by ROSS CALVIN

The problem of discussing plant life becomes complicated, for some of those arriving in New Mexico may be compound microscope botanists, some collectors, others pathologists, still others geneticists. Some will be chemists or mathematicians, some others untrained in the ways of growing things and mainly interested in seeing while they tour. But one thing is fairly certainâ€"most visitors will come from a distance, so it may be useful to invite them to observe what they can readily see on the way hither, which will be a relatively painless method of amassing some information. (1)

Yet the method of arrival itself suggests choices, options, and exercises in probability. Do visitors come in covered wagons, or in jet planes; by bus, car, train, or some other way? The most convenient way, doubtless, is by plane traveling six hundred miles an hour at a height of some thirty thousand feet; but the most rewarding way is by saddle or on foot as the early collectors came. (2)

Since one cannot know his own country well if he knows no other, a visitor from the east arriving at an altitude of five miles will probably be more conscious than others of drastic changes in the landscape when he first looks down on New Mexico. Instead of the universal green of the east, he will note the earth as an unaccustomed tawny, reddish brown expanse, and this will be its common color through most months of the year. He will note the absence of rivers, but the presence of mountains which generally ring the horizon. He will wonder, after traversing the border counties at the western edge of the Great Plains, at the infrequency of plowlands, and will promptly conclude that New Mexico is one vast, bare desertâ€"an impression that will be corrected rapidly when he visits the dark National Forests where the slim, crowded spruces and firs tower skyward. (3)

The visitor from El Paso, as the Chihuahua desert (the name is fairly deserved) slides backward underneath him, will be amazed at the serpentine stripe of vivid verdure below, all completely leveled, and all marked off by geometrical lines and tightly bordered by pale hills where the vegetation is reduced to tiny dots not tall enough to cast a shadow. Still proceeding north, he will presently be above a ninety-mile stretch where the vegetation is so skimpy and the river so closely boxed in by desolate hills that Spanish explorers bestowed on it the sinister name Jornada del Muertoâ€"Dead Man’s Journey, which is self-explanatory. (4)

But on the other hand, a visitor descending into New Mexico from the northland in wintertime above this same Rio Grande will traverse a featureless jumble of peaks on which the black coniferous forest no longer 17shows as black at all but, snow- encased, gleams as white as the naked snowfields themselves. And he will find incredible the immense range of climate spanned in a flight only an hour long. (5)

The jet traveler approaching from the west beholds the greatest, most spectacular panorama of all, the true wasteland of the desert, with vast blocks uplifted from out of earth’s crust, plateaus dissected by giant empty canyons whose walls are seared to utter nudity by ages of the most intense sunshine on our continent. Here the architecture of nature is all designed on a gigantic scale, and the climate exhibits influences of a mighty ocean, of towering mountain chains, and the range of wandering planetary winds which created the desert. From the altitude of a cruising jet, the distances, the speed, the color, and the light are indescribably exhilarating. (6)

Since the traveler arriving from any direction can see for identification only a few species, it will suffice to point out only two of the harbingers of eastern New Mexico, both of which are dominant on that area of the Great Plains: the blue grama grass, which in fall and winter bears the graceful sickle-shaped head, and the small Yucca glauca which cannot be mistaken for anything else. (7)

Along the northern line, the visitor should look for the somber, almost black, forest of spruce and fir with its white patches of aspen on the 10,000-foot slopes. Descending farther southward, even a casual observer will note that these species give way first to the yellow pines, then to the junipers (“cedars”) and dwarf pines or piñons. The visitor arriving from the south will find most conspicuous of all the olive-green creosote bush in its summer-winter foliage, next, the omnipresent mesquite (Prosopis), then the various Opuntia cacti (chollas and prickly pears), and the yuccas. (8)

As he comes in from Arizona, the splendid saguaros will beckon him toward the gateway of New Mexico, but they will nowhere enter it themselves. The vase- shaped body of the ocotillo consisting of unbranching, ten-foot wands should be recognized at a glance, as likewise should the various yuccas and agaves. And in early springtime, a low tree with a rounded mass of golden bloom will joyously proclaim its identity as a paloverde. (9)

The desert plants thus enumerated can be recognized along various stretches of U.S. 66 as one holds his speed at a conservative ninety or, even better, at a conservative sixty. The amateur scientist will need to do some homework before he learns much systematic botany or plant physiology. It takes considerable study to comprehend the slow, age-long process which has resulted in the evolution of all this grotesque vegetation: the interaction of extreme aridity, high temperature, low humidity, high evaporation, infrequent precipitation, the hostility of numerous chemical solutions, and the natural rapacity of the animal population. Each plant must have an adaptation of its own, from the tiny winter annual, which must race through its course from a tender rosette to ripened seed before the searing sunshine arrives, on up through the series to the stoic saguaro, which seems able to scorn nature’s enmity.(10)

A final warning to the air traveler. He should be sure before deplaning that he has observed a bajada. It is a must. Bajada is one name, outwash slope is another, alluvial fan is still another. The stewardess should inquire of each student, and if his answer is “no,” she should reply, “Then you’ve just flunked the course.” A bajada is the most characteristic single feature of all in the sloping, stony topography of the desertâ€"and remember that the surface of the desert is regularly sloping and stony. The Spanish word itself means only a down slope, but it has come to have a semi technical senseâ€"a fan-shaped apron of rocky debris at the foot of a mountain where it has settled out of the summer torrents and there keeps accumulating in successive floods. As the mass builds up, the bigger fragments drop out closest to the parent crag, then the small ones, finally the coarse gravel, and lowest of all on the slope the fine sand. Thus the fragments are graduated in size, in distance traveled, and in the nature of soil resulting. As the fan increases in size and laps up higher and higher on the mountain’s flank, the geologists often describe the result by saying that the mountain “is burying itself under its own debris.” From the air, the lines of drainage will be seen to have assumed the form of a tree with its trunk downward, its branches high in air. But the most interesting aspect of a bajada is the nice proportion which nature works out between the plant species and their location on the curve. (11)