavenly bamboo (Nandina domestica). And during a recent winter, many wild elk and pronghorn died horrible deaths in Idaho after foraging on Japanese yew (Taxus japonica), which is considered invasive in some states. Hungry bears also have been poisoned in Pennsylvania by English yew (Taxus baccata), and other animals—including livestock and people—can also be poisoned. Instead of nonnative yews, we can plant regional/local yews that wildlife coevolved with. The Pacific Northwest’s yew, Taxus brevifolia, which provides food and cover for many wild species, is the best choice from British Columbia to northern California and east to Montana, at mid to high elevations. Sadly, this attractive understory shrub that grows beneath conifers is in trouble due to over-harvesting for medicine, as well as the logging industry.

Hard work pays off
Research from the Seychelles, an archipelago in the Indian Ocean, shows that sweat and funds invested in eradication can pay off for all sorts of pollinators (bees, butterflies, beetles, birds, reptiles), for the native plants themselves, and for an entire ecosystem. Following the removal of nearly 40,000 invasive shrubs on four mountaintops on one island, researchers monitored the remaining native plants for visits from pollinators. Eight months of observation later, “Ecosystem restoration resulted in a marked increase in pollinator species, visits to flowers and interaction diversity.” Essentially, even during the rather short test period, it was found that both the number of pollinators and their interactions with plants and each other were over 20% higher in the test areas than in control plots (where the invasive shrubs had been left alone). And, the test area native plants also produced more flowers and fruit than those in control areas. Restoration works!


WHAT YOU CAN DO

Eradicate them. Early detection and removal  is crucial to stopping an invasive plant in its tracks, especially if you live near a natural area. To make it feasible, and if you have a variety of invasives, pace yourself—perhaps get rid of one species a week (or one a month or season, depending on the infestation). I strongly recommend forgoing pesticides (even so-called natural ones) and manually digging them out whenever possible. Digging when the soil isn’t saturated is best, to prevent destroying the soil structure that results when working wet soil. And if your arch-enemies grow on a steep slope, be sure to replace them with native erosion controllers (Oregon white oak, madrone, red alder, oceanspray, red-twig dogwood, Nootka rose, kinnikinick, salal, sword fern, etc.—whatever species are local and will do well in the light and soil conditions) as soon as you can; a biodegradable jute netting can be laid down to prevent erosion while new plants fill in.

At the very least, cut stems off at the soil level well before plants go to seed (it can happen quickly!). This method doesn’t disturb the soil (which can invite the germination of more weed seeds and steal moisture) but it can be tedious. Some species can be cut to the soil level and then be covered with a dark cloth like a dark thrift-store bedsheet to block out light (not plastic, which will prevent moisture from reaching the soil and kill soil life). Left for a year or so, it will prevent photosynthesis; afterwards, check to see if you need to dig out any live roots. Persistence usually pays off. In hard to reach places, such as beneath tree or shrub roots, repeatedly cut down or yank out leafy stems—eventually the plant will die from the lack of energy that sunlight provides. The morning glory vines that come from under a dense shrub in my yard get weaker every year because we continually pull out what we see. I seriously think this year may be their last.

One exception to the get-it-out-as-fast-as-you-can rule: If the invasive plants are providing some habitat for wildlife (nesting sites or food or cover), do a soft eviction and take them out gradually or incrementally, after nesting season, rather than all at once. This will avoid completely eliminating the habitat and causing undue stress to wildlife.

Please note: If you need to eradicate English ivy that’s climbing on a tree, cut the vines at the base of the tree but don’t pull it off the bark because bark can be damaged and possibly contribute to a tree’s death.

Herb robert (Geranium robertianum) an invasive plant

Stinky Bob: Pretty, but very assertive in natural areas & gardens.

Remember that some seeds can survive for many years. When I first started gardening in my yard, there were a lot of Robert’s geranium (Geranium robertianum) a.k.a. “Stinky Bob”. I made sure I pulled all the plants before seeds had set, but the next year they were back due to previous years’ seeds. I pulled them again and again, always before they flowered. Fifteen years later, I’m still pulling, but this year there were only two plants! Moral of the story: some seeds can stay viable a very long time, so don’t you dare let up on your weeding. But of course neglected neighboring yards can supply seeds as well, so it’s a continual process. Before planting natives, wait at least a year after the initial removal. Weed again, and then plant. It may not eliminate the seeds, but it should cut down on future seedlings and give the natives the best chance at taking control again. Growing assertive natives, those so-called “pioneer species”  or “early seral” plants generally will be better at competing with weedy non-natives.

