Crystal Lake Recreation Area, part of the Angeles National Forest and San Gabriel Mountains National Monument, will temporarily close this week as crews spray pesticides to prevent the spread of a destructive species of beetle.
The closure, announced by the U.S. Forest Service, will span from April 9-14. During that time, trees including ponderosa, Jeffrey/ponderosa pine hybrids and Coulter pines will be sprayed with an insecticide.
The insecticide, bifenthrin, will be used to prevent the spread of adult Western pine beetles. The beetles are set to soon migrate from dead trees in the recreation area to live ones, and will use those trees as hosts and killing them in the process.
The forest service says nearly 200 trees have been killed by drought and the Western pine beetle in the Crystal Lake area over the last several years.
The insecticide will be sprayed from the base of the trees up to 45-feet in the air.