The Loma Prietan - November/December 2012

Gardening Green

Is Your Garden for the Birds?

by Arvind Kumar

A cedar waxwing feeds on toyon berries at Lake Cunningham Park, San Jose.  Photo: Stephen Rosenthal
A cedar waxwing feeds on toyon berries at Lake Cunningham Park, San Jose. Photo: Stephen Rosenthal

Scientific studies are confirming what native plant gardeners have known for a long time: native plants in urban gardens offer birds a better refuge than lawns in the midst of the concrete-and-asphalt jungle. Toyon, coffeberry, Oregon grape, and blue elderberry all produce berries that the birds love.

Native plant gardens create bird habitat in urban areas

If you want to help the environment, start with your own garden. Reduce the garden’s footprint on the environment. Limit or eliminate the use of pesticides, herbicides, and synthetic fertilizers. Use less water and less energy.

Make your garden a welcoming place for birds, butterflies, lizards, insects, and other wildlife. How? By introducing native plants. What makes native plants so special? Native plants have coevolved with native wildlife for millennia, and offer unparalleled habitat value. There is a growing body of scientific evidence to confirm this.

Entomologist Douglas Tallamy’s book, Bringing Nature Home, contains the results of an interesting study. Non-native plants have been present on the east coast of the United States for over 500 years. East coast insects have had half a millennium to adapt to these non-native plants. Yet, even generalist insects—those that are not fussy about their diets—prefer native plants to non-native plants by a ratio of two to one (insects in general, four to one; caterpillars, 35 to one).

Environmentally aware home gardeners have observed that after they introduce native plants to the garden, the quantity and variety of bird life in the garden goes up. A new study conducted in Arizona confirms this, and adds more evidence that home gardens landscaped with native plants offer birds “mini-refuges” and help mitigate the loss of biodiversity in urban areas.

Urban ecologists from the University of Massachusetts Amherst and Arizona State University selected 20 home gardens in Phoenix: half had traditional lawns, the other half had native plant landscaping appropriate to the Sonoran Desert in which Phoenix is located. The study found that the native gardens attracted a more even bird community and offered superior habitat compared to the lawns.

The researchers placed bird feeder trays in each garden and monitored the birds visiting the trays over a 24-hour period. With the help of video camcorders, they counted every peck by every bird and weighed the remaining seed to calculate the quantity of seed consumed.

They found that the native gardens attracted more native bird species, while the lawns attracted more synanthropic (human-following) species like house sparrows. The birds in the native garden spent less time at the feeder, ate less seed off the feeder, and spent more time foraging elsewhere in the garden.

The takeaway from these studies is that urban development need not lead to a complete and total loss of habitat. If we plan wisely and plant wisely, we can share urban spaces with birds and other wildlife. Urban planners and landscape designers should take note, but you, the homeowner, have the final word on what grows in your garden. Choose nature, choose native plants, choose life!

*  *  *

Here are some excellent berry-producing plants for California gardens.

Late fall and early winter is the time when toyon (Heteromeles arbutifolia) is at its aesthetic and ecological peak, its branch tips laden with bunches of succulent, shiny red berries. Cedar waxwings and robins will soon be seen gorging on the ripe berries, picking each bush clean before moving on. This large shrub is attractive throughout the year with neat green foliage, and its tiny white flowers attract masses of pollinators. Prefers sun, but will develop into a small tree in shadier locations.

Fall is also the time that the California coffeeberry (Frangula californica, formerly Rhamnus c. ) bears fruit: green berries that turn maroon before maturing into their characteristic chocolate color. Tiny flowers in spring are not noticeable to humans but are a magnet for hummingbirds and native bees. Grows in sun as well as part shade. Neat and tidy all year long without much maintenance. Many cultivars available in the trade. Mound San Bruno grows to 6 feet.

The state shrub of Oregon, Oregon grape (Berberis aquifolium), is found in California as well and grows well in part shade. Shiny leaves are tipped with prickles. Yellow flowers in spring turn into clusters of purple berries in fall, loved by birds. Low maintenance and attractive all year long. Comes in upright and prostrate forms.

Few plants are as beloved of songbirds as the blue elderberry (Sambucus nigra caerulea, formerly S. mexicana). This multi-trunked large shrub can easily be pruned and trained as a small tree to 20 feet. Cream flower-sprays in spring turn into pale blue berries by June that attract a wide diversity of birds. Fast growing and winter deciduous.

Plant it and they will come!

Sierra Club life member and California Native Plant Society board member Arvind Kumar grows native plants in his Evergreen garden. He can be reached at chhaprahiya@yahoo.com.