Eileen M. Stark's Blog, page 9

Fragrance in a Northwest Garden

Had Carl Sandburg penned a poem about the way a captivating scent wafts through the air (prior to his famous “Fog”), he might have written that it approaches us “on little cat feet.” Scent is also silent, but invisible, and adds a fresh, sensual dimension to a garden (or a walk in the woods for that matter). One of the most fragrant flowering shrubs is mock orange, and the Pacific Northwest’s native offering, Philadelphus lewisii (Western or Lewis’ mock orange), doesn’t disappoint.

It’s named after scientist and explorer Meriwether Lewis, who collected it in 1806 during the Lewis and Clark expedition. Native Americans had numerous uses for it, including making tools, snowshoes, furniture, and even soap. Plan ahead and place this medium-sized deciduous shrub where its fragrance can be noticed.

How they grow

Although there is quite a bit of individual variation within this species, its structure and growth pattern goes something like this: Maturing at 5 to 10 feet tall and nearly as wide, this fairly fast-growing shrub may send out arching basal shoots as it ages. In late spring, flowering shoots appear, followed by vegetative growth. Rich green, egg-shaped leaves (roughly three inches long) grow in pairs along its stems. At the tips of branches, multiple clusters of white, four-petalled blossoms adorned with soft yellow stamens emerge in late spring or early summer, sparkling against the leafy green backdrop. Flowers measure one to two inches in diameter, and offer a lovely, fruity fragrance.

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

Try it at home

Mock orange is easy to grow. It tolerates both drought (after it’s established, of course) and moisture, and will do well in full to part sun or in a fair amount of shade (but not deep, dark shade). It’s a good shrub for stabilizing soil on slopes. While not fussy about soil, incorporating some organic matter (like compost) will get it off to a good start.

 

Grab a partner

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

Other fragrant PNW plants include wallflower (Erysimum capitatum), Nootka rose (Rosa nutkana), Oregon grape (Mahonia aquifolium), oceanspray (Holodiscus discolor), and black hawthorn (Crataegus douglasii). Enjoy!

 

© 2016 Eileen M. Stark

To leave a comment, click on post’s title

Be a Voice for Portland’s Trees!

Portland is losing a great many valuable trees due to rampant development. After much public outrage and several committee and commission meetings/hearings later, Portland City Council will at last address the issue (temporarily) on Thursday, March 3, 2016 (for more background info, please see this post.)

Over the past couple of months, staff from the Bureau of Parks and Recreation and from the Bureau of Development Services developed proposals intended as tree preservation “stop-gap” measures until Portland’s full tree code (Title 11) can be fully examined and reformed. Their proposals were then considered by the Planning and Sustainability Commission (PSC) and the Urban Forestry Commission (UFC). Subsequently, the PSC and the UFC each made separate recommendations to City Council. The initial staff proposals, the recommendations by the PSC and the UFC, and a table comparing those proposals and recommendations are available here.  Most recently, Commissioners Amanda Fritz and Dan Saltzman put together their own proposal (Fritz/Saltzman Proposal). Unfortunately, it’s possible that the council members will consider passing the Fritz/Saltzman proposal as is, even though it contains a number of weaknesses, which I’ve outlined below.

Please attend the March 3 City Council meeting at 2 PM (Council Chambers at City Hall, 1221 SW 4th Ave). If that’s not possible, please email your comments (before March 3) to CCTestimony@portlandoregon.gov (or mail to 1221 SW 4th Ave., Room 130, Portland 97204). It’s best to put the following talking points into your own words.

♦ Portland’s urban forest is dwindling, with large, valuable trees being replaced by species (mostly nonnative) that are small in form and benefits. There are very few huge trees in the city, and it’s important to note that many species (even highly beneficial native ones) do not grow to a large diameter (or they are extremely slow-growing, as in the case of Oregon white oak). Removing young trees will eventually result in a lack of mature trees that are so aesthetically and ecologically appealing. The Urban Forestry Commission’s recommendations state that “… roughly no more than 2% of trees currently standing in Portland would benefit from [the Parks or BDS proposals]. The PSC proposal would affect ~4% of all trees currently being permitted for removal as tallied by BDS in August 2015.”

♦ Mitigation is not preservation—it merely applies a disincentive to remove trees; it does not protect them. For those with enough money, it’s simply an annoyance. To be most effective, mitigation should be based on size, but also species, via inch-for-inch replacement (minimum $300 per inch) for trees 20 inches or greater (with no cap on total fee). For smaller trees, update the outdated fee-in-lieu of preservation fee with Urban Forestry’s current costs of planting a tree and providing it with 3 years of care.

♦ The threshold for very large trees should be no more than 30 inches DBH. 

♦ Amendments should apply to lots less than 5,000 sq. ft., since valuable trees certainly do exist on small lots. The UFC considers it “a significant loophole that is likely to allow significant unregulated and unmitigated removal of significant trees during development … [and] recommends that these provisions apply to lots 3,000 sq. ft. and larger.”

