The Emerald Ash Borer is a non-native pest that entered the United States in the early 2000’s. Since then it has spread through several states, including Maryland and Virginia. From my observations in both Fairfax and Loudoun County, this pernicious beetle is well-established and active in destroying native species of Ash trees. Most commonly we see Green Ash (Fraxinus pennsylvanica) and White Ash (Fraxinus americana) in our area. The beetle is a striking bright green color, and the adult insect is aptly names “emerald”. However attractive, the life cycle of this insect includes a larval stage boring through the bark and wood of ash trees, and it is this aspect of the insect that is killing trees. I have seen many local trees in commercial and residential sites with severe dieback, decline, and even outright death. Once a tree is infested, it may take 2-3 years before it begins to show obvious symptoms. Treatment with systemic insecticide after the borers have begun colonizing a tree can slow the decline, but is unlikely to completely control the problem.
The best control method is prevention. If a home or business owner has Ash trees on their property, or needs help identifying a tree, it would be a proactive approach to have a professional horticulturist or arborist take a look to see if there is any current infestation. If trees are showing signs of several years’ damage, it may be best to remove the tree and replace with a different species. If an Ash tree is not yet having issues, a professional can treat aggressively with a systemic insecticide, usually in the form of a soil drench. This type of product can provide protection to a valuable ornamental tree for a given length of time, which can vary depending on the formulation of the insecticide. Typically trees become infected in May or June. By this point in the summer it is usually very clear from the D-shaped exit holes of the adult beetles whether a tree has been attacked. If you are curious about more information on how to identify the pest or the ash trees, take a look at several links below. Campers and outdoors enthusiasts should be especially respectful of quarantines and park rules regarding bringing firewood into a forest from the outside areas. That is one major way that the Emerald Ash borer has been able to so quickly colonize so many areas.
For anyone that may suspect they own a tree at risk, contact a horticulturist at Sunrise Landscape + Design for a consultation that can determine whether the Emerald Ash borer, or any other emerging pest, may affect your landscape in the near future. We can identify the trees, detect the presence of the pest, and assess the situation to suggest your best option for managing any risks.
Here are some good articles to read to get more information.
UPDATE: There is a quarantine of EAB trees in Virginia
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