Arches National Park - Thorns and Thirsty Roots

Among these labyrinths of disintegrating stone, which rise like the bare ribs and knuckles of the earth, life is almost as stubborn and hard as the rock itself. Then, clear air envelops a land of extremes, shimmering beneath the summer's hot sun, shivering in the cold winter's white light.

The plants and creatures that flourish here and endowed with special qualities. Perhaps we attribute to them a character that is only a matter of natural selection and adaptation, but they seem more worthy of respect than plants that grow where soil is fertile, moisture is plentiful, and temperatures are benign. Each seems to outsmart the hard climate and stingy soil in its own way.

Some plants cling tenaciously to the rare damp places. Watercress, cattails, and marsh grasses survive around the edges of springs and in the few standing pools that endure along the beds of intermittent washes; when the streams flow, these plants soon inhabit them. In places where water seeps steadily through cracks and fissures in the Entrada Sandstone (places that may one day become the lower openings of infant pthole arches), maidenhair ferns, columbines, primroses, brilliant scarlet monkey flowers, and even wild orchids crowd together in hanging gardens. Here treefrogs live, and black-chinned hummingbirds hover, sipping the cool water and tasting the flowers' nectar.

Other plants survive on sandy flats because they have shallow, spreading roots that quickly soak up surface water after a brief shower, or long, fibrous roots that dig down to groundwater, no matter how deep. Nearly all have spines, needles, thorns, or other unpleasant protrusions that discourage browsing animals. Most bear very small leaves, diminishing the surface through which water can evaporate; and the leaf surfaces are usually hard or waxy to hold in moisture. Some drop their leaves in dry times and grow them back quickly when it rains. Cacti have no true leaves at all, but only hard spines that protect their stems, and fine hairs that gather morning dew.

Some survive by living quickly. In April and May of a good year, when rain does fall and temperatures are not yet killing, the park is carpeted by a colorful blend of bright wildflowers. Dozens of these plants, called, aptly enough, ephemerals, germinate, flower, and set seed like magic, almost overnight. The seeds may lie dormant for years until the right conditions return.

Pinyon pines, on the other hand, survive by living very slowly: they expend little moisture on unnecessary growth, conserving their energies for the long haul. A pinyon needs almost 200 years to reach full maturity, at which time it is a scraggly specimen about 20 feet tall. Many trees never reach such an age, however; the pinyon's worst enemy is the porcupine, which feeds on the moist inner bark, effectively banding a tree and cutting off its flow of nutrients. In company with the even more stunted Utah juniper, the pinyon forms scattered "pigmy forests" between fins and on rocky ridges and slopes. A juniper often looks more dead than alive, with a vital trunk growing from a mass of gnarled roots that have been exposed by erosion. The exquisitely sculptured forms of these twisted root masses, weathered to silvery gray, make the trees seem quite at home among the crafted rocks of Arches National Park.

Blackbrush, its still, spine-tipped branches sparsely covered by small, leathery leaves, is the principal plant that gives the open scrubland its scrubby character. It is joined by clumps of Mormon tea, with spindly greenish stems whose leaves are little more than scales, and by gray-green patches of perfumed sagebrush, its feathery branches bending with the western breezes.

Tough, woody, cliffroses sprout out of crevices in the cliffs and may stand up to 10 feet tall in open, rocky, soil. They are not much to look at most of the time, their leaves are tiny and their bark is a rough, scale brown, but in May each wears a glorious cloak of delicate white and yellow blossoms that brighten the landscape with airy specks of living sunlight.

Sand dunes, scattered in hummocky tracts about the park, are kept fairly stationary by the busy, meshing roots of buckwheat, fescue, ricegrass, sagebrush, and the fragrant and colorful little sand verbenas. Salt Valley is a broad swathe of mixed grasses. Cheatgrass, growing more than knee-high, is the most widespread; when pioneer cattlemen came into the area, the grass was so luxuriant that it could be cut and baled like hay. The slender, silvery stems caress the earth and etch lacy pictures against the sky; each pinhead-sized seed is encased in an almost white hull.