Before going more toxic, try hard streams of water from a hose nozzle, directed right at the bugs. It can do a lot. Also, insecticidal soap works wonders on soft-bodied insects.

+oM

there is a pest forum ... those peeps are pretty good .... and dont necessarly visit here ....

otherwise ....DO NOT DO ANYTHING BEYOND THE WATER... UNTIL YOU PROPERLY ID THE PROBLEM....

down here in adrian ... we are in week 10 to 12 of extreme sever drought .... nearly every tree on my 5 acres ... has yellowing leaves... looks wilted ... and all are stressed ...

you can not convince me.. that the bug is adding anything to that equation ... by what you describe alone ..

also ... admit it.. the garden season is ending ... it will be september by monday ... within a month.. your trees will be neked .... again .. late season.. plus drought ...

but bottom line ... nearly NEVER do bugs kill a tree ... and frankly ... at this time of year.. its a waste of money ... and harmful to mother nature to waste time and $$$ on chemicals ....

the only proper recommendation... this late in the season.. would be a quick call to your local extension office... and perhaps a visit with a specimen ... to properly ID the problem .... IMHO ....

spraying it down with a good blast of the hose... will cause no harm ... help alleviate the drought ... and probably reduce the population ....

i suspect an aphid.. which give off honeydew .... which ants 'milk' .. so dont freak out if you see ants also ...

i highly doubt you will lose a tree ... nor will there be any problem next year .. plagues come.. plagues go ... and our darn cold winters take care of most population explosions... recall the imported ladybug plague of a few years back... it drove us insane that fall .. and a bit the following spring.. and i havent seen more than a few in the years since ...

where are you in MI?

good luck

ken

Might they be Boxelder Bug nymphs?

Here is a link that might be useful: {{gwi:424629}}

Ken: I am North of you in Genesee county. Thanks to all of you who took the time to reply. I will start with the stream of water, I have done that in the past with some success and wait for the cooler weather provided by Mother Nature to help. This is the second year I have had these pests, though this year they are much worse and have spread to additional trees. They are also moving up higher in the original tree. Next spring I will try insecticidal soap or maybe Rotenone if the spraying is not sufficient. Thanks again. Paul

Paul, since you had the same problem last year, and it is worse this year, it sounds as though whatever it is is overwintering under your trees. Proper ID will also give you some idea of what you can do to limit the population for next year - whether raking up and burning/bagging leaves, to banding the trees in the early spring with Tangle-Foot or an equivalent, to a possible soil treatment or, least desirable, but sometimes the only option, and the more expensive, using a systemic pesticide to break the cycle....

As was already suggested, you might be seeing box elder bugs. If so, they are often appear annually in the fall but don't damage trees.

Can you post a photo or two?

your thoughts as to what to use next year.. are inappropriate.. until you ID the bug ...

put a few in a baggie and visit the county extension office ....

i dont care if its organic or not.. treatment is a waste of time and money .. if its not going to work on the bug... or if the bug isnt even a threat ...

you havent really even found out.. if the leaf loss is drought related .. or related to the bug ....

ken

Again I value all of your input. Didbit I did just leave the leaves to compost under the trees because they are small leaves and were easily chopped up with mowing. This fall I will rake and dispose of them. After doing some research with books I believe the bugs are some kind of an Aphid. They did attract ants in the spring and now are attracting bees. THere are many different types of aphids and these are larger than the ones you would find on garden plants. I am sure they are causing the leaf loss because from a distance I can tell what branches they have infested by looking for the yellow or missing leaves. I will also try to get to my extension office for a proper ID and ask for their input.