♦ Amendments should apply to trees on private property, but also street trees and trees on city, commercial, and industrial land. Wildlife in need of trees to survive doesn’t care what type of land trees live on!

♦ At least 30 days notice should be given to neighbors and neighborhood associations. Further, Type II reviews should be implemented whenever there are plans to destroy significant trees.

♦ Amendments should only be temporary and be in effect for no more than 3 years.

♦ A complete and comprehensive overhaul of Title 11 is essential following implementation of a temporary stop-gap measure. It should be funded and undertaken ASAP.

© 2016 Eileen M. Stark

To leave a comment, click on post’s title

Gifts of the Oregon White Oak (Garry oak)

 

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, air—it’s easy to overlook the little (and not so little) things.

Plants, the primary producers on this fragile planet, belong to entwined, interconnected 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.

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 acorns, which sustain many other birds, as well as mammals—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 spiders—not seeds or fruit. Other studies show a higher diversity of bird species in oak forests than in nearby conifer forests.

Like other dominant native tree species, Oregon white oak placidly regulates ecosystem processes like nutrient cycling and energy flow. And its benefits to wildlife (and the rest of us) seem endless: 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 the gray hairstreak, California sister, and propertius duskywing butterflies. Fallen oak leaves, which can provide habitat for amphibians and reptiles, slowly break down into a rich, particularly nutritious leaf mold that supports soil-dwelling invertebrates and numerous fungi. Intact bark creates microhabitat for lichens and mosses, while loose bark and twigs contribute to nest building as well as browse for deer, which in turn feed carnivores like cougars. Cover, perching, and nesting habitat go to birds such as woodpeckers and vireos, as well as native squirrels. Shade, beauty, and participation in the earth’s exchange of oxygen and carbon dioxide are freely given to everyone. Even 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 shelter to cavity nesters like owls, kestrels, 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 in habit and size. It thrives in cool, damp coastal areas and near the edge of streams and wetlands where it tolerates seasonal flooding and mixes with Oregon ash (Fraxinus latifolia). But 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. But when growing in the richer, deeper, riparian soils amongst tapestries of dazzling wildflowers and grasses in the Willamette Valley-Puget Trough-Georgia Basin ecoregion of Oregon, Washington, and British Columbia, it typically grows a very broad canopy, and to a height of as much as 100 feet. The ecoregion includes savannas (grassland with scattered trees), 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 further appreciate Oregon white oak, it’s helpful to know something about its unique and highly endangered ecosystems that once provided some of the richest habitat in the world. The historic range of Quercus garryana stretches from low elevations of southwestern British Columbia (including Vancouver Island and nearby smaller islands) into southern California. In Washington, it occurs mainly west of the Cascades on Puget Sound islands and in the Puget Trough, as well as in the southwestern part of the state, and east along the Columbia River. In Oregon, it’s 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.

Today, very little of these ecosystems remain and many species are at risk of extinction. Destruction and fragmentation of the landscape began with European settlement in the 1850s, with clearing, plowing, and livestock grazing, fire 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, invasive species, climate change, and the encroachment of shade tolerant and faster growing species—that proliferate with fire suppression—outcompeted oaks and displaced additional native flora and fauna. Sadly, the historic composition and function of these diverse ecosystems—and associated ones—continues to disappear at human hands; less than ten percent of pre-European prairie-oak ecosystems remains in the ecoregion; in B.C. studies indicate that the loss is greater than 95 percent. According to the BLM, less than one percent of Oregon’s oak-dominated habitats are protected in parks or preserves, and most of the original prairie-oak ecosystems in Oregon are now dense forests. Isolation of the few fragmented oak community remnants prevents the migration of populations and of healthy genetic material from one area to another.

Conservation

Fortunately, there is a renewed and growing appreciation for the diversity and beauty of these habitats, motivated by our recognition that we are responsible for what we’ve destroyed, an admiration for the wild species they support, and a reverence for an iconic, magnificent tree. Non-profit land trusts and private landowners are working to protect, manage, and reverse the trend of prairie-oak ecosystem loss, 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. Nearby “associated ecosystems,” such as seasonal wetlands and coastal bluffs—which typically share many of the biological and ecological features, as well as species of prairie-oak ecosystems—also must be protected due to the same threats and vulnerabilities.

Try it at home

If you live in the ecoregion mentioned above and want to help this impoverished ecosystem, choose this native tree. 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).

You’ll need a sunny, well-drained site that can accommodate the tree’s eventual size (40—80 feet tall x 30-50 feet wide in garden situations), although when grown on poor, dry, rocky sites it will grow quite a bit smaller and will have a shrubby habit. When planting more than one, space them 20 to 60 feet apart, using the closest spacing only in dry, rocky terrain. But don’t be daunted by this tree’s mature size—it grows at a snail’s pace!

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. Apply about 3 inches of an organic mulch (after watering) to reduce evaporation and keep weeds (that can steal water and nutrients) down. I prefer leaf compost, spread out to the tree’s drip line and kept at least 3 inches from the trunk to prevent rot.

