Knowledgebase
Larvae on Leaves #868946
Asked May 17, 2024, 6:06 PM EDT
Here are some photos of our newly planted apple trees (first week in April). Now they are loaded with black caterpillars eating the leaves. They seem to be mostly on the underside of the leaves.
What kind of pest is this and what are your recommendations on how to treat as naturally as possible.
Eaton County Michigan
Expert Response
Hi Gordon,
Wow! That's quite a few caterpillars. I am unsure of the exact species, this doesn't look like any common apple pest.
I would recommend a Bt spray, which is an organic product which is broadly effective against caterpillars. I would continue to reapply as the label allows for the next month to reduce this population. Apple trees are hardy, but this much damage might take until next season to recover from.
Here's a resource on growing fruit at home: https://ecommons.cornell.edu/server/api/core/bitstreams/60165302-b299-433a-952d-9ac82cc63849/content.
Best wishes,
