Sonoran Desert Plant Survival

Western genre films are about surviving against all odds, and that's exactly what the plants that live in the Sonoran Desert do. They've adapted to the desert's dry and hostile conditions by using three basic strategies: evaporation prevention, dormancy and symbiosis.

To prevent water from evaporating from the plant, creosote shrubs' leaves have a thick coating. Creosotes and triangle-leaf bursage plants shed their leaves entirely during a drought. With their dry, leafless stems and branches they appear dead, but they're only dormant and revive quickly following a good rainfall.

The tiny leaves of the palo verde trees help them conserve water because they provide just a little bit of surface through which water can evaporate. And no water evaporates from cacti because they don't have leaves: they store their water in their flesh. As they use up their water their flesh collapses inward like a squeezed accordion. Their flesh expands again after their roots soak up water.

The symbiotic protection of growing under a larger plant helps prevent seedling plants from being eaten by herbivores or trampled by animals and humans.