Teddy-bear Cholla

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Teddy-bear Cholla

Scientific classification
Kingdom: Plantae
Division: Magnoliophyta
Class: Magnoliopsida
Order: Caryophyllales
Family: Cactaceae
Genus: Opuntia
Subgenus: Cylindropuntia
Species: O. bigelovii
Binomial name
Opuntia bigelovii
Engelm.

The teddy-bear cholla (Opuntia bigelovii) is a cactus native to California and Arizona (USA) and northwestern Mexico. They grow in desert regions at elevations from 30 to 600 m (100 to 2000 ft). It is an attractive plant, having a soft appearance due to its solid mass of very formidable spines that completely cover the stems. From a distance, the stems appear soft and fuzzy, giving it the name "teddy bear".

The teddy-bear cholla is an erect plant, standing 0.3-2 m (1-5 ft) tall with a distinct trunk. The branches are at the top of the trunk and are nearly horizontal. Lower branches typically fall off, and the trunk darkens with age. The silvery-white spines, which are actually a form of leaf, almost completely obscure the stem with a fuzzy-looking, but impenetrable, defense. The spines are 2.5 cm (1") long and are covered with a detachable, paper-like sheath.

Exposed green flesh of cholla after stem detached
Exposed green flesh of cholla after stem detached

The yellow-green flowers of this cactus emerge at the tips of the stems in May and June, and the fruits that follow usually have no viable seed. Flowers are usually 3 cm (1-3/8") in length. The fruit is 2 cm (3/4") in diameter, tuberculate, and may or may not have spines. These cacti produce few seeds, as the plant usually reproduces from dropped stems. These stems are often carried for some distance by sticking to the hair of animals. Often small "forests" of these chollas form that are largely clones of one individual.

In the lower Colorado River valley, the most dense cholla forests are at higher elevations, in the rockiest sites. There are fewer Sonoran Desert, or Colorado Desert plants in association, but three are common, though in reduced size: the Ocotillo, the Saguaro, and a relative cholla, a finger-leaf cholla, with 7-10 in fingers, and of similar height, and similar to the teddy-bear in appearance, but a more open plant.

Like its cousin the jumping cholla, the stems of this cactus detach easily and the ground around a mature plant is often littered with scattered cholla balls and small plants starting where these balls have rooted. When a piece of this cholla sticks to an unsuspecting person, a good method to remove the cactus is with a hair comb. The spines are barbed, and hold on tightly. Desert pack rats such as the Desert Woodrat gather these balls around their burrows, creating a defense against predators.

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Teddy-bear cholla
Teddy-bear cholla
Close up of teddy-bear cholla
Close up of teddy-bear cholla