THERE IS 4 OAK TREES ON THE BLOCK IN FRONT OF MY HOUSE, WHICH IS CITY PROPERTY. THEY ARE INFESTED WITH CATERPILLARS (BILLIONS OF THEM).
THEY ARE EVERYWHERE AND CLIMBING UP MY PORCH AND ARE TRYING TO MAKE WAY INSIDE MY HOUSE. THE TREES ARE ALMOST BARE OF FOLIAGE AND THEREFORE, SPRAYING BT WOULD NOT WORK. I CALLED THE CITY, THE MAYER AND THE COUNTY AGRICULTURE DEPT. TO NO AVAIL. MEAN WHILE MY SIDE WALKS ARE GREEN WITH DUNG AND CATERPILLARS ARE FALLING ON GUEST HEAD AS YOU GO OUT OF THE HOUSE. WHY IS THE CITY NOT CONCERNED THAT THESE CATERPILLARS ARE GOING TO SPREAD TO OTHER OAKS IN THE AREA?
DO YOU HAVE ANY SUGGESTIONS ON HOW TO CONTROL THE MASS NUMBERS OF CATERPILLARS. HELP

Reply to post by SUSIE CARR, on June 30, 2001 at 17:32:36:

I am not a pest control specialist. However, I have found, by reading, that some caterpillars only have one new generation per year in the north, but several further south. Also, though they can seriously weaken a tree by defoliation, the pest MAY not necessarily be so bad every year if left alone.
It may be that the town urban forester and tree maintenance are unaware of every pest outbreak, or they are economically limited in how they can respond. Have you talked with them?
I thought you might like to see the images at the following site, to see if your pest is among them.

Reply to post by Mark Goodwin, on June 30, 2001 at 17:32:36:

I'm not sure what kind of caterpillars you are refering to- there are many that may infest oaks. Most are only active for a rew weeks, and then they pupate and aren't seen until the next year.

If they are "they have attached themselfs to everything , my fence,cars,kids etc. etc", they are probably migrating from the trees to where they will pupate. This usually only lasts a couple of days, then they form the pupae.

Bear in mind that they will not harm anything but the tree- they eat the leaves, nothing else. the rest is nuisance- bad enough at times. Some people may be allergic to the hairs, and suffer a bit of itching or rashes.

Trying to control the pests now by spraying will probably not be effective. The caterpillars usually have to ingest the pesticides for it to be effective, and they don't eat once they start migrating. The best way to control the problem is to get a positive identification of the species of caterpillar, and find out when the eggs hatch in the spring. Then insecticide treatments can be applied by l icensed applicators to control the problem before it even becomes one.

Contact a local ISA Certified Arborist for help and advice on this problem. There are aseveral issues involved, including the health of the trees. Check your local phone directory for Certified Arborists that offer pest control, or check online. 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

Reply to post by Russ Carlson, on July 01, 2001 at 17:29:25:

I agree with Russ that pesticides are not effective. I am no expert here but if the caterpillar migrates to the ground during the day then returns to the tree to eat. Mechanical traps such as tanglefoot(provides a heavy duty fly paper)or burlap can be applied to the trunk to capture the insect. Hormone traps are simple enough to capture the male once it is in the butterfly/moth stage...this all depends on the type of insect that you are dealing with.

Reply to post by Andrew Wood-Gaines, on July 13, 2001 at 00:48:50:

Help--!! We live on 10acres of oak trees in Southern California, this is the first time we have seen caterpillars come out of the oak trees and strip the trees bare--most of the oaks are 50 to 100 years old on our property and I feel a need to help the trees! But even with the hundreds of birds, wasps/bees there are millions of caterpillars --we have at least 50 oak trees across our land and at this point the caterpillars have attacked and stripped 10 trees--does and one know if this will kill the trees? Can I help the trees in any way? We live in a valley covered with these beautiful trees--I have talked to people who have lived among these trees at least 30 years and have not seen caterpillars in the billions as we all are seeing? Does any one know --if we can help the trees?
Thanks for your time
Debbie