Question
i have small green, black spotted caterpillars eating my mugo pines....they have already consumed one...before i noticed, them because they blend in....what can get rid of them? i live in Rhode Island

Answer
These are called pine sawflies. They are actually not real caterpillars but the lavae form of a fly. Caterpillars have legs all the way down it body where sawflies have sex legs near the front of the "caterpillar" looking insect. They are one of the insects that will eat pine needles. They can be controlled by spraying the foliage with an insecticide.
If only a small number of colonies are present and accessible, they can be handpicked, shaken off, or pruned from the tree and destroyed.

Some of the insecticides that can be used for sawfly control are listed below by the common name of the active ingredient (in parentheses) followed by an example brand name. Recognizing the pesticide common name allows you to find comparable products that contain the same active ingredient. Be sure to read the product label carefully before purchasing any pesticide.

(acephate) Orthene Turf, Tree & Ornamental Spray
(bifenthrin) Ortho Houseplant & Garden Insect Killer
(carbaryl) Sevin
(cyfluthrin)  Bayer Advanced Garden Multi-Insect Killer Concentrate
(esfenvalerate)  Ortho?Bug-B-Gon Garden & Landscape Insect Killer Concentrate
(imidacloprid) Bayer Advanced Garden Tree & Shrub Insect Control
(permethrin) Ortho Mosquito B Gon Tree, Shrub, and Lawn Spray