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Photo courtesy USDA FOREST SERVICE
The NWTF's Role
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Beetles gone wild
In the mountains of the West, it's beginning to look a lot like Christmas — even in April. Dead reddish-orange trees now dot traditionally green pine forests and, on some hillsides, huge swaths display only a crimson cloak of death. The lingering white of winter snow completes the garish color scheme reminiscent of the December holiday.
The mountain pine beetle is killing trees by the thousands. Since the 1990s, this insect, measuring only 1⁄5-inch, has emerged as a major threat to western forests, watersheds and vistas. Wildlife winners and losers will emerge. Will the mountain-dwelling Merriam's turkeys be among them?
Recently, invasive species with no natural predators have been the culprits in ecological damage, but not in this case — a native has gone wild. Beetle outbreaks have occurred periodically, but the current outbreak has caused unprecedented damage.
Jared McJunkin, NWTF's conservation field supervisor in the Black Hills of South Dakota, says the current outbreak sweeping western forests signals trouble in forest health. Decades of fire suppression and reduced timber thinning have created homogenous, dog-hair-thick stands of trees — a beetle buffet.
Appetite for destruction
Tiny beetles kill giant trees by raiding their nutrients. They feed on the tree's sugars. The phloem, a kind of sugar pipeline, carries the tree's nutrients from the photosynthesizing needles down to the roots. When the beetles cut off the food supply, the tree dies. The insects typically target big, old, less vigorous trees with sickly root systems. Beetles seek bigger trees because the bigger the tree, the thicker the phloem. Healthy trees defend themselves by overwhelming the beetles with pitch.
Beetles can't flap their wings and fly like birds. More like flying squirrels, they sail to the next tree by drifting on the wind. Trees growing close together make it easy for beetles to infect the next tree. Eighty percent of the insects travel only 200 to 300 yards from the tree where they hatch.
Bringing down a 75-foot tall pine takes a coordinated attack by hundreds of thousands of beetles. Like teenagers texting their friends, the beetles alert other beetles through mass chemical communication, or pheromones.
Dead trees eventually fall, opening the forest. Sunlight, once blocked by the evergreen canopy, can now power the growth of grasses and forbs turkeys thrive on. If the dead trees burn, the fire can create wildlife-friendly mosaics of living trees and burned areas or create large openings for turkey-friendly early successional habitat. So, turkeys could be among the winners in post-beetle forests, as they were almost a decade ago in Colorado.
Rising from the ashes
The Hayman Fire, Colorado's largest wildland fire, raged for 20 days in June 2002 and burned 138,000 acres (about 215 square miles). The flames blackened large expanses, but fire didn't torch everything. Some trees and shrubs survived. When NWTF Colorado/Utah Biologist Stan Baker surveyed the devastation after reseeding, he recommended to the Colorado Division of Wildlife that they transplant turkeys on the blackened landscape.
"Fires have the potential to burn so hot that they scorch the soil, creating a biological desert for quite some time and leading to a longer recovery time," McJunkin said.
Will the beetles and potential forest fires end up friend or foe to Merriam's turkeys? No one knows the mountain turkeys' future. We need strategies to rein in the beetle outbreak and manage threats and changes to wildlife habitat. — Marilyn Stone