What Is Emerald Ash Borer? (And Why Does It Matter To Me?)

The Emerald 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 tens of millions of ash trees since it was discovered in Michigan in 2002.

The borer slowly destroys ash trees by infesting the layers that house a tree’s water and nutrients. It 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, once the borers are done feasting, they leave the whole tree to die and decay (not very polite pests, are they?) These dead and decaying trees are hazards to community members and their removal has a huge impact on a community’s budget.

Many community members are concerned about the threat that EAB poses to ash trees for the simple (and powerful!) reason that ash trees provide aesthetic value to our communities. In addition, it is estimated that landscaping, especially with trees, can increase property values as much as 20%. Mature trees clean the air, decrease storm water runoff, and reduce air conditioning and heating costs. It will take years for replanted trees to reach the size of the mature ash trees that are being killed by EAB.

How To Spot EAB

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:

  • Early-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

Resources About EAB In Wisconsin

Wisconsin Dept. of Agriculture – Facts About EAB: http://datcpservices.wisconsin.gov/eab/article.jsp?topicid=19

Confirmed EAB Finds in WI: http://datcpservices.wisconsin.gov/eab/articleassets/ConfirmedEABFindsInWisconsin.pdf

WI Firewood Quarantine Map: https://datcpservices.wisconsin.gov/eab/articleassets/Firewood%20Movement%20in%20Wisconsin.pdf

U.S. Department of Agriculture EAB Pest Alert: http://na.fs.fed.us/spfo/pubs/pest_al/eab/eab.pdf

National Emerald Ash Borer Information Network: http://www.emeraldashborer.info

Products For Protecting Your Ash Trees

What’s a Tree Professional to do in the face of Emerald ash borer? Take action now! Homeowners in Wisconsin can save their ash trees. The following products are scientifically backed and recommended for EAB prevention:

TREE-äge shows excellent 2 year control of Emerald Ash Borer compared to other treatment options and methods.