It is dark green with a black head. They exist in colonies of 10-30 individuals that feed close together and move very little. Since they align themselves along the needles, it is difficult to see them especially in the early instars. This sawfly feeds on last year's growth. They can defoliate needles rapidly as they mature.
Hosts look sickly and growth is reduced.
Control with a host of materials such as sevin, diazinon, malathion or several restricted-use compounds. Spot spraying works if you only have a few trees ' but scout carefully to catch each colony. The blackened stems were beginning to turn orange from the characteristic salmon-colored spore masses on the infected stems. Beds with Volutella blight are thin. Many dead stems are present and many green stems have large blackened areas.