Sunday, 9 May 2010

Explore the desert -- by Dick Grossman

This column from the Durango Herald is reprinted with the author's permission.

It’s spring and mud season at home. What a great time to explore the desert!

Utah is one of our favorite places for spring and fall. Often we head out with no specific destination in mind: I drive and my wife leafs through our tattered copy of Canyon Hiking Guide to the Colorado Plateau to find a route appropriate to our speed and time available.

Slickrock above Bluff UT: LAMountaineers
Now that we are in our sixties we have been concentrating on the area around Bluff. Recapture Lodge, a well-established motel there, is happy to house us and our dog. Last spring Gail drove while I slept off a busy night on call. After a long rest in a comfortable bed and a self-service breakfast, we were ready to clamber on slickrock.

Comb Ridge seen from 36000 feet: OK-Cleek
Comb Ridge, a few miles west of Bluff, is slickrock at its best. A monocline or upthrusting of sandstone layers, its overall angle is steep enough to be interesting but not too formidable to climb. Erosion has cut the ridge into a toothy comb shape and formed many canyons and irregularities that make clambering fun. The gritty sandstone provides good traction for scrambling on steep surfaces.

There are many places to explore, but few formal trails. We usually drive along the Butler Wash road, park and look for a way across the wash.
Comb Ridge and wash: Lynn Sessions
Typically we make a big loop, going to the top of one of the teeth of the comb. The views there are amazing and the drop of a thousand feet to Comb Wash is breath taking. We descend by another route. Part of the challenge of these hikes is not getting trapped by too tall a drop-off. Another challenge is finding the car on the way back. It has a way of disappearing in the terrain’s creases.

About the only signs of human habitation are Ancestral Puebloan ruins and rock art. It is a mystery why these people abandoned the Four Corners region. One widely held theory is that they used up the resources—killed the deer, cut down all the trees, harvested the edible plants. Food was so scarce that they turned to violence and raiding neighbors. In any case, the survivors moved on to another, unspoiled area.
cryptobiotic soil: by gardengeek
We are careful to avoid walking on cryptobiotic soil. This biological frosting appears dark and irregular, as opposed to the smooth surface of blown sand. A delicate mixture of cyanobacteria (blue-green algae), mosses, lichens and other living things, it helps stabilize the sandy soil that would otherwise erode from the wind and rare rain. Close to the bottom of the Ridge the hooves of careless cattle have destroyed most of this coating.

When we are lucky to be in the desert shortly after rain, we delight in finding the moss green. Brown when dry, it takes just a few seconds after water hits for this simple plant to turn green. If you don’t believe me, try giving some dry moss a drink.

We like to examine the potholes that collect what meager precipitation may fall. We kneel down beside the pools to search for their miniature animal life—insect larvae, diving beetles, or many segmented copepods. Many species that live in the desert are specially adapted to their dry environment. For instance, the tadpoles of rapidly developing spadefoot toads may swim in some of the larger puddles

These amphibians go through their life cycle unusually rapidly because water doesn’t last long in the desert. The adult toads burrow down in sand and wait for rain. They sense precipitation not by its moisture but by the vibrations it makes when it hits the ground, and by the associated thunder. The spadefoots emerge from as far as a meter underground and mate in the transient puddles. Their eggs and tadpoles must develop into adults quickly before the pools dry up.

Most of all, I love the pothole gardens that form when plants grow in depressions filled with sand and organic matter. Some are tiny, with just one plant or stunted tree. Others contain complete ecosystems with a selection of plants and maybe a mouse burrow. These gardens hold a mystery for me, that apparently has never been studied scientifically. Do they obey the biological rule that the number of species on an island varies with the island’s size?
Comb Ridge after rain:

We are fortunate to have so huge an area of varied desert to explore so close to home. Although it may appear barren at first, the desert contains much diversity and some unsolved mysteries.

Los Alamos Mountaineers, Upper Ticaboo and Bluff Explorations
Lynn Sessions, Comb Ridge and the Posey Trail
Ned Eddins Hole in the Rock Comb Ridge (5 posts) Cryptobiotic Soil
The Anasazi in Wikipedia; and climate change, Scientific American 5 Oct 01

1 comment:

fdmillar said...

Recent scientific research suggests the Anasazi ecosystem was wiped out by climate change. SciAm (5 Oct 2001)