Part 4

Somewhat similar in appearance to desert chicory is WHITE TACKSTEM, one of the handsomest of the spring quickies. It is usually found on dry, rocky hillsides and has white or rose-colored flowers. Its name is derived from the presence of small glands which protrude in the manner of tiny tacks partially driven into the stems.

Following abnormally wet winters, FIDDLENECK covers patches of sandy or gravelly soil with a dense growth of bristly erect plants. These bear tight clusters of small yellow-orange blossoms arranged along a curling flower stem resembling the scroll end of a violin, hence the name. This plant, favored by the same growing conditions as creosotebush, frequently forms a dense though short-lived growth around the bases of those shrubs.

Associated with fiddleneck and creosotebush, SCORPIONWEED adds its violet-purple blooms to the spring flower display following winters of above-normal precipitation. The name is derived from the curling habit of the blossom heads, which may remind the observer of the flexed tail of a scorpion. Touching the plant may cause skin irritation in susceptible individuals. Unfortunately, scorpionweed is also widely known as wild-heliotrope, thus contributing to the confusion engendered by duplication of popular names. The plant properly called WILD-HELIOTROPE is similar in general appearance, but the flowers are white to pale purple and their odor is more pleasing than that of the scorpionweed. Wild-heliotrope, or “quailplant,” is another of the early spring ephemerals, but under favorable conditions, where soils are moist, it may continue to live and bloom throughout the year.

Growing in sandy locations and quite noticeable because of its large, yellow, showy, long-stemmed flower heads, the DESERT-MARIGOLD helps to open the spring blossoming season. Where moisture conditions are favorable, these plants may continue to bloom throughout the summer and well into autumn. Sometimes, during the hottest, driest time of the year, desert-marigolds are among the very few blossoms brightening the desert floor. Their bleached, papery petals persist for days after the flowers have faded, giving the plant the name paper-daisy.

One of the few species that makes a carpet of color in the monument is the tiny BLADDER-POD. This low-growing annual of the mustard family begins to cover open stretches of desert with a yellow blanket in late February or early March following wet winters. Bladder-pod is usually found in pure stands surrounding islands of cholla, creosotebush, and paloverde. It also mingles with other spring ephemerals, where it is promptly submerged by the ranker, taller-growing, more conspicuous annuals.

Illustrating one of the interesting phases in evolutionary variations among plants, the LUPINES are represented by several species which are able to survive and prosper in the desert. Some of the lupines are annuals of the quickie type; others are perennials with a life cycle of several years. Some of these longer-lived species join the ephemerals in the spring flower show, while others are more leisurely in approaching their blossoming time.

major plant communities of saguaro

Tucson Mountain Section Biotic Communities

Desert Scrub Grassland Transition

In any region where a great range of altitude exists, the vegetation grows in a continuum of overlapping but recognizable zones. Climate being the major controlling factor of this zonal distribution, the plants of each band grow higher on south-facing slopes than on cooler, moister north slopes. In Saguaro the major plant communities roughly correspond to altitudinal bands—with the desert at the lower, drier levels, and the transition through grasses and shrubland to forest community occurring with increasing altitude (and increasing rainfall). Timberline—the boundary between high mountain forests and the alpine meadows and barrens—does not exist in Saguaro, where trees clothe the highest peaks.

The fauna of each community is made up of animals adapted to the climatic conditions and the available food, cover, and water. In Saguaro, some animals, such as the desert kangaroo rat and the cactus wren, are restricted by their life requirements to a narrow belt; others, such as the gray fox and great horned owl, are more adaptable and live in all the major plant communities.

Rincon Mountain Section Biotic Communities

Desert Scrub Grassland Transition Oak Woodland Oak-Pine Woodland Ponderosa Pine Forest Douglas-fir Forest

plants of the hills and mountains

Most visitors to the monument see only a small part of it—the lowland cactus forests. But above the desert in the high back country of the Rincon Mountains is another world. These highlands are accessible only on foot or horseback; and they should remain so, for they are now in the last major roadless range in southern Arizona, and as such their wilderness value appreciates yearly. Interesting scenic trails reach the high places of the Tucson Mountains, too, but to see the greatest changes in plantlife you must climb the higher Rincons.

Oak-Pine Woodland

The thinning and final disappearance of saguaros along the trailside, although mesquite and ocotillos seem almost as numerous as on the floor of the desert, indicate that you are entering a slightly cooler, wetter environment. An occasional MEXICAN BLUE OAK or ARIZONA ROSEWOOD appears among the mesquites along the washes. The grasses that increasingly cover the ground as you climb include HAIRY, SIDEOATS, and SPRUCETOP GRAMA; CURLY MESQUITEGRASS; TANGLEHEAD; TEXAS BLUESTEM; and WOLFTAIL. Mingling with them are TURPENTINE-BUSH and shrubby SNAKEWEED.

