Feeding the Birds, Au Naturel
Contributor
- Topics: Growing for Biodiversity, Plants You Need
Spring/Summer 2023
Creating a landscape more like Mother Nature comes with benefits, not the least of which is attracting birds to one’s garden. We’ve known for a great many years that installing plants which produce fruit and seed provides a key enticement for songbirds. Now we’re catching on that there’s more to this feeding naturally idea than fruit and seed plants. There’s an additional food source, maybe a better one overall, which doesn’t just draw birds into the garden for our own viewing pleasure, it also goes a long way toward improving a habitat’s greater biodiversity and hence making that small but important difference we need in the world today.
WHAT BIRDS NEED
So what is that additional, better food source? Let me start with the bigger picture. As with all living organisms, birds need shelter, water, and food. Plants can provide the shelter, the food, and at least a little water. You somehow supply the bulk of the water.
Shelter can be trees, shrubs, heavy vines. A windbreak of trees, especially the dense and somewhat prickly kinds such as pines, provides a calm haven for the smallest birds.
The most popular approach to providing shelter has been to buy or build nest boxes (birdhouses). In the Pacific Northwest, nest boxes are used by Bewick’s wrens (Thryomanes bewickii), house wrens (Troglodytes aedon), chickadees (Poecile atricapillus, P. rufescens, P. gambeli), nuthatches (Sitta canadensis, S. pygmaea, and S. carolinensis), swallows (Tachycineta bicolor and T. thalassina), western bluebirds (Sialia mexicana), American kestrels (Falco sparverius), wood ducks (Aix sponsa), pileated woodpeckers (Dryocopus pileatus), barred owls (Strix varia), and northern pygmy-owls (Glaucidium californicum), among several other owls. The internet is loaded with detailed plans for specific boxes. Should you go the nest box route, watch for the common “weed birds,” though, the introduced species which will commandeer nest boxes: European starlings (Sturnus vulgaris) and house sparrows (Passer domesticus).
Then there’s the very natural choice of allowing dead or dying trees to remain on the property. Snags, as they are called, are excavated and used by cavity-nesting birds such as woodpeckers, owls, western bluebirds, chickadees, and wrens. Although excellent habitat features, dead trees may not be the chosen aesthetic feature in a small garden, but they are easily tempered on large properties and some may even consider them a focal point.
Water, at its ideal, is a natural pond, stream, vernal pool, or other standing or moving free water area on your property—if you’re lucky enough to have one, of course. Make sure to preserve or restore any such feature, as these are excellent aquatic habitats for a great diversity of wildlife beyond birds.
Otherwise, water can be supplied in a traditional birdbath, a small pond, a recirculating waterfall, or a shallow dish. Or simply dig a hole in the ground and line it with concrete. Birds especially like moving water (doesn’t have to be deep). Several devices are available that can be connected to the garden hose to create continuous dripping (for drinking) or misting (for bathing).
Food may be bird seed (of several kinds) put in hanging cylinders, on platforms, in socks, in hoppers, or in suet. Garden plants, too, provide several types of food for these same songbirds, especially when there’s a focus on planting those species which provide that better, additional food source.
Almost all plants serve up the fruits, seeds, nuts, or nectar that make up a primary menu for songbirds. Some plants, more importantly, become host to a very large variety of edible insects, particularly juicy caterpillars of butterflies and moths (Lepidoptera). What’s important about these caterpillars and other insects is that nearly all songbirds raise their young
on this diet. There’s generally a seasonal pattern of eating for songbirds—in late spring through summer, with the raising of nestlings and even some fledglings, they dine upon insects (gleaning on plants, beneath bark, or on the ground) while in late fall and winter, the menu changes to fruits, seeds, and nuts. This is not to say that your summer tree and cane fruits aren’t part of the opportunistic diet (the trade-off).
It’s best to concentrate on native trees, shrubs, and flowers in the plantings with an emphasis on those natives which biologists and ecologists have labeled “keystone species.” They are the species supporting a wicked good biodiversity, those many other species which depend on them. They are so exceptional, they represent somewhat of an 80-20 rule, with 20 percent of an ecosystem’s species being key to the other 80 percent. Bottom line, they pretty much hold together entire ecosystems.