Though this species is drought tolerant, provide ample summer water, deeply and infrequently, until established (2-5 years). During the first year I like to water roughly every 5 days with about 10 gallons of water that’s applied so that it sinks in slowly and doesn’t run off. During the second and third summers, water once a week, 10-15 gallons, being sure to water out to the root zone and a little beyond. If severe heat and prolonged droughts appear to be stressing a young tree, provide more—you don’t want to stunt its growth. 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. Here is more info on how to plant Oregon white oak.

Grab a partner

Remember that, like other native species, your oak tree will function best with companionship from other plants that evolved alongside it, and, aesthetically speaking, they will look like they were meant for each other (but keep new plantings at least several feet away). Some associate trees that will thrive with your oak include Oregon ash (Fraxinus latifolia) on moist sites, and madrone (Arbutus menziesii) and ponderosa pine (Pinus ponderosa) on drier sites. For shrubs, consider california hazelnut (Corylus cornuta var. californica), Indian plum (Oemleria cerasiformis), 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), and shooting star (Dodecathon hendersonii) 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 try your local soil and water conservation district or native plant society chapter. Also consult the following publications, depending on your location:

~ Georgia Basin: Garry Oak Ecosystems Recovery Team

~ Willamette Valley: A Landowner’s Guide for Restoring and Managing Oregon White Oak Habitats

~ Puget Trough: Landowner guidebooks for South Puget Sound Prairies

 

© 2016 Eileen M. Stark

To leave a comment, click on post’s title

Gifts of the Oregon White Oak

 

Spring still seems out of reach, so while we’re waiting for 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. When contemplating the obvious things that nature provides—food, water, air—it’s easy to overlook the little (and not so little) things.

Plants, the primary producers on this fragile planet, belong to entwined, interconnected 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 size and 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.

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 acorns, which sustain many other birds, as well as mammals—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, larvae, and spiders (not seeds or fruit). Other studies show a higher diversity of bird species in oak forests than in nearby conifer forests.

Like other dominant native tree species, Oregon white oak placidly regulates ecosystem processes like nutrient cycling and energy flow. And its benefits to wildlife (and the rest of us) seems endless: 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 the gray hairstreak, California sister, and propertius duskywing butterflies. Fallen oak leaves, which provide habitat for amphibians and reptiles, slowly break down into a rich, particularly nutritious leaf mold that supports soil-dwelling invertebrates and numerous fungi. Bark creates microhabitat for lichens and mosses, while twigs and loose bark contribute to nest building as well as browse for deer, which in turn feed carnivores like cougars. Cover, perching and nesting habitat go to birds such as woodpeckers and vireos, as well as native squirrels. Shade, beauty, and participation in the earth’s exchange of oxygen and carbon dioxide are freely given to everyone. Even as oaks deteriorate with advanced age (which can be 500 years), they continue to deliver. Dead trees can last many years as snags that provide shelter to cavity nesters like owls, kestrels 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 in habit and size. It thrives in cool, damp coastal areas and near the edge of streams and wetlands where it grows near Oregon ash and tolerates seasonal flooding. But it also commonly flourishes in droughty inland sites where it grows 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. But when growing in the richer, deeper, riparian soils amongst tapestries of dazzling wildflowers and grasses in the Willamette Valley-Puget Trough-Georgia Basin ecoregion of Oregon, Washington, and British Columbia, it typically grows a very broad canopy, and to a height of as much as 100 feet. The ecoregion includes savannas (grassland with scattered trees), 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 further appreciate Oregon white oak, it’s helpful to know something about its unique and highly endangered ecosystems that once provided some of the richest habitat in the world. The historic range of Quercus garryana stretches from low elevations of southwestern British Columbia (including Vancouver Island and nearby smaller islands) into southern California. In Washington, it occurs mainly west of the Cascades on Puget Sound islands and in the Puget Trough, as well as in the southwestern part of the state, and east along the Columbia River. In Oregon, it’s indigenous to the Willamette, Rogue River and Umpqua Valleys, and in 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 the higher elevations within the 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.

Today, very little of these ecosystems remain and many species are at risk of extinction. Destruction and fragmentation of the landscape began with European settlement in the 1850s, with clearing, plowing, and livestock grazing, fire 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, invasive species, climate change, and the encroachment of shade tolerant and faster growing species—that proliferate with fire suppression—outcompeted oaks and displaced additional native flora and fauna. Sadly, the historic composition and function of these diverse ecosystems—and associated ones—continues to disappear at human hands; less than ten percent of pre-European prairie-oak ecosystems remains in the ecoregion; in B.C. studies indicate that the loss is greater than 95 percent. According to the BLM, less than one percent of Oregon’s oak-dominated habitats are protected in parks or preserves, and most of the original prairie-oak ecosystems in Oregon are now dense forests. Isolation of the few fragmented oak community remnants prevents the migration of populations and of healthy genetic material from one area to another.