A spectacular inhabitant of the grassland transition and open oak woodlands you are now entering is the AMOLE, or SHINDAGGER, whose rapidly growing blossom stalks attract attention from May to as late as August. The plants themselves, which grow crowded together in patches, consist of rosettes of succulent leaves superficially resembling bunches of flattened, green bananas. The stiff, needle-sharp leaf tips can inflict painful jabs on man and beast. During its lifetime, the plant stores food in its short, thick stem. Finally, after several years, it sends up an unbranched flower stalk that grows to 5 feet. The light-yellow flowers mature to brown, capsule-like fruits, after which the plant dies. The short stems or crowns, containing saponin, were used by Indians as soap. They also roasted the young bud stalks of some species by covering them with heated stones in pits.

Two noticeable plants of the lily family which sometimes dominate gravelly slopes of the grassland-oak woodland belt are the SOTOL and BEARGRASS, or sacahuista. The former grows from a compact crown as a dense, rather symmetrical cluster of long, thin ribbonlike leaves, usually grayed at the tips and armed along the margins with curved thorns. In early summer many small, cream-colored blossoms develop along the upper extremity of single fast-growing flower stalks 8 to 10 feet high. The bud stalks formerly were harvested and roasted by Indians. In Mexico a potent alcoholic drink, sotol, is distilled from the fermented juice of the pounded crowns. Sacahuista resembles huge, sprawling clusters of coarse grass. Flower stalks are short, producing conspicuous, open, loose sprays of small, tan-to-brownish flowers in May and June. Indians used the tender bud stalks for food and obtained fiber from the long, slender leaves, weaving them into baskets and mats.

Uncommon in the monument, but worthy of mention, are ARIZONA SYCAMORE and ARIZONA CYPRESS. The latter is restricted to the east flank of the Rincon Mountains, steep slopes, and deep canyons, where it grows with the SILVERLEAF, PALMER, EMORY, and NETLEAF OAKS; mesic shrubs; poison oak; and CALIFORNIA BUCKTHORN. Arizona sycamore grows along lower-canyon watercourses such as Chiminea and Rincon Creeks, which drain the rugged south flank of Mica Mountain and the west flank of Rincon Peak, respectively.

As you continue to climb, the open, grassy, shrub-dotted slopes change in places to sprawling thickets, called chaparral. These are made up of manzanita and skunkbush, SILKTASSEL, evergreen oaks, and underbrush of smaller shrubs. Among the common oaks are ARIZONA WHITE OAK and, on drier sites of the Tanque Verde range, SHRUB LIVE OAK. The oaks furnish protective cover, browse, and acorns for deer and other mammals and birds, and are of great value in retarding soil erosion on steep gravelly slopes.

POINTLEAF MANZANITA is especially abundant on the lower eastern flanks of the Rincon Mountains in the Happy Valley area. Early in spring the waxy, urn-shaped blossoms, the leathery, glossy, evergreen leaves, and the typical grotesquely crooked, red-barked limbs, make manzanita one of the most attractive shrubs of the chaparral.

Although SKUNKBUSH is a close relative of poison ivy and sumac, its aromatic foliage is harmless. Growing in compact thickets, skunkbush provides food and cover for birds and other small animals. Inconspicuous yellow flowers appear from March to June, and are followed by berrylike fruits which are dull red when mature.

As you follow the trail higher, occasional MEXICAN PINYON PINES and ALLIGATOR JUNIPERS appear. Gradually these evergreens become more abundant, mingling with the oaks to form a pigmy oak-pine-juniper forest. Clumps of MOUNTAIN-MAHOGANY are noticeable, their feathery seed “tails” gleaming in the sunshine.

Pinyons are among the commonest and most widespread trees of the middle elevations throughout the Southwest. The Mexican pinyon, which is the species growing abundantly in the Tanque Verde-Rincon upland, may be recognized by the fact that its foliage is in clusters of three needles to the bundle. Its cones require nearly 2 years to mature and contain hard-shelled seeds or nuts which are a source of food for many birds and mammals. These pines are usually shrubby, rarely more than 15 to 25 feet high, with horizontal, twisted, low-growing limbs. Intermingled with the pinyons are alligator junipers, often mistakenly called cedars. Those in the monument are conspicuous because their platy bark forms an attractive pattern resembling the squarish-scaled skin of alligators. The berrylike cones are soft and mealy, and are eaten by many kinds of wild animals.