Know what you’re planting. Don’t buy newly introduced plants that lack a track record, or seed mixes that may contain invasive seeds, especially ones labeled just “wildflowers.” If you want a wildflower meadow or prairie-style garden, buy only seeds that you know are native to your location and you won’t have to worry. Even though many native “pioneer species” (especially annuals) can be quite assertive, if they spread enthusiastically they won’t wreak havoc on the environment. Species from different regions of the country can be problematic, not just those from Europe or Asia, so go with only your local native plants whenever possible.

Speak up if you notice plants for sale that are problematic.  I’ve seen Arum italicum and Vinca minor and many others for sale at local retail nurseries, even though they’re on my city’s “Nuisance List” (and I’ve seen Stinky Bob, too!).  The thing is, just because plants are deemed invasive or a “nuisance” species, doesn’t mean they can’t be sold—the only plants that are illegal to sell in a particular state are those that have been officially listed as a state noxious weed. But if enough of us educate retailers, hopefully they will pull the plants from their catalog/store.

Besides eliminating invasives in our yards, we need to be very careful about what we’re dragging into natural areas on our hiking boots or sneakers. Plant material like seeds can get stuck in the tread of shoes, and some stick like velcro to laces, like the seeds of the aptly named forget-me-not. And backpacks and pant cuffs can harbor and release seeds, as well as dogs’ paws and fur. When I encountered Stinky Bob in a beautiful natural area last year in the Columbia Gorge; it had already spread over a slope as big as my back yard. No doubt someone unknowingly carried the seed there and the plant that resulted liked it there—a lot.

Tell others about the harm that invasives pose.

Join a local invasive plant eradication effort.

♦ If you see infestations in natural areas report them to the local soil and water conservation district or to an invasives hotline like Oregon’s www.oregoninvasiveshotline.org.

Better choices
Depending on your location and conditions, what are some possible native substitutes for the overzealous travelers, once they’re removed? In the Pacific Northwest, to replace English ivy (and cultivars), consider salal (Gaultheria shallon), kinnikinnick (Arctostaphylos uva-ursi), sword fern (Polystichum munitum), star-flowered false solomon’s seal (Maianthemum stellatum), inside-out flower (Vancouveria hexandra), or Cascade Oregon grape (Mahonia nervosa). Himalayan blackberry might be replaced with thimbleberry (Rubus parviflorus), salmonberry (Rubus spectabilis), or black-cap raspberry (Rubus leucodermis var. leucodermis). Arum could be succeeded by false solomon’s seal (Maiantheum racemosum) or vanilla leaf (Achyls triphylla). Vinca could be ousted by piggyback plant (Tolmiea menziesii), broadpetal strawberry (Frageria virginiana), or oxalis (Oxalis oregana or O. suksdorfii). And Stinky Bob might sublet his space to Western bleeding heart (Dicentra formosa), Oregon geranium (Geranium oreganum), or licorice fern (Polypodium glycyrrhiza). Always research plants’ needs and mature sizes before planting and choose those that would occur naturally in your area.

Herb robert

This huge clump of Geranium robertianum (Stinky Bob)—that’s pushed out native species—probably started with just one seed.

 

© 2017 Eileen M. Stark

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Cultivate Compassion in the Garden (and Beyond)

painted turtles

Whether they’re hidden within fur farms or factory farms or other atrocious places—mistreated and maligned for profit—or in plain sight and struggling within unraveling ecosystems that disappear a little more each day, the suffering of non-human animals due to our expansion and behavior is everywhere. On an ecological level, the most devastating consequence of our ubiquitous presence is the disappearance of wild species that just need to be left alone. They want to live on, and in peace, just as we do. They have just as much right to exist without harm and suffering as we do.