When it comes to birds, it gets better than the 80-20 rule, with more than 90 percent of our terrestrial birds relying on the insects supported by those keystone plants. Oaks (Quercus spp.), particularly, just may be the poster children for keystone species because they have greater insect populations and greater numbers of species of insects than any other tree group. When it comes to just those juicy caterpillars for the birds, it goes up another notch—a mere five to 15 percent of our native plant species (the keystones) are supporting 75 to 90 percent of the caterpillars that are out there. It’s the caterpillars that will attract the greatest numbers of bird species to a garden. In addition to being attractive to important insect species, most of the keystone species also provide seeds, nuts, berries, and other fruits at times when insects aren’t numerous.
The keystone model was proposed in 1969 by zoologist Robert T. Paine and advanced more recently by entomologist-author Doug Tallamy. Although the concept somewhat simplifies complex ecological systems, it helps encourage increased communication between ecologists, conservation policymakers, and gardeners and landscapers in general.
Another, more process-oriented proposal, one called Soft Landings, complements and expands on the keystone idea. This companion plan was augmented and named by Leslie Pilgrim, founder and executive director of Neighborhood Greening and editor of The Butterfly Effect Journal, and Heather Holm, pollinator conservationist and author. Soft Landings encourages “diverse native plantings under the dripline of keystone native trees,” per Holm’s website. The “soft landing” literally refers to the plantings for the butterfly and moth caterpillars rappelling or crawling down to the ground to pupate after they’ve finished feeding on their keystone tree host plant.
With lawns shunned, “soft landings plantings provide the refuge for these beneficial insects to complete their life cycle right under the tree. The plantings also provide flowering plants for pollinators, refuge for other beneficial insects, and reduce the amount of turf grass in a residential landscape” (Bee and Pollinator Books by Heather Holm 2023, emphasis added). Most effectively, the chosen plants of a soft landings planting would themselves provide food for more caterpillars. That includes such keystone species as those within the genera for asters (Symphyotrichum) and goldenrods (Solidago).
I’ve provided a list focusing on keystone plants suitable for the Pacific Northwest. In the rest of the West, look for species within these genera: Alnus, Arctostaphylos, Ceanothus, Erigeron, Eriogonum, Helianthus and related genera, Lupinus, Pinus, Populus, Prunus, Quercus, Ribes, Salix, Solidago, and Symphyotrichum. All are found in selected ecosystems throughout the Pacific states.
Some traditional non-native garden plants can be nearly as effective in this function, provided they are botanically related to the native, keystone plants listed.
Article Continues Below Plant Recommendations
PLANTS FOR ATTRACTING BIRDS TO THE GARDEN
Western Pacific Northwest
This list was compiled and adapted from the National Wildlife Federation (“Keystone Plants for Wildlife”), the Washington Ornithological Society (“Resources for Adding Native Plants To Your Garden: Hostplants for Butterflies and Moths in WA”), and Selecting Plants for Pacific Northwest Gardens (a book written by the author of this article).
These are the plants that provide food primarily in the sense they are insect attractants themselves, and a few provide fall-winter fruits. Most of these are the “keystone” species in that they feed the young caterpillars of almost all of our native butterflies and moths. I have focused on plants that have a worthy ornamental value in the landscape comparable to introduced plants; certainly a subjective view but one that helped me narrow what could have been a vast list down to a friendlier assortment.
