Was inspecting one of my trees (Black Cherry) last week:

http://tenacre.hostei.com/bcworms/black_cherry_2318.jpg

...and found some damage to the bark:

http://tenacre.hostei.com/bcworms/black_cherry_worms_2319.jpg

On closer inspection, I saw what looked like a worm or larva on the bark.

It was *not* tent caterpillar (I know all too well what those look like).

I sprayed the damaged area with a dilute solution of Tea Tree oil, and dozens of these larva(?) came out.

In my haste I neglected to take pictures, but if I saw a pic I could recognize it.

Anybody have any suggestions what these might be, so I could search for images on the 'net?