The next time you drive up the Mount Evans Scenic and Historic Byway, the highest paved road in North America, be sure to stop at one of its most interesting, but least-known, attractions: a grove of remarkable trees whose gnarled trunks and knotty branches have stood here since the Roman Empire ended some 1,500 years ago.
Located about three miles above the Echo Lake entrance station at about 11,500 feet in elevation, the 160-acre Mount Goliath Natural Area protects one of the continent’s northernmost groves of Rocky Mountain bristlecone pines. These trees are known for their ability to survive in very harsh conditions for a very long time; the oldest known specimen, which is located near Craig, is believed to be at least 2,461 years old.
Rocky Mountain bristlecones are quite rare; in addition to one isolated population in northern Arizona, they are only found just below treeline in a narrow band from central Colorado to northern New Mexico. Somehow, despite the odds, these gnarled granddads prosper in some of the harshest environments on the planet, including strong, incessant winds, thin, dry soils, and temperatures that rarely rise above freezing.
These conditions, and the trees’ many adaptations to survive in this environment, are evident along a short, quarter-mile stroll along the natural area’s Bristlecone Pine Loop, where the trees range from about 700 to 1,600 years old. As you walk, it’s easy to see the bristlecones’ distinctive needles, which are bunched together in clusters of five, as well as the prickly cones for which they’re named.
To increase their chances of survival, Rocky Mountain bristlecone pines grow slowly, often adding only 1/100th of an inch in girth each summer and not adding any ring to their trunks during droughts. They typically grow between 9 and 25 feet tall. The wood contains a high proportion of resin, which can more easily resist disease and insects. And while most trees replace their needles each year, bristlecones save energy by using the same needles for decades at a time.
Because bristlecones can grow where no other trees can, this has saved them from the struggle for resources that plagues most plants. Recently, however, drier conditions and warmer temperatures have allowed mountain pine beetles to spread to bristlecones, according to a 2014 report. In addition, the rapid spread of white pine blister rust, a non-native fungus, across the state also has the potential to affect Rocky Mountain bristlecones.
During your visit, enjoy these remarkable trees and the beautiful alpine wildflowers in this natural area, but please tread carefully and try to reduce your impact so that these remarkable trees will remain here for another 1,500 years.