Habitat destruction (including that caused by climate chaos) is not painless and is the main threat to most wild flora and faunas: Less than four percent of original U.S. forests remain; oceans are dying; waterways are heavily polluted with toxins; farmland is quickly expanding; a new study shows that in the past 20 years we’ve managed to destroy a tenth of the earth’s wild areas. Half of North American bird species are predicted to go extinct by the end of this century and some especially sensitive amphibians are already there. We’re the most invasive, destructive, and over-consuming species ever to walk the earth, and it’s costing us the earth, as well as our health and happiness.hermit thrush

Our big brains are burdensome as we thoughtlessly invent things that damage and destroy, but they’re also an asset when we realize our obligation to protect and sustain. Habits of exploitation can be broken. We can stop pretending that everything is fine or beyond our control, and realize that we are very much a part of nature. We don’t have to, for example, conform to having manicured, high maintenance, lawn-dominated landscapes that require massive chemical and fossil fuel applications just because other people have them. We can make choices based on caring what happens to those downstream, just as we wish those upstream would to do to us.

When our species was young, we weren’t separated from nature. Even now, within our bubbles that disconnect, we enter this world not with a fear of natural processes and wild creatures, but with an intense curiosity. But as kids we learn to be fearful—we’re taught to fear the proverbial “big bad wolf,” and trepidation of wildlife and natural processes continue throughout many people’s lives. Education can help change that, and even awaken us to the awe-inspiring, interconnected layers that nature has fashioned over eons of evolution.

Courtesy Predator Defense

Photo courtesy Predator Defense

Just as essential is empathy for other species (that is, looking at their world from their point of view, with compassion). It may be our most important capability and what is sorely needed to bring some balance to the earth’s members. When we allow empathy to guide our choices and practices, we act selflessly and gain empowerment along the way. Changing our ways isn’t always difficult and some changes can be very simple; it just takes some thought and a little motivation. With compassion we can defiantly say “no” to synthetic toxic chemicals crafted by mega corporations that discriminate against other species and seek to control the natural world, “no” to wasteful monoculture lawns, and “no” to merely decorative plants with zero wildlife appeal. We can say “yes” to planning gardens that not only look pretty but also benefit and sustain other species,  “yes” to keeping Fluffy and Fido away from birds and other vulnerable creatures, “yes” to keeping outdoor lights off and making windows visible to birds, and “yes” to initiatives and politicians that seek to preserve and protect natural areas. There are, of course, countless other ways to express compassion for the planet outside the garden.

It’s easy to think that the war against wildlife—from the microorganisms within degraded soil to persecuted predators trying to survive on a human-dominated planet—is happening somewhere “out there.” While a huge percentage of wild lands are dominated by livestock ranching that has “caused more damage than the chainsaw and bulldozer combined,” urban and suburban spaces—including the roughly 40 million acres of land that’s currently lawn—offer an important conservation opportunity and a way for us to personally provide for others right at home.

It’s equally easy to be pulled down by the ticking extinction clock, but once we turn our backs on conventional gardening, we become part of a conversion—or revolution, if you will—that is proactive. Learn how healthy, balanced ecosystems function; watch native plants (especially when grown with others that co-occur in the Native bumblebee on Vancouveria hexandraarea) attract and support a diversity of native insects and other creatures; recognize the  bees and the flower flies and the birds that depend directly or indirectly on those plant communities; discover their life cycle and how to keep them healthy and protected. Plant trees, let the leaves do their thing, allow the dead wood to stay, and forget about pesticides and synthetic fertilizers. If we do all that, we’ll find ourselves more connected and caring even more about what happens within the dwindling, wilder ecosystems on this beautiful planet, and wondering how even more beautiful it will be if more of us empathize with other species.

 

© 2016 Eileen M. Stark

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Gifts of the Oregon White Oak (Quercus garryana) aka Garry Oak

Quercus garryana at Ridgefield NWR


Spring still seems out of reach
, so while we’re awaiting balmier days, let’s take a moment to appreciate some of nature’s subtle, yet generous gifts. We owe everything to the natural world and even modest contact with it refreshes and offers solace. While contemplating the obvious things that nature provides—food, water, clean air—it’s easy to overlook the little (and not so little) things.

Plants, the primary producers on this planet, belong to irreplaceable, intricate, ancient ecosystems, within which they support and depend on other species—both flora and fauna— to survive. I like to think of it as everlasting give and take. This post honors one of my favorite Pacific Northwest natives whose gifts are mammoth. Quercus garryana, commonly called Oregon white oak (or “Garry oak” by those in British Columbia and Washington), is a slow-growing, very long-lived, majestic, deciduous tree that, with time, grows beautifully gnarly. As a keystone species, oak trees are vibrant communities in themselves, and support more life-forms than any other trees in North America.

