Creating a Bird-Friendly Garden
My interest in writing this article started with a discussion with my husband over a decade ago about who should clean the bird feeder. Actually, the original argument was not about who should clean the feeder, but WHY anyone should need to clean the bird feeder. I had read an article from a now unremembered source warning that cleaning a bird feeder on a regular basis was necessary to prevent the spread of disease. The picture I imagined was of people gathered around an office water cooler sharing a communal cup, even during flu season. “We” decided to each take responsibility for cleaning the feeder, with a lot of dire warnings from me about what would happen if only one of us followed through. I’ll let you come to your own conclusion about the outcome.
BIRD FEEDER STUDY IN GREAT BRITAIN
More recently, I discovered a report released by the Zoological Society of London based on 25 years of data showing that bird feeders can promote the transfer of diseases between birds by “encouraging birds to repeatedly congregate in the same location, often bringing them into regular contact with other species they wouldn’t otherwise interact with so closely in the wider environment. Risks can be increased if hygiene at feeding stations is poor, allowing stale food, food waste, and droppings to accumulate.” The data was analyzed for diseases caused by bacteria, viruses and parasites.
The study doesn’t suggest that people have to throw away their bird feeders. In fact, that would be a tall order since an estimated 48% of households in Great Britain provide supplemental bird food. The report calls on all who feed wild birds to be aware of their responsibilities for preventing disease. Simple steps include:
- offering a variety of food from accredited sources
- feeding in moderation, so that feeders are typically emptied every 1-2 days
- regular cleaning of bird feeders
- rotation of feeding sites to avoid accumulation of waste food or bird droppings
After reading these warnings, I can’t help but wonder how many bird lovers actually follow these recommendations. I am reminded of a neighbor many years ago who faithfully filled a plexiglass bird feeder that was about 36” long and 6” in diameter. I would bet many bags of black sunflower seeds that despite my neighbor’s very generous investment of time and money to keep the feeder filled, it was never cleaned.
CLEANING BIRD FEEDERS
According to Cornell’s Project FeederWatch, bird feeders should be cleaned once every two weeks. Take the feeder apart and remove any visible debris. Then, soak the feeder for 10 minutes in a diluted bleach solution (1 part bleach to 9 parts water), or soak for one hour in a weak vinegar solution (1 part white vinegar to 4 parts water) and then scrub with a clean bottle brush. Rinse thoroughly and let dry completely before refilling with seed.
A BETTER VISION
Instead of a yard full of sparkling clean plexiglass bird feeders and a vision of colorful birds chirping in gratitude, a better goal is to create a yard that will attract birds through natural food sources. Does this mean replacing sacks of premixed bird seed with an equivalent array of bird food from seed-producing plants? It is good to leave the seed heads of plants to provide food over the winter. Likewise, berry-producing shrubs and trees are important food sources. However, the most important food source for terrestrial birds is insects.
NATIVE PLANTS AND INSECTS
According to Doug Tallamy in his book, Bringing Nature Home, 96% of the terrestrial birds in North America rely on insects and other arthropods (typically, the spiders that eat insects), to feed their young. Tallamy is known for his work in studying the food web interaction among native plants, insects, and wildlife. Up to 90% of all phytophagous (plant-eating) insects are considered specialists because they have evolved in concert with only a few plant lineages. Insect species eat plants with which they have a long evolutionary history. Therefore, if we want to provide birds with their main food source of insects, then we need to provide the native plants that feed these insects.
In addition to improving wildlife habitat, a garden of native plants is well-adapted to local weather and soil conditions. They require little or no fertilizer and are relatively low maintenance.
If this subject is of interest to you, please take time to refer to the National Wildlife Federation’s Native Plant Finder website which is based on the work of Doug Tallamy and provides a listing, according to ZIP code, of native plants, grasses, trees, and shrubs and the number of insects supported by each. It’s amazing.
CREATING A BIRD-FRIENDLY YARD
Plants provide food, but they also offer shelter, nesting sites, and protection from predators. A multi-leveled planting design is recommended to satisfy each bird species’ elevation preference for feeding, roosting, and nesting.
- Plant tall canopy trees such as oaks (Quercus), elms (Ulmas spp.), and tulip trees (Liriodendron tulipifera).
- Underplant with shorter, more shade-tolerant trees, such as flowering dogwood (Cornus florida) and serviceberry (Amelanchier).
- Plant lower-growing, berry-laden shrubs, such as high bush blueberry (Vaccinium corymbosum), winterberry (Ilex verticillata), and chokeberry (Aronia).
- At the lowest level, add groundcovers that provide berries and cover such as creeping juniper (Juniperus horizontalis ‘Emerald Spreader’), and partridge berry (Mitchella repens). Or, choose groundcovers that provide cover such as barrenwort (Epimedium), wild ginger (Asarum canandense) and sedge (Carex spp).
