Check trees for ash bore problems

If you happen to have one or two ash trees in your yard, you might have noticed that at this time of year, small roundish holes start showing up in the lower bark of the tree, usually located fairly close to the soil line but also found within the area going on up to seven to eight feet (and sometimes much higher in older trees).

This could be the sign of the Ash-Lilac bore, especially if you see small amounts of what looks like sawdust coming from the holes. Or in a worse case, you see limb die-back and/or the tree that has had ample rain but its leaves look droopy as if starved for water.

Either way, those "could" be warning signs that action needs to be taken, like spraying with an all-purpose insecticide having the chemical Permethrin as its main ingredient. (While the Ash-Lilac bore isn't listed on Permethrin's effectiveness against certain bugs, it still seems to be somewhat effective against this bore if applied at the right time.)

Or you could go another approach and use a systemic insecticide such as Bayer's that has the chemical Merit listed as its main ingredient.

While this product has been applied mostly during early spring, it “might” be more effective applying it in the fall and letting it slowly be absorbed by the tree over winter because its not very water-soluble and moves at such a slow pace to reach the tree's outer branches.

While the results of both of these methods are incomplete, its better than doing nothing. Bayer's has been fairly effective in this area, especially on smaller ash trees where you drench the ground right next to the trunk.

Timing is everything.

Using the spraying method, you spray in this area usually just before the end of April, before the bore larvae have a chance to hatch and enter the tree. Since the hatchings could be anywhere from late April up into the middle of June, its best to apply three sprayings approximately 10-14 days apart to provide complete coverage.

As if there aren't enough worries about this one particular bore, there's one even worse, the Emerald Ash Bore that's heading this way, coming from the Michigan area and spreading west-southwestward. It has devastated whole neighborhoods that had been over-planted with ash. So far, none of these bores have been found in Kansas.

Much of its spread has been caused by people, having leftover firewood and transporting the infected wood across state lines to their homes.

The Emerald Ash Bore is somewhat easier to treat using a systemic than the Ash-Lilac bore since its larvae does not burrow as deep into the wood.

In the past, there were many products that had the chemical Dursban listed amongst them. It was quite effective in treating the ash-lilac bore, even sometimes taking severely damage trees and eventually turning them into healthy ones. Unfortunately, the federal government banned its use several years ago.

WARNING – Even though Permethrin is not harmful to people or dogs, it is highly toxic to cats.

Barry Ragan is the volunteer forester for the city of St. John.