At the northern end of the Chihuahuan Desert lies a mountain-ringed valley, the Tularosa Basin. Rising from the heart of this basin is one of the world’s great natural wonders—the glistening white sands of New Mexico. Great wave-like dunes of gypsum sand have engulfed 275 square miles of desert here and created the largest gypsum dune field in the world.
The dunes, brilliant and white, are every changing. They grow, crest, then slump but always advance. Slowly but relentlessly the sand, driven by strong southwest winds, covers everything in its path. Within the extremely harsh environment of the dune field, even plants and animals adapted to desert conditions struggle to survive. Only a few species of plants grow rapidly enough to survive burial by the moving dunes, but several types of small animals have evolved white colorations to camouflage them in the gypsum sand. White Sands National Monument preserves a major part of this gypsum dune field, along with the plants and animals that have adapted successfully to this constantly changing environment. (brochure)
Why don’t the fine-grained gypsum sand particles at White Sands disperse and blow away? Water! A shallow water table is the glue that holds the dunes together. Water, though just a few feet below the surface here, contains too many minerals to be drinkable, but keeps the sand moist and anchored.
The common mineral gypsum, hydrous calcium sulfate, is rarely found as sand because it is soluble in water. Rain and snow in the mountains dissolve gypsum from the rocks and carry it into the Tularosa Basin. Rivers would usually carry dissolved gypsum to the sea, but no river drains the Tularosa Basin. The water, with the gypsum and other sediments, is trapped in the basin.
The Soaptree yucca—New Mexico’s state flower—is one of only eight species of plants that grow on the shifting gypsum dunes. As a dune begins to bury the yucca, its stem grows rapidly to keep its leaves above the sand.
To most visitors of White Sands National Monument the glistening white sands stand out as the main attraction. Those who live and work daily in the park however have the unique privilege of seeing White Sands in its various moods and seasons: the colorful fall foliage, the dark and stormy monsoons, the cold blacks and grays of winter, and the abundance of life in the summer. White Sands National Monument offers infinite varieties of light, shadow, and color to those who have the time to sit and watch.
Photography is best in the low light of morning or evening. Photographing dunes can be tricky. The white dunes usually come out gray if exposed as a camera’s internal meter shows. With manual cameras, overexpose the photo by one or two stops to bring out the sand’s whiteness.
“Life is not obvious here. It is implied, or twice removed, and must be read in signs or code. Ripple marks tell of the wind’s way with individual sand grains. Footprints, mounds, and burrows bespeak the presence of mice, pocket gophers, and foxes.” (Rose Houk and Michael Collier)
“Nature uses only the longest threads to weave her patterns, so that each small piece of her fabric reveals the organization of the entire tapestry.” (Richard Feynman)
Thanks for tromping around the gypsum sand with me. I hope you weren’t too wind or sand blown in the 40’s temperature, wind gusting up to 30 mph.
Note: All information was transcribed from the White Sands National Monument brochure, placards, or postcards.
For additional White Sands National Monument images, go to http://www.corinthrose.com (under Travel)