- In a sunny location with room for plants to expand, plant native grasses to provide seed and some cover from predators. Options include little blue stem (Schizachyrium scoparum), big blue stem (Andropogon gerardii), river oats (Chasmanthium latifolum), and switchgrass (Panicum virgatum). For more information on ornamental grasses, see The Garden Shed, Nov. 2017.
- Consider native vines that are attractive to birds and to insects such as: crossvine (Bignonia capreolata) attracts hummingbirds; wild passion flower (Passiflora incarnata); and Dutchman’s pipe (Aristolochia tomentosa), the larval host plant for pipe vine swallowtail butterfly.
- Break up broad expanses of lawn with island plantings of trees, shrubs, and ground covers.
Plant native perennials so that bloom periods stretch from beginning to end of season. An example in bloom order of perennial selections that would offer a succession of blooms from spring through late fall includes: wild bleeding heart (Dicentra eximia), wild geranium (Geranium maculatum), penstemon (Penstemon digitalis), tickseed (Coreopsis spp.), purple coneflower (Echinacea purpurea), orange cone flower (Rudbeckia fulgida), sunflower (Helianthus spp.), goldenrod (Solidago spp), and aromatic aster (Symphyotrichum oblongifolium).
You may also refer to a very helpful guide provided by the Virginia Cooperative Extension publication, “For the Birds, Butterflies and Hummingbirds: Creating an Inviting Habitat.” The chart highlights the types of birds that benefit from specific native plants and the time of bloom.
A DRINK FOR THE THIRSTY
Birds require a consistent supply of fresh water for drinking and bathing. Consider bird safety when locating the birdbath. Although some birds prefer baths at ground level, a pedestal birdbath provides some protection from cats. For added protection, locate the bath out in the open, at least 10′ from predator cover such as a hedges or shrubs. The preferred bird bath gradually inclines to a depth of no more than 2-3″ at the deepest point. The surface should be slightly textured to provide sure footing. Just as with bird feeders, it is important to keep bird baths clean and to supply fresh water.
FINDING NATURAL FOOD IN WINTER
Common bird species that do not migrate, such as northern cardinals, woodpeckers and mockingbirds, depend in winter on berry-producing shrubs. Although the berries are produced earlier in the year, many are left on the plant into winter when other more favored food sources are spent. Consider choosing native berry-producing trees and shrubs based on the Native Plant Finder cited above:
- Arrowwood viburnum (Viburnum dentatum)
- Chokecherry (Prunus virginiana ‘Schubert’); susceptible to pests, weak limbs in snow
- Eastern red cedar (Juniperus virginiana)
- American black elderberry (Sambucus canendensis); spreads through suckers
- Red elderberry (Sambucus racemose); spreads through suckers
- Fragrant sumac (Rhus aromatica)
- Inkberry (Ilex glabra); spreads through suckers
- Serviceberry (Amelanchier spp.)
- Winterberry holly (Ilex verticillata)
Insects are the primary food source for terrestrial birds, and insect species eat plants with which they have a long evolutionary history. Therefore, a selection of native plants creates the most bird-friendly environment. Growing diverse plants that fruit at different times of the year helps to provide a continuous supply of food year-round. For those who choose to feed birds, research has shown that keeping bird feeders clean, providing fresh seed, cleaning up around the feeding area, and offering clean water are all essential steps for keeping birds healthy.
Landscaping for Winter Birds, The National Garden Association, https://garden.org/learn/articles/view/764/
Landscaping with Birds in Mind, The National Gardening Association, https://garden.org/learn/articles/view/190/
“Feed the birds? Scientists highlight risks of disease at garden bird feeders,” https://www.zsl.org/science/news/feed-the-birds-scientists-highlight-risks-of-disease-at-garden-bird-feeders
“Health hazards to wild birds and risk factors associated with anthropogenic food provisioning,” https://royalsocietypublishing.org/doi/full/10.1098/rstb.2017.0091
Native Plant Finder, https://www.nwf.org/NativePlantFinder/Plants/2732
“For the Birds, Butterflies and Hummingbirds: Creating Inviting Habitats,” VCE, https://pubs.ext.vt.edu/content/dam/pubs_ext_vt_edu/HORT/HORT-59/HORT-59-PDF.pdf
“Why planting a garden is better for bird-watching than filling a feeder,” Mother Nature Network, https://www.mnn.com/earth-matters/animals/blogs/why-planting-garden-better-bird-watching-filling-feeder
“10 Plants for a Bird-Friendly Yard,” https://www.audubon.org/news/10-plants-bird-friendly-yard
“How to Plant Your Yard to Attract Songbirds,” Audubon Society of Northern Virginia, http://audubonva.org/new-page-3
“Virginia Natives for Attracting Birds,” http://www.virginia.edu/blandy/blandy_web/arboretum/virginia_natives_for_birds.pdf
“Ornamental Grasses: easy, beautiful and — invasive?” http://piedmontmastergardeners.org/article/ornamental-grasses-easy-beautiful-and-invasive/