TREES
Acer glabrum, ROCKY MOUNTAIN MAPLE
Acer macrophyllum, BIGLEAF MAPLE
Acer negundo, BOX ELDER
Alnus incana, GREY ALDER
Alnus rhombifolia, WHITE ALDER
Betula papyrifera, PAPER BIRCH
Crataegus douglasii, PACIFIC HAWTHORN
Malus fusca, OREGON CRABAPPLE
Pinus contorta, including both P. c. ssp. latifolia (LODGEPOLE PINE) and P. c. ssp. contorta (SHORE PINE)
Pinus ponderosa, PONDEROSA PINE
Populus balsamifera ssp. trichocarpa, BLACK COTTONWOOD
Populus tremuloides, AMERICAN ASPEN
Prunus emarginata, OREGON CHERRY
Prunus virginiana, CHOKECHERRY
Quercus chrysolepis, CANYON LIVE OAK
Quercus garryana, OREGON WHITE OAK
Quercus kelloggii, CALIFORNIA BLACK OAK
Salix lasiandra, SHINING WILLOW
Sambucus cerulea, BLUE ELDERBERRY
Sambucus nigra ssp. canadensis, BLACK ELDERBERRY
Sambucus racemosa var. arborescens, COAST RED ELDERBERRY
SHRUBS
Acer circinatum, VINE MAPLE
Arctostaphylos columbiana, HAIRY MANZANITA
Arctostaphylos uva-ursi, KINNIKINNICK
Ceanothus at least five species, WILD LILAC
Cornus, especially C. occidentalis (WESTERN RED OSIER) and C. sericea (formerly C. stolonifera; RED-OSIER DOGWOOD)
Holodiscus discolor, OCEANSPRAY
Malus fusca, OREGON CRABAPPLE
Philadelphus lewisii, LEWIS’S MOCK ORANGE
Physocarpus capitatus, PACIFIC NINEBARK
Quercus garryana var. breweri, BREWER’S OAK
Quercus sadleriana, DEER OAK
Quercus vacciniifolia, HUCKLEBERRY OAK
Rhododendron macrophyllum, PACIFIC RHODODENDRON
Rhododendron occidentale, WESTERN AZALEA
Ribes acerifolium, MAPLE-LEAF CURRANT
Ribes laxiflorum, TRAILING BLACK CURRANT
Ribes sanguineum, RED-FLOWERED CURRANT
Rosa, four species, ROSE
Rubus, several species, some less assertive than others, BLACKBERRY, RASPBERRY
Salix scouleriana, SCOULER’S WILLOW
Salix sitchensis, SITKA WILLOW
Sambucus racemosa, RED ELDERBERRY
Symphoricarpos albus, SNOWBERRY
Vaccinium caespitosum, DWARF BILBERRY
Vaccinium membranaceum, BLACK HUCKLEBERRY
Vaccinium ovalifolium, OVAL-LEAF BLUEBERRY
Vaccinium ovatum, EVERGREEN HUCKLEBERRY
Vaccinium parvifolium, RED HUCKLEBERRY
Viburnum edule, SQUASHBERRY
Viburnum ellipticum, WESTERN BLACKHAW
Viburnum trilobum (formerly V. opulus var. americanum), CRANBERRY-BUSH
PERENNIALS
Agastache occidentalis, WESTERN GIANT-HYSSOP
Agastache urticifolia, NETTLE-LEAF GIANT-HYSSOP
Anaphalis margaritacea, PEARLY EVERLASTING
Balsamorhiza deltoidea, PUGET BALSAMROOT
Erigeron compositus, CUT-LEAF DAISY
Erigeron glacialis, GLACIER FLEABANE
Erigeron speciosus, SHOWY DAISY
Erigeron subtrinervis, THREE-VEINED FLEABANE
Helianthus petiolaris, PRAIRIE SUNFLOWER
NOTE: Helianthus annuus, the annual, common sunflower, is native here and when and where possible, seeds of our species, not cultivars, not hybrids, should be used
Lupinus albicaulis, SICKLE-KEEL LUPINE
Lupinus latifolius, BROADLEAF LUPINE
Lupinus polyphyllus, LARGE-LEAVED LUPINE
Lupinus sulphureus ssp. kincaidii, KINCAID’S LUPINE
Solidago elongata, WEST COAST GOLDENROD
Solidago lepida, WESTERN GOLDENROD
Solidago multiradiata, ROCKY MOUNTAIN GOLDENROD
Solidago simplex ssp. simplex var. nana, DWARF GOLDENROD
Solidago spathulata, COAST GOLDENROD
Symphyotrichum (Aster) jessicae, JESSICA’S ASTER
Symphyotrichum (Aster) laeve, SMOOTH ASTER
Symphyotrichum (Aster) lateriflorum, CALICO ASTER
Symphyotrichum (Aster) subspicatum (S. douglasii), DOUGLAS ASTER
This list of plants is provided with the hopes that each gardener will research the plants thoroughly to find those which match the natural ecosystem nearest to their garden. None of these plants grow everywhere, of course. Some are Washington natives exclusively, some Oregon natives, and some are northern California endemics. Even within their ranges, it’s important to note that each plants finds its home in a particular ecosystem and matching that ecosystem and its corresponding assemblage of plants is the preferred way to go.
