Cholla of the Sonora, Part 1

Explanation: Here is a striking plant to enjoy but not touch. We are in the Sonoran Desert of northwest Mexico and southwest U.S, home of the cholla cactus.

What a striking plant this is. And I also use "striking" literally, as this plant is also known by the knickname of "jumping cholla" because its spines are barbed and the spiny clusters seem to jump off the plant, attach themselves to your clothes, and even embed into your skin.

What could be the adaptive advantage of such a structure? Think about how the plant might use passing mammals -- people, sheep, foxes, and others -- to serve as dispersal mechanisms for the plant. Aha.

An "old growth" cholla in the town of Oracle,
north of Tucson, in southern Arizona, USA.

Chollas can become problematic when they take over livestock rangelands, particularly during periods of drought when grasses die back. Various methods exist for controlling cholla, including use of fire, chemicals, and mechanical physical methods.

Next week we will explore more of the symbiotic relationships of cholla and its wildlife neighbors.

Until then, enjoy this fine desert evening in the Sonoran Desert of southern Arizona:

EPOW - Ecology Picture of the Week