Although the oak-pine woodland supports a heavy stand of shrubby trees over much of the terrain, there are numerous open glades and grassy hillsides. In addition to some of the aforementioned grasses, BLUEGRASS, BULLGRASS, and PLAINS LIVEGRASS provide ground cover in this belt. Following summer showers, many flowering herbs brighten the open slopes. Yellow to orange petals of PUCCOON, and the white to lavender-and-rose blossoms of MOCK-PENNYROYAL and HOUSTONIA are among those seen along the trailside.

Ponderosa Pine Forest

Just as grassland merges with oak woodland and chaparral, and these with oak-pine woodland, so you will notice, as you climb steadily higher, that these woodlands gradually mingle with the open pine forests that cover much of the Rincon Mountains above 6,000 feet. PONDEROSA PINE is the “big tree” of the Rincons, usually growing in clear, open stands. Through its high canopy of spreading branches, sunlight mottles the shaded forest floor. Its presence indicates still cooler and wetter conditions than those below. Here you will need blankets at night, though summer days are warm.

Except for grasses such as PINE DROPSEED, SCREWLEAF MUHLY, and MOUNTAIN MUHLY, ground cover is scarce. In tree-glades or on old burns, however, intermediate-type shrubs (such as BUCKBUSH) and various herbs have established themselves. Some herbs develop into patches of colorful flowers in summer and autumn. Common flowering plants found among the pines are COLOGANIA; PEAVINE, with its large and showy, white, sweetpea-like blossoms throughout the summer; lupines; DOGBANE; and the familiar white WESTERN YARROW. Here, too, may be found GROUNDSEL, ASTER, FLEABANE, and others, often brightened by the presence of butterflies and other insects seeking nectar and pollen. Most of these forest flowers bloom in late summer or autumn, when plants in the desert, far below, are drab and dormant.

Throughout the pine forests, numerous small canyons and rocky outcrops favor the development of thickets of oak and locust, frequently growing together. GAMBEL’S OAK, a leaf-shedding white oak, ranges in size from a small shrub to a handsome tree. It has broad, deeply lobed leaves which provide browse for deer. Its acorns are consumed by deer, rodents, and birds, including wild turkeys. The NEW MEXICAN LOCUST also is browsed by deer. Rarely reaching tree size, this species is an attractive vegetative cover because of its odd-pinnate leaves and large clusters of purplish-pink flowers that appear in May and June. Locusts sprout freely from roots and form expanding thickets which encroach upon oak clumps. They provide a valuable network of soil-holding roots, important in retarding erosion. The best stands occur along the east slopes of the Rincons.

Relatively few in number, compared with the stands of the dominant ponderosa pine, the smaller CHIHUAHUA PINE grows on lower dry slopes and benches. Its needles are shorter than those of the ponderosa pine, and its cones are conspicuously persistent, remaining on the tree for several years. This Mexican species invades the United States in the mountain ranges of southern Arizona and southwestern New Mexico. In the monument it is found mostly in the transition areas between oak-pine woodland and ponderosa pine forest.

The Rincon Mountains are not high enough to provide a fir-forest habitat except in a few favorable locations. On the highest parts of the Rincons, ponderosa pines dominate in the warmer, exposed locations, but whitebarked QUAKING ASPENS grow in pure stands on cooler slopes and with DOUGLAS-FIRS on the north side of Rincon Peak. West of Spud Rock are abundant small groves of MEXICAN WHITE PINE.

A cone-bearing tree growing with Douglas-fir—exclusively on higher northern and northeastern slopes of Mica Mountain—is the WHITE FIR. Flattened, gray-green needles curving upward from the branches, and large, green cones growing upright on limbs near the tops of the trees identify this beautiful evergreen. On open stands, limbs of even the large trees grow from the trunk almost down to the ground. The bark is gray or ash-colored.

BRACKEN forms a green ground cover in heavy stands of pine and fir. This fern grows 3 feet tall over much of the forested Rincon highland. Among the shrubs found on the mountaintop is the SNOWBERRY, whose leaves are browsed by deer and whose berries are eaten by birds and chipmunks.

A spring, a small mountain stream, and a meadow near Manning Camp complete the picture of the higher elevations in the monument. In this bit of meadowland are found BOXELDER, NEW MEXICAN ALDER, CINQUEFOIL, CHOKECHERRY, GOLDENROD, ORANGE SNEEZEWEED, MARIGOLD, WILLOW, and a number of other shrubs, grasses, and herbs characteristic of the high mountain meadows of the Southwest.

animals and how they survive

Just as plants depend for their existence on soil, water, and sunlight, so animals, including man, depend on plants. For green plants are the basic food producers in nature, manufacturing carbohydrates, proteins, and other essential compounds from minerals, air, and water, with the help of chlorophyll and the sun’s energy. Animals get their food either by eating green plants or by eating animals that have eaten plants. Microscopic decomposers complete this food chain, breaking down dead plants and animals into substances that once again can be used by plants. Since each link in the chain depends on the other links, it’s not hard to see that a change in one will cause a change in the others. And because animals depend on plants for cover as well as for food, their fortunes are doubly tied to the welfare of plants.

