Sep 27 2019
Temperatures may be low but sun-exposure is extremely intense at high-elevations due to thinning of the atmosphere. UV radiation, which also causes cell and DNA damage in plants, becomes up to 10% stronger for every 1000 feet of elevation gain. Living in a treeless landscape at 10,000 feet or more above sea-level, and experiencing the unabated sun at twice it's normal intensity has selected for traits in most Alpine plants to protect against these direct impacts.
One of the most easily observable is the abundance of hairs found along the stems, among the flowers, and upon the surface of leaves. The pasqueflower specimen above exemplifies this pattern with a profusion of dense white hairs on nearly every observable portion of the plant. These hairs act directly to filter the solar radiation (similar to sunscreen), but they also serve as insulation by trapping heat and moisture—creating a micro-greenhouse on the surface of the plant.
Zoom in on the specimens below to take a close look at the hairs covering these Alpine species!
