Trees for Birds
March 29, 2017
If you love birds, and you plant trees or shrubs this spring, please choose native plants.
Songbird nestlings grow fat and healthy on caterpillars, the larvae of moths and butterflies. If you care about birds, this is worth knowing. By planting trees with leaves that caterpillars like to eat, your yard can become an avian buffet.
This means planting native trees. Entomology professor Douglas Tallamy, in his acclaimed book Bringing Nature Home, revealed the stunning differences in caterpillar production between native trees and European or Asian imports.
One jaw-dropping comparison is between Asian gingko and native oak. Three species of caterpillars in North America have been found feeding on gingko, while over 500 have been found on oak.
Anecdotally I’ve seen this contrast in my own yard. I once had a large Norway maple. Its foliage remained largely untouched through the growing season. Most caterpillars and other insects obviously couldn’t eat the leaves. My Norway maple was about as bug-friendly as a plastic house plant.
Even more immune to insect attack, and consequently even further removed from any meaningful ecological connections, were two magnolia trees. Their foliage was perfectly pristine – always.
The leaves on my native red oak, white birch and white elm by contrast were blemished and perforated by insects. This, understand, is not a sign of impending doom for a tree, but testimony that the tree is contributing to ecological health.
In the April 2017 issue of BirdWatching magazine, Marina Ritchie compared native trees to “overflowing, self-replenishing bird feeders” and non-native trees to empty feeders “with no refills in sight.”
So if you love birds, and you plant a tree this spring, please choose a self-replenishing bird feeder. Let’s help fill the larders of our precious songbirds.
Superb trees for caterpillars include oaks, black cherry, native willows, birch and poplar. See www.bringingnaturehome.net/what-to-plant.html for a complete list. And head over to the Not So Hollow Farm Native Plant Showcase, to find out more about native plants in the hills.