Main sources: Main sources: Shreve, Forrest, 1951, Vegetation of the Sonoran Desert, Washington, D.C.: Carnegie Institute of Washington Publication 591; Dimmitt, Mark, "Fouquieriaceae", in Phillips, Steven & Patricia Comus, eds., 2000, A Natural History of the Sonoran Desert, Tucson: Arizona-sonora Desert Museum Press, pp. 240-43;

Ocotillo draws its name from the Nahuatl term Ocote, meaning "torch" (see below for an image of its flower!). It has wide distribution in the Sonoran Desert (from Sonora into our area, to the Colorado River north of Needles, CA, and from the El Centro CA area into the Baja peninsula), and is also considered a characteristic plant of the Chihuahuan Desert. In our area it is usually most abundant on shallow soil of coarse rocky slopes, where its roots get good aeration and receive quick wetting in summer rainstorms -- its root system being similar to the cacti (shallow and wide-spreading). It is part of the same family as the renown "Boojum" tree (which is native only to the central Baja peninsula), a family characterized by spiny stems with bundles of seasonal leaves at each spine.

Click on image below to enlarge:

Click on image below to enlarge:

Click on the image below to enlarge:

Below, a stem of new growth seen in January, 2005, near the Cow Camp. This is a substantial amount for the past year. Click on the image below to enlarge

Forrest Shreve describes the Ocotillo as resembling "a loosely held group of wands" (p. 146, and see the banner photo above). Its branches arise from a short crown and grow to a length of 9 to 12 feet, usually without forking, and mostly straight and standing at angles more than 45 degrees to the surface of the ground. In dry seasons they look like dead, gray, spiny sticks, but after moderately heavy rains (either in summer or winter) they erupt with smooth, dark green leaves, which show little evidence of succulence (see left) and which will soon dry, turn yellow, and fall if no further rains follow. (While in leaf, the plant's water requirement is very high; when not, very low.) Intermittent rains may produce as many as six or seven leaf crops in one year.

Stem growth occurs only during summer rains, with a dark red shoot forming at the tip of the growing branch with leaves linked to a small spine. Only a few stems of any single plant lengthen in a given season. In the image at left, somewhat reddish new growth has occurred during the previous summer, in the rather unusual form of a branching off an old stem (at photo center). Less recent growth stems are more grayish.


Flowers, on the other hand, appear at the end of an adequate winter rainy season, at the tips of branches, and are brilliant red. The seeds form in great numbers and are borne by the wind on their light, thin wings. They germinate readily, and many thousands of seedlings may be found in late July, but from these only two or three will survive until the following summer.

Below: a stand of Ocotillo on a south-facing slope east of the Cow Camp, August 2001:

The numbers of Ocotillo on our uplands show up clearly about a month after good rains, when their leaves begin to yellow and fall while those of surrounding plants change less quickly. At such times, the numbers turn out to be much larger than seems evident in other times:

Click on the image below to enlarge:

A noteworthy aspect of Ocotillo is that the intensity of its leafing is directly related to intensity of rainfall. For example, the following images below show the same plants illustrated above (including the banner photo at the top of the page), but these had leafed out after the unusually intense rains that hit this particular part of our uplands in early August 2006. (Click on each image to enlarge it.)


The image above left shows a much thicker appearing tree than those previously illustrated. The reason for this appears above right, where the leaflets at each node are much more numerous the ones shown above left (from August of 2002).

The O'odham would collect the Ocotillo blooms and let the nectar flow out, then eat the flower.

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