I used to know the name for these worms but have forgotten. About five years ago I planted 250 austrian pines around my property. Three years ago I found small worms eating the needels. I used orthene to kill them and two or three days after I spray I check the trees for live worms. I cant find any liveing nor do any more needles turn brown the rest of the year. For the last two years I have sprayed while they were only a 1/8 inch long thinking they were all hatched and easy to kill but they come back the next spring. Rite now is the time I have to start looking for the hatch, is there any way to get rid of them for good?