Thank you to the sponsors who support the Hill-McLennan IPM Program and Newsletter!

Van Poppel Crop Insurance
Ag Texas Farm Credit Services
Brazos Valley Equipment Co
LoneStar Ag Credit
Gerik Ag LLC
Helena Chemical Co

Weather Forecast

Jul 12, 2016

Emerald Ash Borer in Texas

Harrison County, TX is now under quarantine for the emerald ash borer, an invasive pest from Asia. This beetle is an extremely destructive pest of ash, and Harrison County is ground zero for its spread into Texas as of May 2016. Four beetles were found in monitoring traps near the Texas-Louisiana border, but no infested trees have been detected yet. EAB was first discovered in Michigan in 2002 and has decimated hundreds of millions of ash trees in 26 eastern states. Quarantined counties are not permitted to ship out any ash products, including wood chips, firewood, and nursery stock.

Photo by Stephen Ausmus, USDA-ARS

It's pretty amazing that four tiny beetles have caused such an uproar in a state as large as Texas. It's hard to imagine that our huge forests and beautiful parks could be so badly affected by such a minute insect. And here's the kicker: EAB have only been documented to fly a few miles from their origin tree. That means that the vast majority of their spread is due to the transportation of firewood from infested places. The cost of chemical control, economic losses from the sale of wood products, losses from forestry industries and nurseries, and the cost to remove and replace dead trees, is astronomical. Not to mention the loss of aesthetic beauty of our streets, yards, and parks.

The S-shaped galleries of emerald ash borer serve to distinguish it from all other borers attacking ash. Photo by M. Merchant, Texas A&M AgriLife. 
Photo by Mike Merchant. This tree shows bark flaking, which is caused by woodpeckers that feed on the borer grubs.

woodpecker bark flaking
Photo by Mike Merchant. These S-shaped galleries are characteristic of the borer larva, which disrupt the nutrient and water flow of the tree. It takes about 2-3 years for ash borer infestations to kill a tree, but all trees that are infested die eventually.

This map published by the USDA shows the current range of EAB in the US. Note that EAB detection depends on trapping and observation.

Check out the full story from Mike Merchant, Extension Urban Entomologist.
Also read his page on how to identify the damage caused by these beetles.

No comments:

Post a Comment