Conservation

Fortunately, there is a renewed and growing appreciation for the diversity and beauty of these habitats, motivated by our recognition that we are responsible for what we’ve destroyed, admiration for the wild species they support, and reverence for an iconic, magnificent tree. Non-profit land trusts and private landowners are working to protect, manage, and reverse the trend of prairie-oak ecosystem loss, 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. Nearby “associated ecosystems,” such as seasonal wetlands and coastal bluffs—which typically share many of the biological and ecological features, as well as species of prairie-oak ecosystems—also must be protected due to the same threats and vulnerabilities.

Try it at home

If you live in the ecoregion mentioned above and want to help an impoverished ecosystem, choose this native tree. 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).

You’ll need a sunny, well-drained site that can accommodate the tree’s eventual size (40—80 feet tall x 30-50 feet wide in garden situations), although when grown on poor, dry, rocky sites it will grow quite a bit smaller and will have a shrubby habit. When planting more than one, space them 20 to 60 feet apart, using the closest spacing only in dry, rocky terrain.

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. Apply about 3 inches of an organic mulch (after watering) to reduce evaporation and keep weeds (that can steal water and nutrients) down. I prefer leaf compost, spread out to the tree’s drip line and kept at least 3 inches from the trunk to prevent rot.

Though this species is drought tolerant, provide ample summer water, deeply and infrequently, until established (2-5 years). During the first year I like to water roughly every 5 days with about 10 gallons of water that’s applied so that it sinks in slowly and doesn’t run off. The second and third years water once a week, 10-15 gallons, being sure to water out to the root zone and a little beyond. If severe heat and prolonged droughts appear to be stressing a young tree, provide more—you don’t want to stunt its growth. 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. Here is more info on how to plant Oregon white oak.

Grab a partner

Remember that. like other native species, your oak tree will function best with companionship from other plants that evolved alongside it, and, aesthetically speaking, they will look like they were meant for each other (but keep new plantings at least several feet away). Some associate trees that will thrive with your oak include Oregon ash (Fraxinus latifolia) on moist sites, and madrone (Arbutus menziesii) and ponderosa pine (Pinus ponderosa) on drier sites. For shrubs, consider california hazelnut (Corylus cornuta var. californica), Indian plum (Oemleria cerasiformis), 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), and shooting star (Dodecathon hendersonii) 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 try your local soil and water conservation district or native plant society chapter. Also consult the following publications, depending on your location:

~ Georgia Basin: Garry Oak Ecosystems Recovery Team

~ Willamette Valley: A Landowner’s Guide for Restoring and Managing Oregon White Oak Habitats

~ Puget Trough: Landowner guidebooks for South Puget Sound Prairies

 

© 2016 Eileen M. Stark

To leave a comment, click on post’s title

Improve Portland’s Tree Code to Save Important Trees

 

Portland is generally a pretty progressive city, and that’s one of the reasons that many of us choose to live here. Another reason is its natural beauty, much of which is supplied by trees. But today, no tree—even if it’s huge, healthy, native, and majestic—is safe anywhere in the city due to currently out-of-control development rules that favor developers and their bottom line.

Portland’s relatively new tree code (Title 11) has proved to be inadequate in that it currently does not require that any tree in a development situation be preserved. The code currently allows for the removal of 2/3 of a property’s trees, with just 1/3 retained. However, for a measly $1200 (maximum) “fee in lieu of preservation” per tree, a developer can destroy the third if they’re in his way, no questions asked. Moreover, properties less than 5,000 square feet (your average 50 x 100-foot lot) and commercial/industrial zones are completely exempt from the code.

According to city records, tree removal permits for demolition and new construction during one month—August 2015—revealed that only 13 of 53 trees that were greater than 24 inches DBH (trunk diameter at breast height) were spared the chainsaw. Several of the trees destroyed during that month were greater than 42 inches DBH. Granted, one month is a small sample and not an average, but the point is that we cannot afford to lose any more quality trees. Comments during a recent Oversight and Advisory Committee (OAC) meeting revealed that Portland’s tree canopy is likely shrinking.

Speak up for voiceless trees and wildlife!

Two proposals—one from Urban Forestry’s office and one from the Bureau of Development Services­—will be reviewed by the Planning and Sustainability Commission (January 12) and by the Urban Forestry Commission (January 21). Both proposals seek protections only for trees greater than 48 or 50 inches DBH and they are lax in other ways. (The January 12 meeting

begins at 12:30 pm and testimony will likely start at 2 pm) 

Trees over 48 inches DBH are very rare in Portland. For example, in Wilshire Park, which is home to 346 trees (most of them mature Douglas-firs), we found that only two measured 48 inches DBH or just slightly greater. Under either proposal and if these trees were in development situations, only two trees of the 346 trees would be safe.

Large, mature trees are extremely important to wildlife for food and shelter, and they provide myriad other environmental benefits and as such ought to be protected. But we also need to recognize that we will have much fewer large trees in the future if developers are allowed to remove any tree that’s in their way now.

