SawflyThis pest problem is also a foliage feeder.  They look similar to the caterpillars in the larva stage which causes the plant injury. The adult in this case is a small wasp. Sawflies tend to feed in groups on the host plant. Sawfly’s generally tend to attack pines (mugo, black and Austrian) but can also attack white pine and spruce’s as well. A large sawfly population can kill back the ends of branches.