Help! Caterpillar Infestation! - Ask Extension
Help! I just discovered all these worms eating my mugo pine! I’m not exactly sure what kind of worm they are. I didn’t see any tent that they came...
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Help! Caterpillar Infestation! #868853
Asked May 17, 2024, 11:00 AM EDT
Help! I just discovered all these worms eating my mugo pine! I’m not exactly sure what kind of worm they are. I didn’t see any tent that they came from.
My plan is to put on gloves and pick off as many as I can and put them in soapy water. Then I will spray the shrub with Bacillus thuringiensis? The shrub is small enough that I can cover it to keep the birds away.
Any help would be appreciated. Thank you,
Karen Davis
Ramsey County Minnesota
Expert Response
These are likely the larvae of European Sawflies. I'm attaching a response to a similar question; it should answer your concerns:
They feed on last year's needles and usually can be removed with a blast of water from a hose. They are short-term feeders - about 2 weeks - and only have one hatching per year (some insects like aphids have several generations per season). There are different kinds of sawflies that can affect other plants, but they can be hosed off as well. No need to remove the plant. Here is an excellent Extension publication about sawflies: http://www.extension.umn.edu/garden/insects/find/sawflies/. Scroll down to the Management section and you'll see different options for control. Again, blasting the insects with water or using insecticidal soap will help manage the populations (note: insecticidal soap will not harm pollinators).
They feed on last year's needles and usually can be removed with a blast of water from a hose. They are short-term feeders - about 2 weeks - and only have one hatching per year (some insects like aphids have several generations per season). There are different kinds of sawflies that can affect other plants, but they can be hosed off as well. No need to remove the plant. Here is an excellent Extension publication about sawflies: http://www.extension.umn.edu/garden/insects/find/sawflies/. Scroll down to the Management section and you'll see different options for control. Again, blasting the insects with water or using insecticidal soap will help manage the populations (note: insecticidal soap will not harm pollinators).