Follow the Plan

The 2035 Portland Comprehensive Plan clearly states, “potential adverse impacts of development must be well understood and avoided where practicable. These policies also call for an evaluation of design alternatives to minimize negative impacts, and the use of mitigation approaches that fully mitigate unavoidable impacts.” It also recommends preserving Pacific Northwest native

trees.

Title 11 does not provide incentive to keep trees, nor does it require consideration of design alternatives. A paltry mitigation fee cannot fully mitigate the loss of ecologically and aesthetically

significant trees that are part of our neighborhoods and region, and whose loss permanently impacts people and devastates wildlife. We must first seek to avoid, then minimize, and then, and only as a last resort, mitigate.

Mitigation as a last resort

When healthy, mature, life-giving trees are eliminated, it’s impossible to replicate their benefits. How can we possibly compensate for the sudden loss of something irreplaceable? What happens to exhausted migratory birds that counted on a certain trees as stopover habitat? Planting a few sapling trees cannot supply the lost cover and food for wildlife any more than they can supply the shade, oxygen, and carbon sequestration provided by a mature tree. The graph at the end of the OAC’s recommendations shows how terribly long it takes for young replacement trees to begin to supply benefits (and some never will). Plus, the replacements are often smaller species and/or planted off site, possibly miles away, so the benefit to local wildlife is nonexistent.

All trees are not created equal

Preserving the towering, big-canopy trees that supply the most environmental and public health benefits like cleaner air and water makes perfect sense, but we also need to look at species as well as diameter. While large trees—especially conifers—are immensely important for wildlife, shade, and storm water mitigation, studies have concluded that certain tree types are enormously supportive of native insect herbivores, which provide essential food for wild species like birds.

But many valuable native trees do not grow large. In fact, some only grow to 20 inches DBH at maturity, at most. And others are so slow growing that even at age 50 they would not have the girth that would be considered “large.” Native oaks support the most insect herbivores (over 540 species of butterfly and moth, alone), but oaks—especially our beloved Oregon white oak (Quercus garryana)—are very slow growers and to reach 30 inches DBH could take well over 100 years, depending on conditions. Native wild cherries (genus Prunus), willows (genus Salix), birch (genus Betula), aspens/cottonwood (genus Populus), and pines (Pinus spp.) are other highly productive species for insect herbivores that in turn support other wildlife. With the exception of ponderosa pine and cottonwood, all of the faster growing trees mentioned do not grow to a large diameter.

We also need to consider the repercussions of removing trees that were, for example, preventing erosion on hillsides, providing a windbreak, or protecting nearby vegetation.

What do other progressive cities do?

Some cities have adopted regulations that could serve as a model for Portland. Vancouver, B.C. requires that all new houses be built on existing footprints; they do not allow a modest house to be replaced with a 3,000 or 4,000 square foot home that no one needs and does not contribute to urban density. Lake Oswego requires that “Removal of the tree will not have a significant negative impact on erosion, soil stability, flow of surface waters, protection of adjacent trees, or existing windbreaks” and “Removal of the tree will not have a significant negative impact on the character, aesthetics, or property values of the neighborhood. The City may grant an exception to this criterion when alternatives to the tree removal have been considered and no reasonable alternative exists to allow the property to be used as permitted in the zone. In making this determination, the City may consider alternative site plans or placement of structures or alternate landscaping designs that would lessen the impact on trees, so long as the alternatives continue to comply with other provisions of the Lake Oswego Code.”

How you can help

If you believe that Title 11’s lack of protection for trees and its wholly inadequate mitigation provisions need to be changed, I encourage you to offer comments or simply show your support at either of the above mentioned meetings. I attended and testified at several of the OAC meetings this past fall and I can tell you that they do listen and consider sensible comments. My suggestion that the value of small and/or slow-growing native trees be considered in their recommendations did make it into their memorandum.

If you can’t make the meetings you may send written comments (with your name and address) via email to: PSC@PortlandOregon.gov and trees@PortlandOregon.gov

Suggested comments:

♦ Remove the Title 11 exemptions for small lots and commercial and industrial land

♦ Avoid destruction by requiring design alternatives to cutting

♦ Require a site review process with public involvement for trees greater than 20 inches DBH.

♦ Require mandatory posting/public notice and at least a 30-day period before any tree greater than 20 inches DBH is cut down

♦ Consider tree species, giving special consideration to the superior ecological value of Willamette Valley native trees, no matter their size

♦ Use mitigation as a last resort, adding an inch-for-inch protocol, at least $300 per inch for healthy trees greater than 20 inches DBH, and $500 per inch for native species, and changing the 1/3 preservation rule to preservation of caliper inches of trees on site.

© 2016 Eileen M. Stark

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Killer Windows: How to Help Stop Bird Collisions

          When I read a recent post from my local wildlife rehab center announcing that they’ve been caring for 4 varied thrushes in their facility—all injured by window collisions—it got me thinking. This winter I’ve seen just one of these gorgeous birds in our yard. Might the others have been victims of window collisions? I certainly hope not, but the rehab center reportedly takes in several hundred window victims each year, and it’s not hard to imagine that countless others die out of sight. Certain species, including thrushes, cedar waxwings, warblers and woodpeckers, are more likely to fly into reflective glass, and migratory species are also at high risk. Studies conclude that the more glass on a structure, the greater the chance of mortality, and windows that reflect vegetation create more risk.