Wildlife hotspot
Late last fall, while strolling along a trail at Jackson Bottom Wetlands Preserve (just west of Portland), I was awestruck by the amount of life attracted to the broad canopy of just a single mature Oregon white oak: Visible and audible were multiple white-breasted nuthatches, black-capped chickadees, downy woodpeckers, and red-breasted sapsuckers, all busily going about their foraging business with such enthusiasm that all I could do was look upwards, my mouth agape. The birds weren’t seeking the tree’s highly nutritious acorns, which sustain many other birds, as well as insects, mammals, and reptiles—they were consuming a tasty assortment of insect herbivores, which oak trees are particularly adept at generating. Studies show that the genus Quercus hosts more caterpillars and other insect life than any other genus in the northern hemisphere. This proficiency is especially important during breeding season, when the vast majority of landbirds consume and feed their young highly nutritious insects or their larvae, and other arthropods such as spiders—not seeds or fruit. Other studies show a higher diversity of bird species in oak forests than in nearby conifer forests (although pine forests are quite exceptional as well).

Like other native keystone tree species, Oregon white oak peacefully regulates ecosystem processes like nutrient cycling and energy flow, which provides benefits to wildlife (and the rest of us) that seem endless. Besides the obvious shade, beauty, and exchange of oxygen and carbon dioxide that these trees offer (trees really are the best carbon sink), inconspicuous flowers—which typically bloom in late spring—provide for pollinators like native bees, while the buds of forthcoming rounded, deeply lobed leaves play host to the larvae of gray hairstreak, Lorquin’s admiral, echo blue, California sister, and propertius duskywing butterflies. Speaking of leaves, it typically retains dead leaves on its branches until spring, a process known as marcescense. (It’s believed that marcescense, which is more common on young trees, may serve to protect new buds on branches by discouraging browsing animals from grazing. There’s also speculation that marcescent leaves help oaks create a nutrient-rich mulch when the trees need it most —in springtime. But no one knows for sure.)

In addition, cover, perches, and nesting habitat go to birds such as woodpeckers and vireos, as well as native squirrels. Oaks’ acorns sustain squirrels and other mammals, as well as many bird species. Fallen leaves, which might provide habitat for arthropods, amphibians and reptiles, slowly break down into a rich leaf mold that supports soil-dwelling invertebrates and numerous fungi that allow neighboring plants to thrive. Sugars and carbon are provided for mycorrhizal fungi, which reciprocate with nutrients for growing plants and contribute to the soil carbon pool. Intact bark creates microhabitat for mosses, as well as lichens that supply food, shelter, and nesting material, while loose bark and twigs contribute to nest building as well as browse for deer, which in turn feed carnivores like cougars.

And as oaks deteriorate with advanced age (which can be 500 years), they continue to deliver. Dead trees can last many years as snags, which provide food, nesting material, and housing to cavity nesters like owls, kestrels, woodpeckers and chickadees, as well as bats who may roost in old holes or under loose bark.

How it grows
Elevation, climate, soil, and water persuade Oregon white oak to vary immensely in habit and size. While it thrives in cool, coastal areas and near the edges of streams and wetlands where it tolerates seasonal flooding, it also flourishes in droughty inland sites where it may grow both individually and in groves on low hills surrounded by grasslands. When it occurs on gravelly sites or rocky slopes with thin soils, it often has a shrub-like or scrubby habit. Along the blustery Columbia River Gorge, where it grows with little rainfall and atop hundreds of feet of layered basalt, harshly battered trees grow gnarled but hang on thanks to a very extensive and strong root system. As seedlings, this oak’s root mass may be ten times as large as the aboveground growth.

Within the richer, deeper, riparian soils amongst tapestries of dazzling wildflowers and grasses in the Georgia Basin-Puget Trough-Willamette Valley ecoregion of British Columbia, Washington and Oregon, it acts as a keystone structure, typically growing a very broad canopy, and reaching heights 100+ feet over hundreds of years. Gigantic root systems may grow two or three times wider than the canopy. The ecoregion includes savannas (grassland with trees scattered at least 100 feet apart), upland prairies (another type of grassland), wet prairies, and shady oak woodlands with a continuous or semi-open canopy. I’ll call them, collectively, prairie-oak ecosystems.

