In the vast, warm desert regions of North America, a unique plant grows in the shallow soils among the rocky slopes, washes, grasslands and mesas of both the Chihuahuan and Sonoran deserts. Ocotillo, Fouquieria splendors, with their small trunks and large cane-like unbranched spiny stems are one the the easiest of plants to identify in these vast deserts.
Designed to survive
The ocotillo is a drought resistant deciduous shrub. It produces between six to 100 cane-like branches from a shallow-rooted crown and which can grow from 9 to 30 feet (2 to 9 meters) in length. Sharp, rigid spines (some of which grow to 1.5 inches or 4 centimeters), cover the length of the each stem.
Waiting for the rain
Thick, leathery ovate leaves sprout from the base of each spine after a soaking rainfall. Leaves are commonly 3/4 to 1.5 inches (2 to 4 cm) in length, but some are known to have grown to 2 inches (5 cm) long and reach maturity within 14 days. As the landscape becomes arid again, the leaves will dry and fall. Ocotillo appear leafless most of the year, but under normal desert rainfall, will produce four to five crops of leaves annually.
The Ocotillo become semi-dormant when it is leafless. The shrub's life-sustaining moisture is further preserved by its waterproof bark, which is interspersed with ribbons of moist, green tissue beneath the brown cuticle of the bark.
These green ribbons also contain chlorophyll and carry on the process of photosynthesis during the dry seasons when the Ocotillo is leafless.
A mix of traits
Ocotillo appear to be strange, woody shrubs but often behave like a succulent. Like succulents, Ocotillo have a shallow root system. From a main taproot, a few lateral roots grow just below the soil surface. The taproot will grow to a depth of 3 to 6 inches (8 to 15 cm) below the surface of the soil.
Ocotillo's bisexual, bright red-orange flowers are clustered at the tips of each stem. They often appear after a rainfall and before the sprouting of leaves. Flowers of the ocotillo have nectar-secreting glands on the flower buds.
A variety of insects and hummingbirds frequent the flowers, aiding fertilization. Botanists think that a mature ocotillo will produce at most a few hundred viable winged seeds each year that wait to germinate until appropriate rainfall occurs.
Making it home
The ocotillo grows at elevations from sea level to 6,700 feet (2,050 meters). They seem to favor well-drained soils that are rocky, shallow and are of limestone or granite origin. When found growing on hillsides, they favor south-facing slopes.
Putting down roots
Ocotillo are often found growing near desert riparian habitats. They will grow near flowing rivers, floodplains, as well as dry desert washes. They are often found growing among Fremont cottonwood, Populus fremontii, trees as well as a basque of honey mesquite, Prosopis glandulosa.
Protecting the young
A young ocotillo is seldom found on disturbed soils. They are often found under the protective canopy of mature desert plants.
An ocotillo may naturally live between 60 to 100 years.
Making odd acceptable
Ocotillo are a part of the Family Fouquieriaceae, which only contains 11 species members, all of which are only found in this warm, arid portion of North America. "Odd-looking" would be a common descriptor for members of this family. All have spiny stems with groupings of seasonal leaves at each spine, which sprout after desert rainfall. The bizarre and rare boojum, Fouquieria columnaris, of the central Baja California pennisula (shown here) is a close cousin of the more common ocotillo.
Ocotillo have long been used by the native desert people. Stems have been used for fencing and will actually sprout when planted, resulting in a beautiful living fence.
Clusters of flowers seeped in water produce a refreshing, sweet tea and are also used in salads, adding a tangy flavor. They are a common plant found in the desert landscaping of many hot desert homes.