A billion deaths a year

Contrary to popular belief, it’s not unusual for birds to collide with windows. In fact, ornithologists say that bird fatality by collision with manmade structures is second only to habitat loss that’s brought on by agriculture, industrial forestry, urban development, invasive species, and climate change. The number of deaths due to window strikes is appalling: It’s estimated that as many as one billion birds die each year from encounters with reflective surfaces in North America! While large, commercial buildings may pose the most danger, any unobstructed, reflective window can kill. Birds that don’t die quickly from injury may suffer slow deaths or become easy prey for predators. Many bird species, such as the elusive varied thrush, are already in steep decline and deaths by collision only exacerbate the problem.

What they see

Birds don’t see window glass and shiny or mirrored office buildings like we do. They see a reflection of trees, shrubs, and sky that appears to be a clear path, and consequently fly into it. Moreover, some fruit-eating species may get intoxicated by eating fermented berries and are more likely to hit windows while flying drunk.

Or, birds may see through clear glass (such as two corner windows, a solarium, or a bus shelter) and are deceived into flying right through as they try to get to vegetative cover that they see beyond the glass. Reportedly, this can also happen if indoor plants are situated right next to windows.

Some species, such as robins and bushtits, see their reflection during breeding season, view it as an intruder to their territory, and actually attack the glass—I’ve seen it happen. This territorial behavior can be intense, but they usually aren’t seriously injured (unlike the other situations). It can also happen at car windows.

How you can help

Because windows are everywhere, it’s easy to think that the problem is too overwhelming to do anything about. But any bird-friendly change you make to your property’s windows can help. Especially if your good intentions attract birds to your yard—with feeders and/or native plants—or you’ve noticed birds hitting your windows, it ought to be compulsory.

Bird strikes often follow a pattern, with the same windows repeatedly struck. If you have a lot of windows, take some time to identify which windows are problematic, paying attention to bird attractants like food, water, and cover. Look at your windows from a bird’s point of view. 

Most of the following remedies work either by blocking glass or making it visible to birds by giving them visual cues. Sheer curtains and blinds closed part way may help cut down on reflection, but they don’t fully eliminate it. Silhouettes placed on the inside of windows do not work because birds still see the reflection.

DIY suggestions:



◊  Locate all bird feeders or birdbaths at least 30 feet from windows, a distance that allows birds to see that windows are part of a house. Or, keep them very close—within 2 feet—to reduce the chance of high impact collisions. If that doesn’t help, either add additional protections or remove the feeders altogether.

◊  If any of your windows have a clear view through your house to another window, create an obstruction that blocks what may appear to be a flight path.

◊  Keep taut window screens on year round if you have them. Keeping your windows dirty may also help!

◊  Make your own “zen wind curtains,” which are practical and effective.

◊  Apply patterns (a few inches apart) with soap on the outside of windows—use stencils found at craft stores, or make your own. The patterns can be wiped off and redone when necessary.

◊  For birds who fight with their reflection, simply hang a cloth or apply some masking tape to the area for a few days to break the bird of the habit.

Products you can purchase:

◊  Decals that reflect ultra-violet wavelengths of light—which birds can see but we can’t—are applied to the outside of windows. Follow manufacturers instructions for adequate coverage (aim for 80%), generally a couple of inches apart. Some examples include Window Alert (pictured) and BirdTape,  which provide a stoplight for birds. In direct sunlight, decals will need to be replaced more often than in shade, so be sure to keep track of when you put them up. If you have a lot of windows to cover, BirdTape is more economical and may last longer. 

◊  Films like CollidEscape, that appear opaque to birds but transparent to you, are applied to the outside of windows.

◊  External awnings or sun shades help minimize both reflection and transparency.

Architectural solutions:

Planning on remodeling or building a new home? Are you an architect or developer? The Resource Guide for Bird-Friendly Building Design is a comprehensive publication that offers excellent info and workable solutions for reducing collisions in commercial areas as well as residential.

Other recommendations:

At night, turn off lights in office buildings (all levels), especially during spring and fall migrations. At home, pull your shades or draw draperies, and install motion censors rather than leaving outdoor lights on at night. This prevents disorientation of migratory birds travelling at night.