WHEN IT COMES TO PLANTING
Start by restoring any native plant community on or surrounding your property. Remove weeds and other undesirable exotics; this is especially important since our native plants and wildlife have coevolved, and introduced ruderal species (“weeds”) can suppress regeneration of native ecosystems. Check with your county ag or extension office for a list of the truly “invasive” and “noxious” weeds.
Distribute your chosen plants throughout the landscape rather than make the “bird garden” a tiny token plot somewhere in the garden. It’s perfectly possible to develop an entire landscape design around a bird-friendly plant list.
Create diversity. Plant a lot of different things. Of course, the number of species you plant will depend on the size of your property. But don’t be disillusioned if you can’t get a thousand different species in your landscape. Plant as many as seems appropriate for the space and the flying beasties will love you. Biodiversity begets biodiversity; native birds (and other tiny native critters) are one of our most recognizable indicators of biodiversity (second to the largely unrecognized living community of the soil, of course).
Plant for all seasons. Include several different species to provide a year-round supply of flowers, fruits, seeds, leaves, and the bugs which eat them.
Provide shade. You don’t need a giant oak to cast a worthy shadow. Create clusters or groves of each species you choose and, on larger properties, create multiple groves, each with their own individual species. Groves allow trees to be planted much more closely than with planting of mixed species and groves provide adequate shade. By the way, oaks don’t need to grow one hundred years to become grand and beautiful. Most are fairly fast growing and will reward you with a beautiful tree easily within 10 years.
Layer up. Use tall trees, small trees, shrubs, groundcovers, and perennials to create layers of growth. Give the birds opportunities to move up and down in their foraging.
Think big. Put in masses of the keystone species or the birds’ most-favored seed and fruit species, not just one or two plants. Somewhat conversely, think small; grow plants in containers where space is limited.
“Soft landing” plants are best installed under and around young, preferably newly planted trees to allow the combination to develop together. Planting at the base of older, established trees has its difficulties, including the potential to damage tree roots by digging as well as the often strenuous exertion by the gardener in the simple act of digging holes in soil compacted by and tangled with large roots.
If you use non-native plants, do not use weedy exotics that spread by seed. For example, avoid butterfly bush (Buddleja davidii), English ivy (Hedera helix), Japanese honeysuckle (Lonicera japonica), and cherry laurel (Prunus laurocerasus). Invasive and noxious weed species love taking bird rideshares for seed dissemination.
MORE WAYS
Don’t forget about the food items on and in the ground. Allowing leaf litter to build up under shrubs and trees will ensure a good supply of insects and other tiny morsels for the ground-feeding duff scratchers such as towhees, thrushes, many species of sparrows, and the familiar American robin. Speaking of ground, create a dust bath for the birds—leave a few square feet of bare area, wherein there are no plants, no cover, and no mulch.
All wild birds, including their nests and eggs, are protected by law. Before any pruning anywhere, particularly in spring, consider the nesting habits of native birds. During their nesting season, birds may make use of garden trees, shrubs, vines, and hedges, and with some birds, even on the ground. (This certainly doesn’t apply to nest boxes, of course.) Nests are often well hidden, so look carefully. Trim fruit-producing shrubs, hedges, vines, and trees after the berries are gone. Letting formal hedges go at least a little informal is a win-win: food for the birds, less maintenance for you.
