Pitch moth or sequoia pitch moth (Synanthedon sequoiae) larvae sometimes cause only relatively minor injury to the trees because they usually do not girdle the trunk. In other cases they kill the trees quickly. Larval feeding sometimes causes one or a few limbs to die or become weak enough to break. These insects produce copious amounts of resin. The most effective control of this insect is to only plant Afghan (Eldarica) pines in desert or xeriscape situations and don't irrigate after tree is established.
For more information about this moth, visit the U.S. Forest Service for their management guide.