Sawfly epidemic threaten threatens Colorado ponderosa pines

Evergreen forests in Colorado are getting a whole lot less green as scientists say sawfly wasps eating needles off ponderosa pines are expected to spread.

The Denver Post reports that the stout brown wasps have eaten needles off pines across 7,430 acres southeast of Denver.

Sawflies have multiplied around Colorado in recent years. A Colorado State Forest Service report says moderate to heavy loss of trees is expected this summer. The sawfly outbreak reached epidemic levels in July. Arial surveys showed defoliated ponderosa across 7,2000 acres in Elbert County. The flies have spread to Douglas County and El Paso County.

The sawfly outbreak is the latest in multiple insect epidemics in Colorado forests including mountain pine bark beetles and spruce beetles.