Land, Water and People: Life above treeline: Colorado’s alpine life zone


Pam began to pick up her pace in anticipation of the view as we approached the crest of Copper Ridge. We soon reached the top where we both struggled to catch our breath, not just because of the 12,000 plus foot elevation, but because the views were, well, breathtaking.

An alpine meadow on top of the ridge extended to the northwest and southeast providing open views of the mountainous terrain surrounding us. We could see the spine of the La Garita Mountains above Creede to the north, and the high San Juan Mountains in the Weminuche Wilderness to the west, south and east. But, it wasn’t just the long, wide views that caught our breath, it was also the colorful bonanza of wildflowers that covered the ridge top.

Colorado is famous for its high country, especially the area above tree line, in what is called the alpine life zone. In our area, the alpine zone begins at about 12,000 feet in elevation, but it can vary depending on soils, moisture, and slope direction. It’s an area that can have hundred mile per hour winds, exceptionally cold temperatures, and a lot of moisture in the form of rain, sleet, hail, snow, and fog (clouds). It is also an area that can provide cool relief from the hot temperatures of lower elevations in the summer.

A large assortment of low growing plants make a life in the harsh conditions and short growing season of the alpine zone. Tiny blue forget-me-nots, white phlox and pink moss campion dot the tundra in June and early July, while white marsh marigolds and yellow buttercups pop up quickly below snowfields chasing their melting edges up the mountainside. Peak wildflower viewing hits about mid-July, with purple fringe, yellow alpine sunflowers, blue sky pilots, and paintbrushes that come in a wide assortment of colors covering the landscape.

The alpine zone also provides summer habitat for large ungulates such as deer, elk and bighorn sheep. Elk, in particular, will sometimes group up in large herds numbering in the hundreds as they graze in the lush, high meadows. Bighorn sheep are also found in herds grazing on alpine slopes generally not far from steep, rocky ledges where they can escape from predators, such a mountain lions. Some bighorn sheep herds will stay up on alpine windswept slopes through the winter.

It’s hard to walk very far in the alpine zone without hearing the loud, high pitched warning call of a yellow-bellied marmot. These close relatives to the woodchucks found in the Midwest and eastern U.S. are often seen sunning themselves on rocks in the cool mountain air. They fatten up all summer and autumn on grasses and forbs and then hibernate in deep burrows during the winter where they can lose up to half their weight during hibernation.

Several bird species spend time above tree line, but two in particular are closely associated with the alpine zone. Six inch tall brown-capped rosy finches spend their summers in the alpine nesting in protected areas on cliffs and rockslides, and feeding on seeds, insects and spiders. White-tailed ptarmigans spend summers and winter at or near the alpine zone. These grouse-like birds are streaked brown and grey in the summer and pure white in winter. I once sat quietly on a boulder watching a group of six or seven ptarmigans feed just 20 feet away. One of the plump birds didn’t eat, but seemed to act as a lookout as it moved from one rock to the next scanning the surroundings.

I pulled my camera out of my pack and began photographing the patches of tiny, ground-hugging forget-me-nots, phlox and moss campion. Pam wandered over to the edge of a steep drop off that overlooked Red Mountain Creek and sat down. I soon caught up and we pulled out dried fruit, nuts and jerky for lunch. As we sat there quietly taking in the view of Red and Piedra Mountains and South River Peak, pikas squeaked out their “eeeks” below while two ravens played in the thermals above.

Mike Blakeman is the public affairs officer for the Rio Grande National Forest.  He spends much of his free time scrambling around the mountains with a camera in his hand.

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