Viburnum leaf beetle

Viburnum Leaf Beetle

Here is the latest pest of interest that we are seeing wreaking havoc around town. It is called the viburnum leaf beetle. It is a beetle (another exotic that was discovered in Vermont only a few years ago) that feeds on the leaves of most species of viburnum, including the highbush cranberry. That bush is grown all over the place as a nice flowering ornamental bush. Well it doesn't look so darn nice these days. Many of the bushes we see along the road are totally defoliated/skeletonized. They will most likely releaf, but alas, this beetle has a second generation, which will emerge later this summer and nail it again. If you have one of those bushes and it hasn't gotten defoliated yet, wait a year or two and it will.

There are several things you as a home owner can do to protect your bush.

Learn to recognize the signs of the egg sites made by the female in the twigs and prune them off in the fall or early spring.
Inspect your bush in the spring and as soon as you start to see larvae feeding on the leaves, remove them by hand.
Use one of the pesticides registered against them.
If your bush was defoliated, when it releafs, continue to water it well. It has been stressed, and needs your loving care. No fertilizer is needed though. That would encourage succulent growth, which the beetles and the aphids would love. It would only stress the poor thing more.

The cultivated plants may be able to survive with vigilence on the part of homeowners, but it is really sad to think what this beetle will do to the native viburnum species that we like so much. There is lots of great information at this website:

http://www.cornell.edu/vlb/