Animals and plants share some of the same basic problems—particularly, how to stay within tolerable temperature limits, and how to maintain an adequate supply of water. Plants solve these problems mostly by structural adaptations, animals mostly by behavioral. In the desert, for instance, cold-blooded animals such as snakes and lizards (which have no internal control over body temperature) crawl underground or into shade during the midday heat of summer, and come out to hunt food during the cooler hours. Birds and mammals cool themselves through evaporation of water from their bodies. This makes water conservation doubly critical for them; they too handle it by staying in the shade or going underground during hot times. Desert animals get much of their water from the plants and animals they eat, but some species, such as mule deer and Gambel’s quail, require large amounts of drinking water as well.

Cold weather poses another problem. Most reptiles and some mammals solve this one by hibernating underground or in rock dens, where temperatures remain moderate throughout the year. Many birds and some mammals migrate to areas where temperatures are warmer and food is more abundant, which may mean going farther south or simply moving down the mountainsides. And insects can survive in a dormant form, as eggs or pupae, though many species remain active during the temperate Sonoran winters.

If you want to see animals, then, go where the vegetation is thickest and most varied, and go when temperatures are moderate. During warm seasons in the desert, this means that walking the washes early or late in the day will give you the best chances for seeing wildlife. Coveys of Gambel’s quail explode into the air, peccaries snort through the underbrush, butterflies festoon flowering shrubs, and coyotes stealthily hunt.

Invertebrates

Insects are generally not bothered by excessive heat, and many species are active during the hottest hours. This is especially true when the plant blossoming season is at its height. Flowers of the mesquite, paloverde, catclaw, saguaro, and other desert plants are “alive” all through the day, as many species of insects seek nectar and pollen or prey on other insects attracted to the blossoms. Insects are fed upon by various species of birds; flycatchers flock to parts of the desert where nectar-yielding flowers are numerous. Because of the absence of extreme cold, the desert climate enables insects to be active throughout much of the year and to support a considerable bird population.

Insects play a far more important role in the plant and animal life of the desert than is usually realized. Many desert flowers must be insect pollinated to produce viable seeds. Birds of many kinds depend upon insects for food, and even the seed-eating birds, during the nesting season, rely upon insects to provide the enormous quantities of food and moisture required by their fast-growing nestlings. Many other desert creatures, including certain snakes and lizards and some spiders, depend upon insects for food. The body juices of the insects provide the all-important moisture—which these creatures can get from no other source. Bats, too, are insect eaters, spending the hours of darkness in seemingly aimless and erratic flight while foraging for moths and other night-flying insects that visit the light-colored blossoms of night-blooming plants.

Some species of insects may become so numerous that they threaten the very life of the plants on which they live. Pine bark beetles annually damage or kill numbers of pinyons and ponderosas in the Rincon Mountains, but have been kept sufficiently under control by their natural enemies so that their ravages have not reached epidemic proportions.

Among the common spectacular insects is the TARANTULA HAWK, a large blue-black, red-winged wasp that preys on large spiders. Temporarily paralyzing the spider with its sting, the wasp lays a single egg on its victim, thereby assuring an abundance of living food for its young. The PRAYING MANTIS is another large insect, usually green and inconspicuous among the foliage of desert plants, which it frequents in search of small insects. Ants of many species are active almost everywhere in the desert, harvesting seeds of various plants. Some species construct mazes of underground nest tunnels and deposit the excavated materials on the surface, forming conical, sometimes, craterlike, anthills.

Along with the insects, other arthropods (jointed-leg creatures with exoskeletons) find their home in the desert. The arachnids (eight-legged arthropods) include spiders and scorpions. Of the former, the NORTH AMERICAN TARANTULAS are famous for their large size and formidable appearance, which have given them the wholly undeserved reputation of being dangerous to humans. The really dangerous creatures are the SCORPIONS, whose long, flexible tails bear a poisonous stinger at the tip. Several species are found in the monument; but only the small, straw-colored scorpion has venom known to have been fatal to humans. The other scorpions found in the area can inflict painful stings, but with only localized and rarely serious effects.

Amphibians

As might be expected, amphibians are scarce in the monument because of lack of permanent water. The few springs and seeps, however, furnish excellent breeding places for several species of amphibians. Best known among these are the RED-SPOTTED TOAD, LEOPARD FROG, and CANYON TREEFROG, the latter common near Manning Camp. A spectacular desert amphibian and the second largest toad in the United States, is the huge COLORADO RIVER TOAD, sometimes found near residences in the evening when outdoor lights attract swarms of insects.

Reptiles