Leave carefully chosen grass plumes and seed heads. Not all plants produce bird-attractant seed heads; know those species which have been described as viable attractants through fall and into winter. Members of the sunflower family (Asteraceae)—including and especially asters, balsamroot (Balsamorhiza), goldenrods, and sunflowers in the PNW—are particularly attractive to finches and grosbeaks. These same flower groups range all the way down into Southern California where gardeners can additionally employ various native tickseeds (Coreopsis) and coneflowers (Rudbeckia).
Lawns aren’t the best environments for birds (although large lawn areas seem attractive to American robins, killdeer, and various pipits). If you do have a lawn and plan to keep it, mow it high and allow some of it—the edge at the least—to go fairly unmown, especially during the migration seasons (in the PNW, spring migration peaks in April and fall migration peaks early October).
Don’t just attract birds to your yard—protect them once they’re there. Start by moving bird feeders and water sources at least 30 feet from windows. Make window glass visible to birds using stickers, strings, or film in a two-inch-by-four-inch pattern; research brands as some are more effective than others. Move large houseplants away from windows. At the least, close blinds and keep screens on windows year round (when you’re not focusing your binoculars on the birds while sitting at your dining room table, of course).
Keep cats out of the landscape. I’ll avoid the statistics about cat-bird interactions and not get into the controversial aspects of this subject, but I will, in the least, direct everyone to the many online articles on humane ways to prevent stray and feral cats from entering your personal bird reserve.
ADDRESSING THE TRADE-OFF
No doubt the whole idea of giving over the landscape to caterpillar host plants is the extreme antithesis to the core beliefs of the conventional gardener who grows with the intent of producing pest-free specimens. We are essentially suggesting here that gardeners install plants which are to be eaten. But not by us.
I suppose the optimum “garden” for our native birds is allowing Mother Nature—in the guise of whatever ecosystem was there before development—to have the space back in toto, maybe with a bit of help from us. A compromise, for sure, with the biggest hand given to a truly natural habitat. And maybe a “garden for the birds” suggests the garden is just for the birds, no longer for the gardener.
Maybe we must avoid the pervasive question, “What can they do for us?” and ask, “What can we do for them?” This is part of the bigger appreciation-to-save-the-earth picture as we address all of nature as a whole. Our gardens were once part of their homes and giving back even a little is the right thing to do.
This is not so far-fetched, though; many gardeners already plant milkweed (Asclepias) specifically for monarchs (Danaus plexippus) to lay their eggs upon. So we’re already on the right track. Related notes: monarchs on milkweed are a bad example of bird attractants; birds don’t eat monarch caterpillars and monarchs are rare visitors, even as migrants, to the west side of the Pacific Northwest.
But as gardeners, we want more than that. We want to grow roses, exotic plants, vegetables, fruits, and so many celebrated plants. None of which come close to being keystone species (although they might be in their native habitats, wherever that is).
While native caterpillars on our native plants are encouraged for the birds, we have a different view when they attack our brassicas. The fruits of our cherry trees are not as willingly shared as are the fruits of the native Prunus.
So when we allow the “bird garden” part to feed the birds, we must protect the “your garden” part, at least some of which feeds us. Fortunately, protecting against doesn’t have to mean harming. Rather than apply any strategy or product which might interfere with the bigger picture within a landscape, you must focus on protecting those plants distinctly intended for you and not the birds. There are many ways to protect one’s garden from the bad beasties without resorting to pesticides, many of which end up in the bigger food web.
If you want fruit trees (the ones you plant for your own harvest), you will need to net them to protect the crop. Bird netting, available at every garden center, helps minimize damage to ripening fruits on trees or on the ground.
Although dark-colored netting is less intrusive to your eye, it is near invisible to a bird’s eyes and the bird may get tangled. Use brightly colored netting instead. Use one-inch mesh netting to exclude all birds but if only larger birds are the problem, you can use the less expensive 2.5-inch mesh.
