Life cycle of ponderosa pine needle miner. Research has shown that high-value trees can be protected against needle miners using either of two chemical control approaches. The more conventional is individual tree spraying with commercial hydraulic spray equipment. The other uses insecticide implants inserted into holes drilled into the tree trunk. Both are aimed at preventing establishment of the young larvae in green, uninfested needles.
Timing is highly critical in the case of the foliar spray.
In either case, some time is necessary before the trees' appearance will improve, as the old mined needles drop off. Treatments are summarized in Table 1. Treatments for ponderosa pine needle miners. USDA Forest Service Research Note RM-228, Rocky Mountain Forest and Range Experiment Station, Fort Collins, Colo., 1973. Stevens, Robert E., and David A. Leatherman.