Sotol

Agave Family Agavaceae

Another common name for sotol, desert spoon, comes from the enlarged bases of the long, serrated leaves. You can easily see them in dead plants that are falling apart. Sometimes these "spoons" are used in flower arrangements. The enlarged leaf bases clasp the stem in densely overlapping spirals. This arrangement produces the rosette of leaves so characteristic of plants in the agave family.

The tall, thick flowering stalks elongate in the late spring and bloom from May to August. Male and female flowers, borne on separate plants, are windpollinated. Each seed is contained within a papery, three-winged shell that, upon ripening, quickly disperses in the wind.

Sotol was once a plant of many uses. Native Americans stripped the leaves of thorns, then wove them into baskets, mats and thatch. When separated from their fleshy matrix, the fibers of the youngest leaves made good rope. The immature flowering stalks could be cooked and eaten, even distilled into an alcholic beverage. In parts of Mexico, a liquor known locally as sotol is still made. It has a strong taste and leaves a raspy feeling in the throat.

The common sotol of western Texas is another species, Dasylirion leio-phyllum Engelm. ex Trel. It differs in having the prickles on the leaf margin directed down instead of up.

Dasylirion wheeleri

Hopbush

Dodonaea angustifolia Soapberry Family

L. f. Sapindaceae

Hopbush flowers are inconspicuous, but the light, three-winged fruits, clustered at the branch tips, are not. Their resemblance to the fruits of cultivated hops gives this species its common name, but the two are not related, and hopbush cannot be used in making beer.

A farflung plant, hopbush grows wild in Colombia, Brazil, China, India, and many other places in the tropics and subtropics. Present in most Central American countries and nearly every state of Mexico, hopbush straggles north into Arizona and finally halts at the Mogollon Rim, where winters become too severe for this frost-tender species.

Part of its phenomenal success is due to its dependence upon wind for dispersal of pollen and seeds. Plants that rely on animals for these tasks don't always get good service: insect pollinators may be scarce in drought years, for instance. Wind seldom fails, and many species that rely on wind for pollination are widespread. Another reason for the success of hopbush is its preference for disturbance. Anywhere the seeds blow, they are likely to find habitats such as roadsides, old burns, and overgrazed ranges. The plants tolerate a variety of soil types, too.

Hopbush leaves are evergreen. A resinous substance makes them sticky and somewhat shiny. Underneath the resins is a waxy layer. This double coat of shellac makes the leaves resistant to water loss and no doubt deters many plant-eating insects, too.

Mexican mormon tea

Torr. Ephedraceae

The mormon teas are peculiar plants of ancient lineage. Like conifers (pine, Douglas fir, and spruce, for example) they bear cones instead of fruits, but that's where the resemblance ends. Mormon tea cones are flimsy, not stiff, and the plants are desert shrubs, not forest trees. Conifers produce abundant needles, which are modified leaves; the mormon teas bear neither needles nor leaves, only thin green stems.

Mexican mormon tea, a five-foot-tall shrub, is common on gravelly plains, rocky slopes, and even stable dunes. The green stems substitute for leaves in photosynthesis. Conifers rely on wind pollination. Abundant pollen, produced in male cones, is carried by the wind to female cones on other plants. Much pollen collects on the stems beneath the anthers and is wasted. Mexican mormon tea avoids this problem to some extent by the adroit design of its cones. The scales of the male cones are placed to create turbulent air currents so that when the pollen grains spill, they are swept away from the stems.

Mexican mormon tea can be found from western Arizona into western Texas. There are several other mormon teas in the Southwest deserts; all look much like this one. Torrey mormon tea (Ephedra torreyana S. Wats.) occurs in western Texas. In northern Arizona, southern Nevada, and adjacent California green mormon tea (Ephedra viridis Cov.) and boundary mormon tea (Ephedra nevadensis S. Wats.) are locally common.

Velvet ash

Velvet ash, a deciduous tree of streambeds and riverbanks, flowers early in the spring before the leaves unfold. That way, the pollen can drift from the male to the female flowers with as little interference as possible. The papery, flat fruits, which look like exclamation points, dangle in dense clusters at the stem tips until wind blows them away. Velvet ash leaves, like those of walnut, are divided into leaflets, five to nine per leaf. Walnut leaflets have toothed margins, while velvet ash leaflets are smooth.

Like other riparian trees of the desert, velvet ash is not adapted to an arid climate at all since the leaves have no mechanisms to prevent water loss. If the roots did not have access to permanent moisture, the trees would quickly die. The streamside habitat represents a final retreat for velvet ash and certain other riparian trees. Several million years ago, during the Tertiary epoch, the regional climate was substantially moister than it is now. Velvet ash, Fremont cotton-wood, netleaf hackberry, and Arizona sycamore belonged to a great deciduous forest that blanketed the valleys and hills. Now, forced to survive under much drier conditions, velvet ash is restricted to riversides and streambeds.

Velvet ash can be found from southern Nevada and Utah into Arizona, New Mexico, and western Texas.

One-seed juniper

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