The netting must thoroughly surround the tree (or ground plant), and it must be supported in some way so that there is at least a beak’s-length gap between the birds who may land on it and the actual fruit. The larger the fruit plant, the more engineering goes into a framework upon which the netting will be placed. The netting must be stretched tautly to make sure curious birds do not get caught in sagging netting. Check the netting at least twice daily for curious but now panic-stricken birds. Because many birds (such as jays, sparrows, finches, northern mockingbird, grosbeaks, and quail) will also eat the buds and blooms of fruit trees, it’s best to set up the netting just as the flower buds begin to swell. For a bit more money, go with chicken-wire netting; it’s longer lasting and tangle proof.
On a somewhat smaller scale, use floating row covers for covering newly sown seeds or small plantlets. Small-gauge chicken wire, too, can be placed over newly sown peas to stop them from being eaten by birds and mice while they are germinating.
Topdressing newly sown seeds is also an effective barrier. Cover seeds lightly (no more than a quarter inch), but thoroughly, with organic mulch (anything but peat). This helps hold in some moisture, as well as helps prevent too much seed theft by birds.
Just in case you’ve always wondered, scarecrows don’t scare away birds. Nor do rubber snakes, plastic owls, and “terror eye balloons” (big, bright orange and painted with huge eyes). At least not for long. Birds will adjust in time to whatever scare tactic the device offers.
Avoid noise makers, Mylar, other flashing items, and anything else which will disturb the birds you’ve intentionally attracted for the purposes of saving the world.
There are also some somewhat passive, almost Zen-like approaches to dealing with potential negative bird-plant interactions.
First, and a hard pest management strategy to swallow, is one which comes from agriculture’s process of integrated pest management. It’s the step of determining an acceptable injury level; in agriculture, it’s called the “economic injury level” and is based on comparing cost of input versus cost of output. I call my home garden version the “aesthetic injury level.” With no actual profits involved, we are therefore asked to accept a few nibbles here and there.
Another approach, as Doug Tallamy has suggested: put the caterpillar host foods, especially the species most heavily prone to munching, in the background. A far view rarely looks bad.
Acceptance is easier if you keep in mind that most of the insects—including the caterpillars that feed on keystone species—are host specific, and that means they attack that keystone species (and sometimes a few related species) and do not spend time on your exotic garden plants.
Also making it easier to accept is knowing that there is a very positive side of the trade-off—it is creating greater biodiversity wherein the plants, the insects they attract (both good and bad), and the birds will provide untold benefits to your overall landscape, including your edible and non-native ornamental segments. Once you become a “caterpillar rancher,” you kick your bird garden into bio-hyperdrive.
THE BIGGER STEPS AND BROADER STROKES
Learn more about local bird species. Find out what they eat, where and how they nest, and when they pass through your area during migrations, if they do.
Encourage your neighbors to plant for the birds, as well. Link up patches of habitat to provide the maximum benefit for wildlife suffering from shrinking native habitat Tie the “islands” together to develop the safe haven corridors all animals need. Coordinate natural green spaces in community and commercial areas.
Turn out the night lights. Artificial lights can disrupt biological clocks, hence impacting the timing of migration and other seasonal behaviors.
As already mentioned, make sure the surrounding wildlands remain wild.
There is plenty of published research that indicates just by increasing biodiversity in one’s garden, there is an increase in beneficial synergies more than there are negative trade-offs. You simply plant something and then wait for something amazing to happen.
Resources
Neighborhood Greening and its quarterly journal, The Butterfly Effect.
See the Soft Landings page on Heather Holm’s website.
For more information on keystone species, visit Doug Tallamy’s Homegrown National Park, his lecture “Native Keystone Plants for Wildlife” for the National Wildlife Federation, or the University of Washington’s page about the late Robert T. Paine regarding Paine’s ecology work and coining of the term.
Bee and Pollinator Books by Heather Holm. 2023. “My latest storymap features Soft Landings, a concept developed by Leslie Pilgrim of Neighborhood Greening and me.” Facebook, April 26, 2023.
Seals, Joe. 2021. Selecting Plants for Pacific Northwest Gardens.
Washington Ornithological Society. Resources for Adding Native Plants To Your Garden. [pdf]
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