Well, someone is going to have to tell me why these aren't gypsy moth caterpillars. I know that they don't nest in conifers, but the older ones will migrate to them to feed.

That was my first thought rhizo, but on a spruce?!

Dan

Yes that is gypsy moth caterpillars, and they very often lay their eggs on Colorado spruce, especially if the spruce is near a woods, or on the dwarf grafted types in nicely maintained landscapes.

The tight branching pattern makes an excellent place to hide the egg masses, and I have seen 30 foot tall blue spruce completely defoliated by this pest in Ohio...not common but it does happen.

Certainly does happen. In fact, Penn State lists Picea pungens as "favored by older larvae but not by young larvae" host plant. Other conifers also listed include hemlock, pine and juniper.

Ken, you may want to do a walkabout.

tj

Interesting to know that they DO nest on conifers, not just move to them when mature. ;-)

Hate these things with a passion. One year we had an outbreak in PA so bad that the trees had NO leaves on them by August. Summer temps., but it looked liked the dead of winter. They WILL eat conifers, that much I know for sure. They ate everything in sight, in fact -- including grasses, wildflowers... everything! Our house was covered in the things... The roads were black with them... Really nasty!

And yes, they're definitely Gypsy Moth nasties.

Funny, the one at 12:00 looks like it has a pig's snout!
This is the first year in at least 3 years that I haven't had an infestation of these nasties in my yard. My witchhazel is finally able to leaf out beautifully for the first time since planting it four years ago. I hate them!

I've read they come in great numbers in cycles. Killing off the moths in summer helps, too, I think. I've scouted for the egg sacks, but have never spotted any. Also, checking for them when tiny (small and all black) helps. They seem to look different in every stage of their life.
Good luck Ken.

Ken, am curious...what did you do about the Gypsy caterpillars...and have you found any more on other plants? Oh, and how much damage did they do to the conifer?