When to use acecap for aphids on maple tree

Asked March 29, 2020, 12:17 PM EDT


I hope everyone is doing well as we try to get through the corona virus.

My large maple has had a problem with aphids the last 2 to 3 summers. I read that acecap works well with this. However, I'm not sure when to use the product. The directions say to "apply implants when wingless forms are first present." When exactly is that seasonally? Late spring, early summer?

Thanks for your help.

Prince George's County Maryland

3 Responses

We do not recommend acecap for several reasons. It can affect some beneficial caterpillars that feed on maples as well as cause damage to the tree when inserting the product in the trunk. They are not used that much anymore.
In general, aphids can be more of an issue earlier in the season before beneficial insects help to control them naturally.

You did not mention why this is a concern. Is the tree in poor health, branch dieback, etc. We need more information.
If the tree is overhanging a deck or over your car, perhaps you can prune or park the car elsewhere. Also, look for ants in the area around the trunk and in branches once the tree starts putting out foliage. Ants will protect the aphids because they like to feed on the honeydew that the aphids produce when they feed. It is possible you may be able to control the ants. Place outdoor ant baits around the base of the trunk. Also, if the tree is not huge, perhaps you can hose off the foliage with water.


Thanks for your response and I certainly don't want to hurt any bugs or my tree.

The honeydew does get on my cars and moving them is not an option. The biggest problem is that the honeydew attracts bees, wasps, and hornets. The bees are generally fine, the wasps and hornets are not. The tree is pretty big and I don't think hosing it off would make it a quarter of the way up through the leaves. I'll try though.

One other option, short of covering or periodically rinsing-off the cars, is to have a licensed pesticide applicator (such as through a landscape or tree care company) apply an insecticide to the tree via a basal trunk spray. Some insecticides are able to be absorbed in this manner, and would not require puncturing of the bark. Imidacloprid or Dinotefuran are two compounds that should manage the aphid population; the latter is the form that can be applied to bark.