Jumping or Chain-fruit Cholla (Opuntia fulgida)

Jumping cholla or chain fruit cholla get to be pretty big, a dozen or more feet tall, and the mature ones can grow long chains of fruit. The fruit is pear shaped and about an inch and a half long. The trunk-like base gets much darker as it ages and loses many of its spines. The fruit chain grows each year as the new flowers bud out at the end of last year's fruit.
Jumping cholla gets its name from the way it most often propogates, by letting pieces of itself break off easliy from animals or severe weather. The pieces root and grow clone plants. As a person walks past, one of the long barbed spines can snag clothing and a loose segment of the plant can pop or "jump" onto a surprised hiker. The spines are sharp and their barbed structure cause them to work their way into whatever they touch, often causing a painful extraction from the skin and continued penetration into shoes. (With similar propogation methods one can see why some folks use the name Jumping Cholla for Teddy Bear cholla, too.)
The tree-like jumping chollas create forests of cloned plants in the Sonoran Desert. They can also grow at altitudes of up to 4000 feet so animals like bighorn sheep will supplement their diet with the chain fruit to get through a drought.
We also noticed bird nests in many of taller chain-fruit chollas. Apparantly the cactus wren likes the safety of the high spiney branches.