Guest Contributor – USDA

Visitors and locals alike to the Tongass National Forest can help scientists learn more about a familiar insect outbreak occurring in Southeast Alaska.

After a 30-year break, the western blackheaded budworm is back and causing the hemlock to turn reddish-brown.

Forest visitors can upload photos, video or information related to sightings of the insect or its damage to Alaska Forest Health Observations, a project in iNaturalist. More information on the project can be found at:

Reports have been coming in from the public of caterpillars hanging from branches and concern for the red-colored trees. Ground and aerial forest health surveys have confirmed increasing budworm activity in Southeast Alaska. Caterpillars feed on the buds and new growth of hemlock, and then tie needles together creating the red appearance.

In coming weeks, the budworms will turn into moths and Forest Service entomologists are looking for help tracking these insects to learn more about what next year’s budworm population may look like.

“People out on the forest can really help us improve our monitoring and be our eyes on the ground,” said Elizabeth Graham, Ph.D., an entomologist for the USDA Forest Service Alaska Region. “We use observations collected and shared with us by the public in our national reports on forest health.”

Some trees may not survive the damage caused by outbreaks. Those that do, may benefit in the long-term with increased light and a nutrient boost to the forest floor.

The last time a major outbreak in Southeast took place was from 1992 to 1995.

For more information visit:

For information about the Alaska Region, visit our media toolkit at: