We do have cacti in Colorado and they even grow in the mountains. The most obvious and plentiful cactus in Colorado is the Prickly Pear (Opuntia polyacantha). If you spend any time walking around the drier areas of the state up to 8000-9000 feet elevation, you may have the unfortunate experience of running into one. The spines of Prickly Pear are vicious (polyacantha means "many spines"), but its flowers are magnificent, either in yellow or magenta.
These photos were taken on the Pawnee National Grasslands, following a wet spring when blossoms were plentiful. Prickly Pear spreads easily from stem segments that are broken off and scattered, usually by animals. While Prickly Pear can tolerate cold temperatures, it rots when it absorbs too much water. The red fruit of Prickly Pear cactus is often cooked and made into jelly or syrup. In fact, every part of Opuntia is edible (once you get rid of the spines) and has long been used as a food source by native people in Southwestern United States and Mexico. There are many species of Opuntia. One of my favorites is native to the Sonoran desert and has stems that are purple in color with yellow blossoms. This Santa Rita Prickly Pear is a favorite for landscaping in desert areas.
Another cactus that grows in Colorado is the Hedgehog cactus (genus Echinocereus). It is less common, but I have found it on rocky hillsides north of Fort Collins. The name Hedgehog is derived from the Greek word echino which means (guess what?) hedgehog. This is one of those cases where the scientific classification is evolving or, at least, confusing for I have seen hedgehog cactus listed under three different genuses (Pediocactus, Echinocactus, and Echinocereus) I'm not capable of sorting it out, but hedgehog seems quite appropriate for this spiny little rascal. The thorns are often so thick that the cactus looks white on top. It does have lovely flowers, too, but I haven't been lucky enough to see them yet. Maybe this year....
