spotting round headed apple borers

windfall_rob(vt4)September 30, 2012

Round headed apple borers have become an increasing problem for me over the last 5 years or so.

We keep the orchard organic, which limits pretty heavily the solutions available to us for this particular pest....and it is a serious pest that can kill and or set back a young tree with just a few grubs.

I have not seen too many others on the forum complaining about them, so perhaps our pressure is high for some reason. But I thought I would throw out some observations for others to consider, and if any have suggestions I would love to hear them.

I have been painting the trunks white with various slurries. I don't believe it has much effect in deterring egg laying, but it does make it easier to spot the presence of the grub and dig them out.

Everything I have read suggests inspecting the trees mid-late summer, but I have never found them at this time, I think they are there but not readily visible. When I find them is this time of year, as the tree begins to shut down and usually a few days after the first good autumn rains. That's when the cambium seems to give one last push of fluid that floods the damaged areas under the bar. This in turn shows as a brown/purple stain on the white paint weeping through an egg slit. So now I do my inspections at the same time I install mouse guards for the winter.

The other thing I have noticed is that it is much harder to chase them down and dig them out when they are in the root flare...more nooks and crannies. When they are up a few inches on the trunk they are both easier to spot (less dirt and mulch stain on the paint) and easier to remove.

This makes me tempted to leave small screen "booties" on the lower 6" of the the trees all summer to force egg laying adults up off the root flare.

Thank you for reporting this comment. Undo


Excuse my ignorance, what are small screen "booties"? How do you use them - would you have pics?
(I just started reading this forum, do not have any experience growing fruit trees...just trying to learn something).

    Bookmark   September 30, 2012 at 10:07AM
Thank you for reporting this comment. Undo

"booties" is my own phrase, just the closest description to what I have in mind. A piece of window screen maybe 6" tall wrapped around the trunk where it meets the ground. It would have to be partially buried and tied snugly to the trunk at the top, or it would just make the problem the adults a nice sheltered place to lay their eggs.

It would be similar to the mouse/vole guard that many of us use in the winter, but much shorter. I suppose I could use the taller mouse guards all year but I worry about their trapping moisture and "hiding" other pest issues if used all year.

    Bookmark   September 30, 2012 at 12:43PM
Thank you for reporting this comment. Undo

At an Oregon fruit festival, I learned of a method where organic heirloom orchardists gather in thirds: manure, sand and clay - adding water and mixing until it is a thick slurry. They apply this to the whole truck up to a branch or two. They reapply (as needed?) every year. I haven't tried this method but they swear by it. Good luck to you in controlling the borers.

    Bookmark   September 30, 2012 at 3:48PM
Sign Up to comment
More Discussions
Source for Hidden Rose Apple?
Looking for a tree or scions but seem to be coming...
Fruit drop on Paw paw
Last year I pollinated by hand very thoroughly. I got...
Too new to this root acceptable?
I'm new to Orcharding and to GardenWeb (what an incredible...
mango seed it dead?
The Whole outside of it is black .. Is it dead? I looked...
Trisha Stewart
Converting typhoon damaged hillside forest to blueberry plantation
Hello all We've recently obtained a small strip of...
People viewed this after searching for:
© 2015 Houzz Inc. Houzz® The new way to design your home™