I have an absolutely beautiful Shagbark hickory on my property - very big, and very wide. every spring it gets large galls on the leaves and stems, and i loose large amounts of foliage. It doesn't seem to hurt the tree (at least not yet) but it does seem to harm nut production to an extent. There are some small bugs inside the nut when I bust one open, but I'm not convinced the gall and the insects are causing the gall. I live in Ohio up against the lake so we get milder winters. Does anyone have any suggestions on what these problems are and how I can get rid of them. (I get tired of raking leaves and picking up nuts all through the summer!)
Thanks

Reply to post by David Brunner, on November 07, 2001 at 09:45:52:

I don't know, for sure, about your tree's situation, but perhaps you can find information that is useful from the link below.

There is mention of a gall-forming fungus of twigs. Your tree may have more than one thing attacking it. I suggest you pay attention to the tree's water needs, as that is a basic stress factor.
Hopefully, someone else can offer you more information.

Reply to post by Mark Goodwin, on November 07, 2001 at 09:45:52:

The problem is a "petiol borer" or "rib gall" different names for the same problem.

There are some pesticide sprays that can be done to reduce the populations. As you have observed this is mostly an aesthetic problem. You need to decide if this has crossed an threshhold where aesthetics of your landscape are adversly effected.

As Mark says watering is important, the pest is a stress and drought can exascerbate this and then the tree can be harmed by a more agressive pest.

Reply to post by Mark Goodwin, on November 07, 2001 at 09:45:52:

Here is another link with more information about insects causing galls in hickory.

Reply to post by Mark Goodwin, on November 07, 2001 at 14:19:51:

And here's another...