American Elm

All posts tagged American Elm

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. 

This is the American Elm in my backyard that attracts zillions of aphids in the fall. In turn, lots of migratory songbirds feast in the tree.

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.

This Northern Parula hung around the tree for a while, getting its fill of aphids.

This Blackpoll Warbler fed on the tree all morning. It was very tame and allowed a close approach. Here it is picking an aphid off a branch.

This Palm Warbler stopped in briefly to feed at the American Elm.

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. 

I was very surprised to see a Black-capped Chickadee feeding in the tree on insects. This bird is a rare migrant where I live near Kennett Square, PA. The resident Carolina Chickadees pay no attention to the aphids, preferring to feed at the regular bird feeder.

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. 

Ladybug Beetle larva are also attracted to the elm tree to eat the aphids. Check out the winged aphids all around the larva.

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.

This Ruby-crowned Kinglet hovers to pick aphids off a leaf.

You can see some of the aphids buzzing around the head of this Tennessee Warbler, which was another fantastic bird to see in the tree.

For more information on native plants in the backyard landscape, check out Bringing Nature Homeby Douglas W. Tallamy.