If you find a bird on the ground near a window: Slowly and gently cover and catch the bird with a lightweight, soft cloth and carefully place it in a small box (such as a shoebox) that has air holes and is lined with a soft cloth or paper towels rolled into a doughnut shape to keep the bird upright. Handle the bird as little as possible and keep the box securely closed. Do not give food or water. Place the box in a quiet, dark, and warm (but not hot!) place, away from other animals and children. If the bird has an obvious injury like a cracked bill or dangling wing, transport it immediately (in the darkened box ) to a licensed wildlife rehabilitator—broken bones need attention quickly. If there are no obvious injuries, quietly check on the bird two or three times over an hour—outside and away from human activity and buildings in case the bird can fly—but don’t touch it. If the bird develops swollen eyes or becomes unresponsive during the hour, quickly transport it to a wildlife rehabilitator. If the bird seems alert and can stand on its own, place the container in a quiet spot and open it. Remain still and out of sight and wait. If s/he doesn’t fly away, carefully and quietly take the bird to a wildlife rehabilitator. Remember that, other than transporting a bird to a rehabilitator, it is illegal to handle migratory birds without a license.

 

© 2015 Eileen M. Stark

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Manage Stormwater at Home for Clean Rivers and Habitat

It’s another one of those exceptionally rainy days (with more to follow) and I don’t want to do laundry or even take a bath. Why? A few days ago the city’s sewers overflowed into the river, and I’d rather not add more water to an already overtaxed system that results in raw sewage killing and polluting the habitat of wild species downstream. It’s not just the abundance of rain that’s the problem: It’s our infrastructure.

Generally, the unaltered earth is perfectly capable of soaking up or directing the moisture that nature doles out to natural waterways or floodplains (seasonal flooding is normal and natural). But our urban and suburban environments, with their ubiquitous and impermeable roads, walkways, roofs, and parking lots—as well as shortage of erosion-controlling plants—cause runoff that carries toxic pollutants like oil, fertilizers, and pesticides during heavy rains.

In older parts of cities, pipes and tunnels that take away domestic and industrial waste combine with water collected from surface runoff. Under normal (not too wet) circumstances, the sewage and runoff is diverted to sewage treatment plants. But when too much storm water or snowmelt can’t soak in, it overwhelms the system, creating combined sewage overflows (CSOs) that cause raw sewage and other pollutants to spill into rivers, lakes, and coastal waters. People may be told not to have contact with the water, but wildlife suffers silently. Essentially, polluted sediments build up in the water, increasing water temperature and turbidity, and lowering oxygen levels, resulting in deaths.

In Portland, where I live, the city is investing in stormwater management projects that (sort of) mimic nature, in an attempt to mitigate stormwater at its sources. There is a plethora of work going on and CSOs are reportedly decreasing in frequency, but even one is too many.

How to help keep water clean

We can help manage and reduce stormwater pollution and overflows, starting at home. Here are some tips; some will have immediate effect, while others will take some time and effort:

◊ Protect existing conifer trees and plant new ones (preferably those that historically grew in your area). A mature evergreen tree can intercept more than 4,000 gallons of rainwater each year, about 80 percent more than deciduous trees. They also provide habitat, beauty, shade and cooling and help stabilize soil.

◊ Renovate or construct new walkways, driveways, and patios with interlocking stones or other permeable paving, rather than concrete.

◊ Disconnect your home’s downspouts when feasible and install rain gardens or swales in landscaped areas. They help prevent flooding by allowing water that falls on your roof to slowly infiltrate into the ground, lessening the burden on sewer systems when it is most important. Simply disconnecting spouts and allowing water to run down a driveway or walkway and into the street defeats the purpose. Additional rain garden guides: here and here.

◊ Use only organic fertilizers when necessary (excess can be washed into waterways), and don’t use pesticides.

◊ Grow native plants that help control erosion. Some examples (that naturally occur in many parts of the Pacific Northwest) include vine maple (Acer circinatum), madrone (Arbutus menzeisii), Oregon white oak (Quercus garryana), oceanspray (Holodiscus discolor), serviceberry (Amelanchier alnifolia), salal (Gaultheria shallon), nootka rose (Rosa nutkana), sword fern (Polystichum  munitum), kinnikinnick (Arctostaphylos uva-ursi), and inside-out flower (Vancouveria hexandra).

◊ Employ rain barrels to collect rainwater runoff from building roofs for irrigation during dry weather (if you can’t disconnect a downspout).

◊ Conserve water simply by taking very short showers, never letting the faucet run unnecessarily, and fixing any leaks (just as you would during droughts!).

◊ Collect “graywater” and use it onsite to reduce sewage discharges year round. Beware: this takes some ingenuity and planning!

◊ Never dispose of chemicals (like anti-freeze) by pouring it on the ground or into storm drains. Even drops of oil that seem relatively contained in your driveway can easily be swept into local waterways by rain. If you get an automotive oil leak, catch the oil in a pan and get it fixed ASAP.

© 2015 Eileen M. Stark

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A Winter Treat: Licorice Fern

When most Northwest ferns have said adiós to most of their aboveground growth and have nearly left the stage, enter licorice fern. If it’s growing in your yard you might forget it’s there until the soft rains of autumn release it from its dormancy. Then—when you least expect it—bright green, featherlike, fronds (to about 12 inches) appear and help brighten the landscape all winter long. Though it may stay evergreen where it is well established, receives some moisture in the form of mist or from a watering can, and is out of harsh sunlight, it is typically a summer-deciduous plant.

