Emerald Ash Borer

Emerald Ash Borer Adult BeetleEmerald ash borer (EAB), Agrilus planipennis, is an invasive wood boring beetle from Asia that is predicted to infest all unprotected ash trees in the United States and Canada over the next 20 years. Its population spreads very quickly and has already resulted in the death of 10’s of millions of ash trees since it was discovered in 2002.

So far, EAB has been found throughout the upper Midwest, East coast, and south to Louisiana and Georgia.

Emerald Ash Borer Infestations, Signs and Symptoms

Emerald ash borer lays its eggs on the bark of an ash tree and the larvae tunnel through the bark and begin consuming the sapwood of the tree. This feeding disrupts water flow to the canopy, dehydrating and killing that portion of the tree. Eventually, the whole tree will die.
D-Shaped Exit Holes Created by Emerald Ash Borer
Early infestations of emerald ash borer are nearly impossible to detect because the tree does not show outward symptoms at first. However as the infestation grows, the tree will decline and then die.

Emerald ash borer symptoms you will see as the infestation progresses:

  • Earlier-than-usual fall coloration
  • Dieback of branches with sparse foliage
  • New branches sprouting from the lower trunk
  • Woodpeckers feeding on infested trees
  • D-shaped exit holes
  • Decline in groups of ash trees all at the same time

See Emerald Ash Borer Lookalikes

How to Treat For Emerald Ash Borer

Tree Symptoms of Emerald Ash Borer
The treatment you should use for emerald ash borer depends on whether your tree is showing symptoms (therapeutic treatment) or is still healthy (preventative treatment). Regardless of the treatment strategy, watering after treatment is important.

Prevent emerald ash borer on healthy trees with Optrol – If your tree is important and valuable, and does not have a visible infestation, protecting it from emerald ash borer is smart, affordable and effective. Optrol is a professional strength insecticide for treating emerald ash borer that can be mixed with water and poured at the base of the tree. Annual treatments are required to maintain protection. This product can be applied from March through June or September through November, but the optimal treatment time is March through May. Start treatment for emerald ash borer when you are in a quarantined county and before symptoms appear.

See our video on How to Apply a Liquid Soil Drench – it’s not hard and it only takes 10 minutes.

Use Transtect for Therapeutic Emerald Ash Borer Treatments
For treatment in already infested areas, use Transtect – a fast moving insecticide that is applied to the soil at the base of the tree.

For the first year of treatment, treating infestations with Transtect will get insecticide into the tree very quickly and kill off the problem.

You can follow-up in subsequent years with a preventative treatment like Optrol.

More Information on Emerald Ash Borer

The Tree Geek is the premier source for information on emerald ash borer. Not only for homeowners in Minnesota, Illinois, Wisconsin, Michigan, Pennsylvania and Ohio, but all across the USA. Here’s some more stuff to check out:

Neighborhoods are gathering all over the country to protect their trees against the spread of emerald ash borer. Join the resistance and protect your ash tree today.

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