The Emerald Ash Borer is an import that is killing native Ash trees in the area. While not yet reported in Loudoun, Fairfax County is taking extensive precautions to try to contain the pest. Chris L. Jenkins of the Washington Post wrote an article titled “After Five-Year Absence, Destructive Beetle Discovered in Trees in Herndon, Newington“. According to Jenkins:
The emerald ash borer, a tiny exotic beetle responsible for killing at least 40 million ash trees from Michigan to Maryland, has reappeared in Fairfax County after a five-year hiatus, officials said yesterday. The insect — no more than one-half-inch long and one-eighth-inch wide — was found this week in 30 ash trees in Herndon and at least 10 in Newington. Fairfax and Prince George’s counties are believed to be the only Washington area jurisdictions that have been invaded by the beetle, which has burrowed its way through at least seven states since it appeared in southeastern Michigan in 2002.
State officials probably will destroy not only the infected ash trees but also those nearby. There are an estimated 2 million ash trees in Fairfax. Officials estimate that nationwide 30 million ash trees have died in six years.
The beetle has a cylindrical shape and metallic green sheen. Symptoms are a tree “dying from the top down” because the insects cut off the tree’s ability to distribute water. Sometimes ash trees push out sprouts from the trunk after the upper portions of the tree dies.
If you think you have an Ash tree that shows the signs of attack by the Emerald Ash Borer you should contact your local state forester (Loudoun County does not currently have one), Loudoun County Arborist Dana Malone (703-777-0397) or the local Cooperative Extension Office (703-777-0373).
Go to Washington Post Article for More >>>
How to identify the Emerald Ash Borer >>>
Other Resources:
Ash Tree Identification Bulletin
(PDF, 5.01MB)
Kimberly Rebek and Mary Wilson – criteria to properly identify ash trees.
Native Borers and Emerald Ash Borer Look-alikes
(PDF, 6.27MB)
February 2005 – Photos of insects that look like emerald ash borer.
Distinguishing Ash from other Common Trees
(PDF, 0.50MB)
This key is intended to help you distinguish between some common deciduous landscape trees frequently confused with ash, including: elm, boxelder, mountainash, walnut and hickory
Don’t be Fooled by Emerald Ash Borer Look-Alikes!
(PDF, 0.66MB)
Distinguish between these beetles that could be confused with emerald ash borer.
The most effective way to save your ash trees is to apply a systemic insecticide that provides long term protection against this, and other boring insects. Products containing imidacloprid (i.e. Bandit 2F or Merit 2F), a soil applied insecticide, have shown to be 100% effective in saving Ash trees in heavily infested areas of Michigan, Illinois, Indiana and Ohio. Imidacloprid is the active ingredient in Advantage Flea and Tick Control® for dogs, so pet safety should not be a concern, not to mention the fact that it is injected beneath the soil surface.
If preventative chemical treatments are not your thing, remember that healthy trees are much more likely to survive if attacked. Fertilization should be considered, especially for trees in the urban environment that do not benefit from nutrient cycling as fallen leaves are removed each fall. Lawn fertilizer is not effective as it is low nitrogen, contains phosphorous, and usually quick release. Trees need slow release high nitrogen fertilizer. Phosphourous is rarely deficient in soils in the DC area and has potential to leach out of soils and into the Bay.
As many people are going greener these days, organic and natural products are worth noting. Until biological controls are tested and become readily available, chemical treatment may be the only option. A foliar and bark spray of permethrin (i.e. Astro) is somewhat effective and natural. The only Registered Organic tree fertilizer on the market is sold by Bartlett Tree Experts and is called Boost Natural™. This fertilizer is phosphorous free and contains slow release nitrogen. It is injected beneath the soil surface to decrease the likelihood of runoff.
I am an ISA Certified Arborist and Maryland Tree Expert. I would be happy to answer any questions your readers may have about this relatively new pest.
Hi, I live in Boise, Idaho and our black walnut tree has borers. Last year we bought a liquid treatment from our local gardening store and poured it around the perimeter of the tree as instructed. We’ve heard that it takes 3 years sometimes to get rid of the borers. Our tree has leafed out, and it is showing signs that we didn’t get rid of them. Plus, I flushed out two of the holes with a hose and all this sawdust came out.
I would like to use a homemade remedy; is it true that mixing dishwashing soap (liquid) with water in a spraybottle and spraying that in the holes kills the borers? Do we need to purchase more of the commercially produced product? It is EXPENSIVE!
Thank you for your help in advance,
Kathleen
You should talk with a local forester about what works and what doesn’t. Although I am far from an expert on these matters, once a tree has an infestation it is generally on the decline and there is little you can do to save it. Chemicals can be a preventive measure but, as in the case of the Emerald Ash Borer, once they are in the tree there is no remedy. Try contacting a forester at the Idaho Dept of Lands Forestry Assistance Bureau at this link: http://www.idl.idaho.gov/bureau/forasst.htm