Hello, Thank you for your time. I have a large old shag bark hickory around my residence. In the spring of 98 I noticed that it was sparsely leafed compared to the hickory's in the timber about 100 yards away. I discovered that it had what I think you call galls. These galls were full of tiny winged insects. The tree looked bad. By summertime most of the leaves were falling as they died. Galls became black and crusty, etc... The tree came back well in spring of 99, not as many galls and fuller foilage. Presently the tree is completely full of leaves, and looks good and healthy from a distance. However, all the new green growth has the galls and tiny insects, worse than ever. Please help me to understand what is going on with the old shag bark. We really enjoy it and want to know if there is anything we can do. Thank you- CP

Reply to post by CP, on May 25, 2000 at 16:38:56:

It is called petiol borer. The company I used to work for found tat orthene sprayed when leaves are about .75 extended will give very good control. sounds like it may be a touch too late for you with that meathod tho. Once the galls become woody the product does not translocate well.

then tere are hight and product drift issues that weren't a problem a few years ago.

Call around for a local arborist and see if they have use a device called a wedgel, it is a trunck injection system that minimizes wounding of the tree. Other products. especialy Medcaps cause too large of a wound for my comfort.

Therte may even be some products that will work with soil injection.

Reply to post by jps, on May 25, 2000 at 16:38:56:

Alternatively: check to see if something like Merit is registered in your state for this problem. A good garden store or your local Coopertive Extension should know. That product is scattered on the soil, taken up by the roots, and ingested by the insect. It also has a long residual life.

Reply to post by Jerry, on May 25, 2000 at 18:27:17:

Thank You for your quick responses. I will check on your suggestions,ie. wedgel and the product "Merit". Spraying is probably not an option as the tree is close to 100ft. Also I do have children that inevitably play in and around the tree. Do you know the consequences of letting nature take its course. Is this tree's fate predictable if left untreated. One peculiar characteristic of this sturdy old shag bark is its hollow trunk at its base. Twenty five years ago a kid started a fire at it's base and damaged the tree significantly. Currently it has an opening like a tee-pee at it's base. It's sides have healed well, but you can see the dead wood on the inside, the scar tissue that is. Should I knock out this scar tissue and remove it? In light of its current petiole borer problem, I suspect this characteristic of the tree is the least of my worries. Thank You for your consideration of this tree and for the forum this site provides, what a great resource.

Reply to post by CP, on May 26, 2000 at 07:05:33:

The decay at the base is definitely a greater concern. The leafstem gall on hickories ususally do not cause significant harm to the tree. It will defoliate, but the trees usually respond the following year, or even with a second set of leaves the same year. Cultural treatments to keep the tree healthy usually suffice. Treatment is usually recommended in cases where aesthetics are highly important.

The cavity at the base should be checked now for progress of the decay. Although decay is usually rather slow in hickories, it could weaken the tree in just a few years, making it a high risk to leave near houses or play areas. I recommend you find a compentent arborist in your area to inspect it and advise you on how to proceed.

The American Society of Consulting Arborists can recommend highly qualified arborists and consultants in your area. Their web site and database is at
http://www.asca-consultants.org
or contact the main office at
American Society of Consulting Arborists
15245 Shady Grove Road
Suite 130
Rockville, MD 20850
(301) 947-0483

The International Society of Arboriculture maintains a current list of ISA Certified Arborists. The searchable list can be accessed at the ISA Web site, at:
http://www.isa-arbor.com