Hello bug people,
I’ve had a great time looking at your site and your link to Bug Guide, but I didn’t find a match for these guys that have devoured my red twig dogwood seemingly overnight! It is September 15 in Ionia, NY—-that’s way upstate, south of Rochester and northwest of Canandaigua Lake. Most of them are the white ones, but a few are the black with white stripes. In the 18 years we’ve lived here, nothing has ever eaten this bush. Do you know what they are? And are they two instars of the same caterpillar. Are they good or bad? Thanksverymuchly,
You will never find your fascinating creatures on a caterpillar page unless they have been misidentified. These are actually Dogwood Sawflies, Macremphytus tarsatus. When we saw your subject line, we thought you might be sending us an image of the Cimbex Sawfly, but we were nicely surprised as this is a new species for our site. According to BugGuide: “Young larvae are covered with a powdery white waxy coating. Mature larvae are yellow beneath with black spots or cross-stripes above.” The Natural Land Trust website has a nice page devoted to the Dogwood Sawfly. Sawflies are related to wasps.