By Joe Sebastiani, Seasonal Program Team Leader
In the autumn, the best bird feeder in my yard is not plastic and filled with seeds…it is an American elm tree. This tree, which was planted in the backyard 10 years ago literally swarms with aphids each and every fall. They buzz around the tree, line every crack, and coat every branch. Walking past the tree, you must go through a fog of these tiny, winged insects.
These little insects attract small songbirds which gorge themselves at this tree from about mid-September through October. Earlier this year, a Cape May Warbler spent two days feeding at the tree. This week, a Brown Creeper inched its way up the trunk, plucking aphids at every hitch. Today, however, was the big show of the season so far. At about the same time, the following species were in the tree feeding: Ruby Crowned Kinglet, Golden-crowned Kinglet (several of each), Blackpoll Warbler, Tennessee Warbler, Yellow-rumped Warbler, Palm Warbler, Northern Parula, Magnolia Warbler, Nashville Warbler, and a Downy Woodpecker.
I watched the birds feed for a few hours this morning. Mostly, they allowed me to get quite close, since they were very preoccupied with feasting on the thousands of insects that coat the tree. Later in the morning, I saw a chickadee getting in the act as well. Since I’ve never seen a chickadee eat the insects before, I looked a little harder. It turned out to be a Black-capped Chickadee, which is rare where I live in southern Chester County, PA. My resident Carolina Chickadees would rather stick to the plastic kind of feeder filled with seed.
This is exactly why we should plant native plants in the backyard. Native plants attract insects which attract birds and other predatory insects and so on. Today I can see how even just one tree can support dozens and dozens of birds, possibly hundreds over the course of the fall migration when they stop to refuel here.
American elms have mostly succumbed to the introduced Dutch Elm Disease and there are few in the ecosystem around us. My elm is genotype that has been developed that is resistant to this disease. Just imagine the impact American elms had in the ecosystem when they were commonly found in our area.
For more information on native plants in the backyard landscape, check out Bringing Nature Homeby Douglas W. Tallamy.