jumping cholla / teddy bear cholla
Opuntia bigelovii
Family: Cactaceae.
Type: Perennial plant.
Leaves: Modified into spines. This protects the stems against animals that would eat the stems for their water. The spines also reduce water loss by shading the stem (where the stomata are), and by reducing leaf surface area.
Twig: Stems are succulent and round, and are green and photosynthetic (brown parts are old stems that are functional but non-photosynthetic). Pads can break off and resprout, allowing asexual reproduction; cactuses grow so slowly that this mode of reproduction is often more effective.
Fruit & Flower: Fruits are pictured below: short, stubby and cylindrical, with spines. If the spines are removed, prickly pear fruit are edible. Seeds are dispersed by birds and small mammals. Flowers are big and showy.
Miscellaneous: There are dozens of species in Opuntia with round pads like the jumping cholla; this species is simply a representative example. Its name come from the way its spines almost seem to jump out and get you.