Confirmation of Emerald Ash Borer in Tarrant County, Texas
by Billy Cook, ISA Certified Arborist TX-1151A
As you may be aware from recent news stories we are dealing with a new invasive pest in our area. A native insect of Asia, Emerald Ash Borer has been positively identified in northwest Tarrant county.
Emerald Ash Borer (EAB) is a small shiny green colored boring insect that readily infests all species of Ash. Unlike many boring insects that we typically deal with that prey on weak or stressed trees, EAB is indiscriminate & attacks healthy and weak trees alike.
Infestation of Ash trees typically starts in the branches of the upper tree canopy. Decline and dieback of the upper canopy is one of the first signs of active infestation. The insect uses the tree as breeding ground, forming weaving galleries beneath the bark surface & destroying vascular tissue. As the young borers emerge from the tree they make tiny D-shaped exit holes in the bark. As the infestation grows within a tree, the disruption of the water and nutrient flow worsens, causing greater dieback throughout the crown. Abnormal amounts of leafy sprouts along the main branching structure and trunk typically begin to show up as well.
The Plan of Attack
If an infestation is caught early enough, treatment can be successful in saving a tree. Unfortunately, once a tree succumbs to 50% canopy loss, there is little hope of survival. Injection of a specific insecticide as a preventative measure is the best course of action for ultimate control. The proper injection treatment can be very beneficial in preventing and treating an infestation, but the treatment does requires numerous drill wounds to be made in the tree.
Currently, the Texas A&M Forest Service recommends that treatment be considered for Ash trees within 15 miles of a confirmed infestation. Overall careful evaluation and consideration of the surrounding area and trees should be taken into account when deciding when and where to make treatments. Taking into account the value and benefits that the subject Ash tree provides should play an important role in deciding whether or not to make treatments.
Routine monitoring by a knowledgeable Arborist is essential in managing EAB. Proper recommendations can be made for when and which trees should be considered for preventative treatments. The devastation that Emerald Ash Borer inflicts is apparent, and the insect is, without a doubt, on the move. The Texas Forest Service is performing monitoring projects and further updates on the movement of this pest will be likely.
Please be sure to let us know if you think you've spotted EAB in your landscape.
Posted: February 14, 2019