Fouquieria splendens (ocotillo)

Ocotillo is an unusual species with a remarkably wide range across the entire Sonoran Desert and into the Chihuahuan Desert. It is one of only a few woody species that naturally occurs in both desert regions. The spiny stems of ocotillo are highly distinctive, giving the appearance of tall wands or carriage whips. Perhaps the most remarkable feature of the ecology of ocotillo is how rapidly it responds to rainfall. For most of the year ocotillo stands leafless, but following a significant rain event it produces new cohort of leaves may remain on the plant for months. Under such conditions, showy red flowers are produced. With less rainfall, the leaves have a relatively short life span; they dry out and are shed within a few weeks. Ocotillo demonstrates remarkable flexibility in its ability to produce as many as five to six times in a season if rains are scattered. At the other extreme, in a dry year, leaf production may not occur. The stems of ocotillo are green and maintain a small amount of photosynthesis when the plant is leafless. The rate of photosynthesis by these stems is low, and probably serves only to balance some o the metabolic costs of respiration rather than enable new growth. "California Desert Plants, Philip W Runder, Robert J Gustafson, Michael E Kauffmann."