Spruce pest

Asked July 6, 2020, 4:29 PM EDT

I have a infestation of some sort on my spruce. Would appreciate any help you could give regarding what it is & how to treat. Thank you

Leelanau County Michigan

3 Responses

Hello,
May I have a picture a little farther back, so I can get a sense of how large this webbing is? Is it through the whole tree or just spotty? How long have you noticed it?

Thank you, I will watch for your reply and picture.

I first noticed it shortly before I emailed my question. I took out a few lower limbs around Memorial Day, but didn’t notice it then. It appears to be on the lower branches & as far up as I can see, through the limbs. Not terribly thick, but wanted to catch whatever it is early!

Thanks for the extra pictures. This appears to be spruce budworm, which leaves behind strands of webbing. I have asked an MSU entomologist for an opinion. When I receive a reply, I will post it here.

This pest can be managed on your landscape tree. In spring through early summer, monitor for the small caterpillar larvae and treat with Bt insecticide or other listed insecticide for caterpillars. Treatment is most successful when caterpillars are small. Take a close look at tips of webbed branches for caterpillars. Here is information and pictures of the pest on spruce-.

https://www.canr.msu.edu/news/scout_now_for_spruce_budworm_feeding_on_new_growth

https://extension.umn.edu/forest-pests-and-diseases/eastern-spruce-budworm#life-cycle-1268660