honey locust pod gall midge

Asked February 18, 2013, 9:50 AM EST

I live in the Colorado Front Range area and have five honey locust trees with varying degrees of twig damage from this midge. I know drought can cause more problems for these trees and I wnat to treat for midges this year. The information in the extension service is from 1988. This recommends pyrethroids (permethrin, bifenthrin),Spinosad, or imidacloprid during egglaying periods. I wonder if more recent work has been done on the insect, Oregon extension did some work on winter soil drenching they called "promising", but I can't find published results. Hope you can help. Thanks! Althea

Boulder County Colorado trees and shrubs insect issues horticulture

3 Responses

Dr Robin Rosetta at Oregon State Univ is currently on sabbatical.

The pyrethroids you mention, plus cyfluthrin, deltamethrin and lambda-cyhalothrin are treatment options, as are spinosad and carbaryl, applied to newest growth in May-early June.

Thank you. I wonder which of these options is the safest for pets and birds? I have small (9 pd.) dogs, and feed the birds under one tree. Thank you.

That's hard to answer due tothe use of different isomers of each active ingredient in differetn brand name products.
In general, pyrethroids (-thrin suffix) are toxic to fish and bees, but less so to birds and mammals.
Suggest you look at the NPIC (National Pesticide Information Center) data on each of the insecticides listed;
see http://npic.orst.edu/az.html#C

There is an entry on effects to birds, wildlife and pets for most insecticides