Endangered ecosystems
To really appreciate an oak, it’s helpful to know something about its unique ecosystems that once provided some of the richest habitat in the world. The historic range of Q. garryana stretches from low elevations of southwestern British Columbia (including Vancouver Island and nearby smaller islands) to California. In Washington, it occurs mainly west of the Cascades on Puget Sound islands and in the Puget Trough, and east along the Columbia River. In Oregon, it is indigenous to the Willamette, Rogue River and Umpqua Valleys, and within the Klamath Mountains.  

When pioneers and naturalists encountered prairie-oak ecosystems, they found a breathtakingly beautiful and rich mosaic of plant and animal life. Journals of early Oregonians described massive prairies with five-mile-wide dense forests of ash, alder, willow, and cottonwood that skirted meandering rivers within floodplains. Marshes and sloughs developed during high water periods but often dried out by late summer. At higher elevations within these forest corridors were oak and associated trees. Above the floodplains were upland prairies, filled with herbaceous plants and grasses that could tolerate the parched soil of summer, as well as winter wet. Oak woodlands stood on low hills above the valley floors, surrounded by grasslands, also known as savanna.

But the landscape was not untouched or pristine. Aboriginal peoples managed parts of the ecosystems following the last glacial period, frequently using prescribed burning to boost edible plant productivity, aid the hunting of wildlife, limit the growth of conifers, and facilitate travel, particularly in the northern parts of the oak’s range. Harvesting of plants such as camas (Camassia spp.) and chocolate lily (Fritillaria affinis) also caused soil disturbance, but their eco-cultural manipulations pale greatly compared to what came later.

Since Euro-American settlement, as much as 99 percent of the original prairie-oak communities that were present in parts of the Pacific Northwest have been lost and many rare species dependent on them are at risk of extinction. Extensive destruction and fragmentation began with settlement in the 1850s, with clearing, plowing, livestock grazing, wildfire suppression, and cutting of trees for firewood and manufacturing. Prairie wetlands bejeweled with wildflowers were drained and ditched. Later, subsidies to ranchers encouraged more destructive grazing, while urban sprawl and agricultural use—fueled by human population increase—intensified. Invasion of nonnative species, and the encroachment of shade tolerant and faster growing species—that proliferate with fire suppression—outcompeted oaks and decimated additional native flora and fauna. Prairie-oak ecosystems and associated systems still continue to disappear at human hands, and isolation of the tiny remaining fragments prevents the migration of wildlife and healthy genetic material from one area to another. Other detrimental factors include diseases and parasites, climate change, and the loss of wildlife that cache acorns and perform other essential functions.  

Conservation
Despite continual destruction, there is a renewed and growing appreciation for the diversity and beauty of these habitats, motivated by recognition that we are responsible for what’s been destroyed, an admiration for the interconnected wild species the habitat supports, and a reverence for an iconic, magnificent tree. Intervention has become intensive, and collaborations and partnerships—along with private landowners, who are key partners—are working to reverse the downward trend with preservation, restoration, and management tools, although “a major restoration challenge is restoring wet prairie habitat to a level at which it can maintain resistance to invasive species,” according to the Institute for Applied Ecology.

Regeneration of oak seedlings is essential, but is often difficult. Acorns look tough, but they are viable for only about a year and may be subject to parasitism, weather extremes, and genetic isolation. Consequently, just a small percentage become trees. Two independent studies determined that oak seedlings do best when caged, but protection from other deterrents—drought, competing plants, and rodents—is important, depending on location.

Regional conservation groups include the Garry Oak Ecosystems Recovery Team and the Cascadia Prairie-Oak Partnership.

Try it at home
While the maintenance of only fragments of a past ecosystem is a poor alternative to former richness, if you live in the ecoregion (or other impoverished oak-dominated ecosystem) and want to help, choose this native tree. Even a single isolated tree can be a critical habitat structure on the landscape. It’s the only oak native to Washington and western Canada, and the dominant one in Oregon (black oak—Quercus kelloggii—is another beautiful and valuable large tree that occurs from Lane County, Oregon, south to Baja, at low to high elevations).

An Oregon white oak tree needs a mostly sunny, well-drained site that can accommodate its eventual size aboveground (25-50 feet wide, depending on spacing) and enormous root systems described above. Those grown on poor, dry, rocky sites will grow quite a bit smaller and have a shrubby habit. When planting more than one, space trees 20 to 60 feet apart, using the closest spacing only in dry, rocky terrain. It may be most helpful to visit a nearby natural area and then try to mimic nature’s arrangement.

