These galls are composed of abruptly swollen terminal ends of twigs on Pinus edulis, which cause a large and conspicuous witches broom of needles to form on the swellings. The needles in the broom are arranged in a relatively circular structure, which is more visible when viewed from above. At the center of the group of needles are a group of stunted, dead needles with a few of them standing erect at the center of the group. These needles are positioned above a central, yellowish larval chamber, where the single inhabitant is found. Galls have been found in December through February in Utah and New Mexico.