Licorice fern occurs naturally in cooler parts of the Pacific Northwest (west of the Cascades) and near the California coast (as well as small parts of the Sierra Nevada), at low elevations. It is a primary producer for other inhabitants within the ecosystem, including insects, birds, and other animals.

Its botanical name, Polypodium glycyrrhiza, means “many footed” and “sweet root,” and refers to creeping rhizomes that taste like licorice (which I’ve yet to try). Native Americans used the rhizome to sweeten foods and unpalatable medicines, but they also used it as medicine itself, to treat sore throats and upper respiratory infections. Modern herbalists use it for similar purposes.

Licorice fern is one of those multitalented plants that occurs naturally in multiple habitats. The next time you walk under a massive, mature deciduous tree like big-leaf maple or even an American elm, look upwards and there’s a good chance you’ll find it growing as an epiphyte on trunk and branch bark, particularly in crotches or on horizontal limbs that usually stay wetter than vertical ones. It’s also found growing on downed wood like logs and stumps, and as a lithophyte in rocky outcrops and mossy ledges.

 

Rescue mission

I rescued the ferns that now grace my yard from a mature street tree that had the misfortune to be cut down in my neighborhood a few years ago. The tree’s upper branches were nearly covered with the ferns, so when the fallen logs lay in the street awaiting transport, I peeled off about 6 feet of bark adorned with the featherlike fronds, their roots firmly and securely attached to the bark. I placed sections of the leafy mats under some native shrubs in the shady part of my back yard, where the soil is fairly rich, slightly acidic, and where moss grew readily (and not too far from the hose, since I figured they would need to be kept moist for a couple of summers). I also placed some logs, leftover from fruit tree pruning sessions, immediately next to them. Now the mats have come to life again, and I think they are quite settled in, judging by a new little plant not too far from its parents—spores are in the air!

Try it at home

If you’d like to try growing licorice fern in your yard, pick a spot that’s naturally mossy, since most areas that support moss ought to be able to support this fern. And be sure that you can get to it easily with a watering can while the plants are young; they will need to be kept moist—but not saturated—until they’re established (at which time they will become self-sufficient, except during exceptionally hot periods when I like to give dormant plants an occasional splash of water).

If you don’t have moss growing in your garden, try nestling a plant between shaded, half-buried rocks that have been covered with a slightly acidic, humusy and well-draining soil amendment like leaf mold. Or, try licorice fern’s close relation, Polypodium hesperium—it can take drier conditions and grows naturally in rocky places on both sides of the Cascades. Its short stature makes it a lovely addition to nooks and crannies of stone walls, as well as a candidate for creeping through a mostly shaded rock garden. Licorice fern’s other Northwest relative, P. scouleri, is a leathery-leaved gem that grows along the foggy coastline from British Columbia, south into California. But it is reportedly difficult to cultivate so should just be left alone to bask in salty mist.

As always, buy all native plants from reputable nurseries and never harvest from the wild. Or, rescue them from doomed situations, preferably at a time that will benefit the transition.

What Makes Leaves Change Color?

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

Darkness rules

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

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

As fall moves forward, the cells in the abscission layer become drier and weaker and leaves eventually part company with the plant. Many trees and shrubs lose their leaves when they are still colorful (making for some gorgeous mulch), while some retain the majority of their foliage through much of winter, though their leaves lose color fairly quickly. Like chlorophyll, the other pigments eventually break down in light or when frozen. The final pigments are tannins, which look brown.

Recipe for color

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

Plant natives!

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

 

© 2015 Eileen M. Stark

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Fall Plantings Bring Spring Flowers: Best Early-Flowering Pollinator Shrubs for the Pacific Northwest

Plan ahead for hungry native bees that 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 flowers in late winter and early spring for emerging bees as well as hummingbirds, to help you endure the gray winter skies, and to get the most bang from your buck, add early-flowering native shrubs to your garden. Get new shrubs in the ground soon—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, 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 unpruned hedgerows. When choosing any shrub, note its eventual width to be sure you have enough space for it to stretch its limbs at maturity—and to prevent a hack job by a pruner.

Scouler 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 host plant for several butterfly species. Does not tolerate full shade. Prefers moist soil. 20-30 feet tall by 10-15 feet wide. 

 

 

Indian plum (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 (it typically grows 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.

 

 

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

Red-flowering currant (Ribes sanguineum): An upright, deciduous shrub with nearly year-round appeal. Gorgeous, pendulous flower clusters (pictured, top) that bloom in early spring are followed by powder-blue berries. Leaves turn golden in late autumn. 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 6-8 feet wide.

Tall 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. 5-8 feet tall by 3-6 feet wide.

 

Another handsome winter bloomer is 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.

All of these shrubs are drought tolerant when established, although Scouler willow does best with supplemental summer water, and all will appreciate some irrigation in very hot situations.

After planting: Add a few inches of organic matter as mulch around the shrub (but not on its 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 (undecomposed chips and bark can deplete soil of nitrogen during breakdown).

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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