To maintain genetic integrity, always choose trees or seeds that originated from trees close to your location and from similar terrain. For best results, plant dormant saplings in late fall after rains begin. After watering, apply about three inches of an organic mulch to reduce evaporation and keep weeds (that can steal water and nutrients) down. I prefer low-nitrogen leaf compost, spread out to the tree’s drip line and kept at least a foot from the trunk to prevent rot. Oaks do not need rich soil, so don’t apply synthetic or organic fertilizer because most North American trees don’t need fertilizer and may even respond adversely to it. And don’t use those watering bags that only water at the base of the trunk and may promote rot

Though this species is drought tolerant, provide ample summer water, deeply and infrequently until established. During the first summer I like to water roughly every five days with about 10 gallons of water that’s applied so that it sinks in slowly. During the second and third summers, water once a week, 10-15 gallons, being sure to water out to the root zone (drip line) and beyond—root spread can be more than twice that of the crown. If severe heat and prolonged droughts appear to be stressing a young tree, provide more water. After the first few years it may do fine on its own, but do water it (deeply) if it appears to be drought stressed. Keep the area well weeded and don’t stake trees unless they are in very windy areas—they’ll grow much stronger if left unsupported. Keep in mind that soil compaction, hardscape, lawns and irrigation systems around water-sensitive oaks are a major cause of their decline in residential areasHere is more info on how to plant Oregon white oak.

Grab a partner
As with other native species, oaks will function best when grown within a habitat and community type that consists of plants that evolved together and need the same conditions. Figuring out which community occurs in your area requires a walk in a nearby natural area where species, as well as nature’s organization, can be learned. Some associate trees that might thrive with your oak include Oregon ash (Fraxinus latifolia) on moist sites, and madrone (Arbutus menziesii) on drier sites, and Pacific ponderosa pine (Pinus ponderosa subsp. Benthamiana). For shrubs, consider california hazelnut (Corylus cornuta var. californica), osoberry (Oemleria Aquilegia formosacerasiformis), serviceberry (Amelanchier alnifolia), snowberry (Symphoricarpos albus), oceanspray (Holodiscus discolor), red-twig dogwood (Cornus sericea), and tall Oregon grape (Mahonia aquifolium), depending on your location. Sword ferns (Polystichum munitum), orange or pink honeysuckle (Lonicera ciliosa or L. hispidula), fescues (Festuca spp.), and many wildflowers, including allium (Allium cernuum), camas (Camassia spp.), meadow checker mallow (Sidalcea campestris), western columbine (Aquilegia formosa, pictured right), and shooting star (Dodecathon spp.) associate in different parts of its range.

To find out which habitat type and plant communities would likely have grown in your area, check out this Ecoregional Assessment, or query your county’s soil and water conservation district or native plant society chapter. The following publications may also be helpful:
~ Georgia Basin: Garry Oak Ecosystems Recovery Team
~ Puget Trough: Prairie Landowner Guide for Western Washington 
~ Willamette Valley: A Landowner’s Guide for Restoring and Managing Oregon White Oak Habitats

 

© 2017 Eileen M. Stark

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One Hundred Years: John Muir’s Legacy Lives On

Multnomah Creek, Oregon

Several days ago I intended to post a fairly comprehensive tribute to the “Apostle of the Wild,” John Muir, who died a century ago on Christmas Eve, but a cold got the better of me. Muir was enthralled with the earth and I count his writings among those that stirred my passion for nature; he was one of the great thinkers who made a prominent impression on countless others.

A Scottish immigrant, Muir studied natural sciences at the University of Wisconsin but became a naturalist, conservationist, geologist, botanist, philosopher, poet, and eventually a public figure, through what he called the “University of Wilderness” (although many actual universities, including Harvard and Yale, later granted him honorary degrees). His writings “belonged to that tradition of British naturalists whose work was so fused with the writer’s personality and so penetrated by individual feeling that their output was as much literature as science,” opined the L.A. Times the day after his death in 1914. Muir dedicated his life to the preservation of wilderness areas and national parks.

Tragically, Muir’s legacy is under attack. But in “John Muir’s Last Stand,” Tom Butler and Eileen Crist celebrate the man and the gifts he left us, while defending a wilderness movement that protects the wild, for its own sake. I could not have said it better.

 

© 2014 Eileen M. Stark

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