In Colorado, black-tusked tussock moths have spread across 25,000 acres in the last year from the 2014 infested area of 1,000 acres. The moth’s caterpillars are rapidly defoliating fir trees along Colorado’s Front Range, raising concerns for wildfire, recreation and tourism, and water supplies. Defoliated trees pose elevated wildfire risks and invite other pests, such as mountain pine beetles and western spruce budworm.
Since this infestation is occurring near the wildland-urban interface, it presents an even more serious threat to forest health; fir defoliation reduces wildfire resilience, accelerates sedimentation, and spoils aesthetics.
Colorado State Forester Mike Lester insisted on the importance of Colorado Springs’ urban forests in battling tussock moth invasion. He said, “Whether it’s for clean air, clean water, or the beauty, healthy forests are an important municipal asset.” Both the surrounding, rural forests and the city’s urban forests provide vital ecosystem services, but if the wildland forest have already been infested, the city's urban forests could be a final line of defense against the spread of the moths.
The U.S. Forest Service recently executed an aerial application of biological insecticide, acting under a 2014 Farm Bill provision, which grants a “categorical exclusion” from required environmental assessments and impact studies to fight insect invasions.