Several Weeks ago I saw these  hidden in, and eating, the needles of a Scotch pine. (I’m reasonably sure on the tree, if you know otherwise, say so)

Oct 12, 2012:

At first I thought there were only a few of the yellow-green spotted  larvae tucked into the pine needles. Each one has a sweet scent of pine, and they look like caterpillars.  However,  they are not , they are the Redheaded  pine sawfly (Neodiprion lecontei). Sawflies look like flies as adults and like caterpillars as larvae but they are neither flies nor moths and butterflies.  In fact they are in an order of insects more closely related to primitive wasps than anything else.  Unlike Wasps, they have a wide waist. Unlike true flies, adult  sawflies have two pairs of wings.

Why “sawfly”?  The females have a serrated ovipositor they use to saw a hole in a plant to lay eggs.  Most eat plants, and some, like this one, can kill a tree.

As I peered, I saw more and more. They reared up in unison, curving their backs and rearing their three pairs of legs, in the front. They, like caterpillars, cling with what look like extra legs- but they aren’t. Lacking joints, the extra stubs are called “pro-legs”. The rearing behavior is a defense mechanism.

Sawflies can kill a tree by eating all the needles if they do it a couple of years in a row. But these are unlikely to.  As I follow their progress ove rthe next week, they eventually eat about a sixth of the tree’s needles  and I knock them to the ground over a period of days-  calling it “Integrated Pest Management” each time.   Some I know will survive for next year.  Nice to see a new insect I has not noticed before, and to protect the little pine!