Wednesday, March 30, 2016

They're Everywhere, They're Everywhere!

The U.S. Department of Agriculture has published a new map showing the known distribution of Emerald Ash Borer (EAB).  I think it is safe to say that the bugs are between the dots on the map showing trapped beetle locations, and if you believe that there aren't any between St. Louis and Kansas City you should not talk to any bridge salesmen.

The mapping was done with traps like these over a period of several years.  It's a pretty good method, catching bugs with a sticky substance, but I have been critical of the application.  The adult borers are active in April and May, but the traps are not picked up until Fall, so bugs have lots of time to be destroyed by the elements.  The traps are placed and picked up by student interns from the University of Illinois and for a few years the researchers have been saying that it appeared the bugs were centered along the Interstate highways.  I have seen a lot of these traps that were not picked up by the Fall interns, but the people running the program in Champaign don't know where the pickup crews don't go.  I saw good evidence of EAB just a stone's throw from an uncollected trap a few years ago, and that spot is still not on the map.  Anyhow, these are beetles with wings, with an abundant food supply, so you can bet they have spread.  An expert in EAB told me recently that we can expect to see the big ash die-off begin in Southern Illinois this year, and I think that is good information.

The Illinois Department of Ag posted one of these signs with every trap, and it educated the people who were curious enough to stop and look.

This is an Emerald Ash Borer, in a collage by the Forest Service.   This picture shows the insect (a Buprestid beetle), ash bark, the larval galleries, and ash crowns in the process of dying.

I have yet to see one of the little blighters in the wild.  Folks call me and want me to look at the brightly colored insects they have found, like this native Buprestid beetle,

and this Six-Spotted Tiger Beetle. These little critters are wild-goose-chases for me and they cause many interruptions.  Take a picture and send it to me, or call the University, or the IL Dept. of Ag.  There will be plenty of the real EAB beetles in April and May this year, and we should expect to see ash trees dying from the top down.

There is nothing that can be done on a large scale, though you may be able to save important individual shade trees by injecting them with insecticides to kill the larvae.  There are a few contractors in Southern Illinois who are equipped to do that in the Mt.Vernon-Marion area.  EAB is not going away, and you will have to inject a tree every other year to maintain it.  Whether or not that is worth the money will have to be up to the individual owners.

See images of EAB HERE.

Forest Service info HERE.

Emerald Ash Borer Poster HERE.

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