Sap-Sucking Insects, Gall Formers and Mites
FIELD GUIDE TO INSECTS AND DISEASES OF ARIZONA AND NEW MEXICO FORESTS
Gouty Pitch Midge
Cecidomyia piniinopis (Osten Sacken)

Host:  Ponderosa pine

Figure 75. Figure 75. Closeup of gouty pitch midge damage.

Symptoms/Signs:  The first signs of injury are noticeable in early summer when the new shoots start to droop, the foliage turns yellow and the shoot dies. Larvae are red in color and feed in pits under the bark of the current year’s shoots, causing twig deformities. Adult midges are small delicate flies, which resemble mosquitoes. They possess long antennae that are beaded in appearance along with a much reduced wing venation.

Biology:  The gouty pitch midge has one generation per year. Larvae overwinter in pits under the bark. In the spring, they make their way to the surface where they spin cocoons on needles.
Effects: Although yellowing and shoot death can be significant, these effects are not considered to be commercially important in most situations.

Similar Insects and Diseases:  Twig beetle (Pityophthorus spp.) feeding may cause similar death of small twigs and branches on pines. In addition, tip moths, ponderosa pitch nodule moths, and shoot feeding weevils (Magdalis spp) also cause flagging damage to shoots of young ponderosa pine.

References:  24, 46

Figure 76. Figure 76. Larva and pupa of gouty pitch midge.
Figure 77. Figure 77. Flagging damage to branches of ponderosa pine caused by gouty pitch midge.