Re: What makes holes in walnut trees?

On 7/10/2025 10:48 PM, Michael Uplawski wrote:

bp@www.zefox.net wrote in rec.gardens:

>
http://www.zefox.net/~bp/walnut/

[snipped]

Anyway. No chemical product exists which could act against an
ongoing infestation. Usually you have to get rid of the beetle.

[more snipped]

There are actually two chemical methods of eliminating borers in trees.

One involves a drench of Imidacloprid.  The amount depends on the
diameter of the trunk at the height of your chest.  The drench is
applied in the root zone.  DO NOT use Imidacloprid while the tree or any
adjacent plant is blooming because it is very harmful to bees.  On the
other hand, it is harmless to birds and mammals; thus, nuts from the
tree would still be edible.

The other involves a small plastic capsule containing a systemic poison.
 I don't remember the name of the poison or the brand name of the
capsule, but a comprehensive plant nursery would know of this.  You
drill a spiral of 1-inch holes about 1-inch apart twice around the trunk
of the tree.  The capsules should just fit snugly into the holes.  You
then take a hammer and nail and gently puncture each capsule.  This was
very effective in eliminating ash white-fly from my ash tree and should
also be effective against any kind of borer.  However, I do not know if
resulting fruits and nuts remain edible.  Again, I would not use this
while the tree is in bloom because of bees.

--
David E. Ross
<http://www.rossde.com/

The stranger that sojourneth with you shall be
unto you as the home-born among you, and thou shalt
love him as thyself; for ye were strangers in the
land of Egypt: I am the LORD your God.
                         Leviticus 19:34