Knowledgebase
Tiger Moth #865460
Asked April 22, 2024, 2:59 PM EDT
Hi There,
We have property in Cripple Creek, CO. and found a dense silky white web in the top of our Douglas Fir. The tip of the tree is totally brown, and with binoculars I have spotted caterpillars on the outside of the web. I can't identify the caterpillar markings from where I'm at. I'm attaching a picture. We are trying to determine if it is a Tiger Moth or another species and if so, what needs to be done so it does not spread to the surrounding forest we own. If this is not the office to direct this question to and you know of the correct location, can you please let me know? Thank you so much!
Warmest,
Amy Lucitt
Teller County Colorado
Expert Response
Hi Amy,
It's tough to tell from the photograph; typically we'd need a sample of the insect or a good high-resolution photograph to identify them.
(I can say, though, that it looks like the photos might be of a pine--either a bristlecone or limber pine, perhaps, rather than a Douglas fir).
In any case, tent-making caterpillars in forest situations are usually only a problem for tree health if outbreaks occur over multiple years. In outbreaks, the tops of trees may be killed, as it appears may have happened in the pictured tree.
You do have some treatment options for key landscape trees; they are summarized at the bottom of this page: https://agsci.colostate.edu/agbio/ipm-pests/tent-caterpillars/
I hope this is helpful!
Cordially,
John
