This native insect is considered primarily a pest of ornamental pinyon, although it must surely occur in the forest, too. Susceptibility of pinyon trees to these and other needle mining insects varies from one individual tree to another. Some are rarely affected while others sustain lots of needle galls.
|Galls on pinyon needles caused |
by pinyon spindle gall midge
|Larva of a pinyon spindle gall midge |
in a pinyon needle