Emerald Ash Borer

What is Emerald Ash Borer (EAB)?
Emerald Ash Borer is a beetle native to East Asia. It was identified in the US in 2002. Adult beetles lay their eggs in the bark of ash trees, and the larvae then eat the inner bark, killing the tree. It's already killed millions of ash across the US, especially in the Midwest.
Emerald ash borers will kill your ash, unless you treat it with insecticides.
Emerald ash borers have been found in Colorado, South Dakota, and Nebraska. We can't stop them, but we can slow them down. This gives other trees more time to grow, and makes the effects on our city canopy less devastating.

Why should we care about EAB?
Ash is very common street tree! Ashes compose about 20% of our city's canopy.
Ashes provide energy savings, runoff control, and mitigate air pollution. They also increase property values and provide shade.

Symptoms of emerald ash borer:
Epicormic shoots. Young material growing off the trunk or at the base of the tree. This may also be a result of pruning, or a stressed tree.
Canopy decline. Lean against the trunk of the tree, and look up – can you see large patches of sky? This may also be a result of a stressed tree, or of other ash borers.
Roughly 'D' shaped, irregular exit holes about 1/8th of an inch across. Other borers make larger, rounder holes, or much smaller ones.
S-shaped tunnels under the bark. Other borers go much deeper, or do not meander as much.
Vertical splits in the bark. These are especially prominent in smaller ashes.
Lost bark or woodpeckers:
Woodpeckers like to feed on EAB larva. If you notice more woodpeckers than usual, or your tree is losing its bark, take a closer look.

What can you do?
Don't move firewood off the site where you cut it! EAB can go undetected for years, and moving firewood is the surest way to hasten its arrival in healthy trees.
Plant diverse trees, including trees which are not commonly planted in Sheridan. EAB is devastating because many street trees are ashes.
Consider cutting down ash trees that you are not interested in saving now. They will need to be cut down eventually, and if you remove them now, you can plant something else sooner.
Check out your ash. If they look like they have several symptoms of EAB, contact Clark Van Hoosier, the city of Sheridan’s certified arborist, at 307-655-8297, or email him at cvanhoosier@sheridanwy.net.

Once it's identified within 15 miles of Sheridan:
Treat or cut down your ash trees.
Treating ashes with insecticides is very effective, but expensive (~$200 every year, depending on the size of the tree). Even if a tree is infected, insecticides can kill the borers that are in the tree, but once it is past a certain point (roughly 30% canopy decline) treatment is no longer likely to succeed.

More information:
See Trees for Sheridan for a list of recommended trees.
See EAB Management Guide for a more detailed picture of what to do once EAB reaches Sheridan.
See Ash ID for a detailed ash identification sheet.
See Ash Pest Guide for a more detailed pest identification sheet.

City of Sheridan

Pest Facts