Mammoth Crest Loop
Inyo National Forest, California
WHITEBARK PINES have been fighting the good fight for a long time. Most of these gnarled trees are 600 to 700 years old—that’s a lot of time doing battle with the weather in the harshest high-elevation zones across the West. But though they can withstand the endless lashing of icy winds, whitebarks are practically defenseless against pests like pine beetles and fungi like blister rust. Unfortunately, both have reached epidemic levels thanks to recent warming trends, spurring die-offs from Washington to Wyoming. With no whitebarks, expect smaller plants and animals that use the trees for shelter or food (like Clark’s nutcrackers) to follow suit.
Some of the healthiest of the remaining whitebarks live in California’s southern Sierra, where the arid climate discourages pests. To wander among their wind-twisted limbs, head to Mammoth Lakes and follow the 13-mile Mammoth Crest Loop, which spends most of its time between 10,400 and 11,200 feet, where whitebarks still thrive. Start at the overnight lot on Lake George Road and climb for 6 miles along the crest of the Sierra, tenting in the rock-studded meadow between Lower and Middle Deer Lake. Next day, continue counterclockwise on unmaintained trail to Silver Divide and down to Barney and Skelton Lakes, just south of the trailhead.
TRAILHEAD Lake George (37.6035, -119.0112) SEASON
July to October PERMIT Required for backpacking (free for walk-ins, $10 + $5/person for reservations); obtain at the Mammoth Lakes Welcome Center. CONTACT www.fs.usda.gov.inyo
A hiker approaches Deer Lakes on the Mammoth Crest Loop.