Red-Headed Pine Sawfly Larvae

Subject: Strange caterpillar
Geographic location of the bug: Eastern Virginia
Date: 06/14/2020
Time: 07:55 PM EDT
Your letter to the bugman: Hello! I spotted a strange caterpillar at Weyanoke Bird and Wildlife Sanctuary in Norfolk,and pointed it out to my father. I got my phone out and snapped a few pictures of it. I guess my phone hit one of the branches and about 3 of them put their head back and exposed their chest that I saw was covered in spikes (They may have been sharp legs, but I couldn’t tell). They stayed like that for a bit until I backed away. I tried to find them on google, and I looked on a few bug Identification websites, but I saw none that looked like it. I was wondering if you knew what it was!
How you want your letter signed: Lydia Simon,age 13

Red Headed Pine Sawfly Larva

Dear Lydia,
Though they look very much like caterpillars, these are actually Red-Headed Pine Sawfly larvae, Neodiprion lecontei. Here is a BugGuide image for comparison. Sawflies are non-stinging relatives of bees and wasps. When larvae are numerous, they may defoliate trees. According to Featured Creatures: “After mating, female sawflies lay eggs in slits sawed in pine needles. Small larvae feed on outer needle tissues; larger larvae consume entire needles. Most species prefer older foliage, but all foliage is susceptible at end of growing season. Larval colonies may migrate from one tree to another, especially upon complete defoliation of the host tree or high feeding competition.”