This section is from the book "A Manual Of Weeds", by Ada E. Georgia. Also available from Amazon: A Manual Of Weeds.
Native. Perennial. Propagates by seeds and by the rooting of broken joints. Time of bloom: June to August. Seed-time: July to September. Range: Ohio, Michigan, and Minnesota, southward to Kentucky,
Missouri, and Texas. Habitat: Dry soil; rocky hills and pastures.
In the arid lands of the Southwest, Prickly Pear is hardly to be considered a weed, for there it is singed of its spines and furnishes an emergency food for stock during the season of drought when other forage is unavailable. But cattle prefer grasses to cactus and in ground where the better forage can be made to grow the cactus should be suppressed. If, under stress of hunger, the plant is eaten by stock without the removal of the spines, they often penetrate or lacerate the intestines, or sometimes form interlaced prickly masses or phytobezoars which close the passage and cause death. (Fig. 202.)
This is a variable species, but is usually prostrate and spreading, its roots often tuberous, and all joints are capable of rooting at the lower margins, forming new plants. Joints usually about two to six inches long and two to four inches wide, sometimes twice as large, deep green, thick, fleshy, obovate to rounded, bearing when young a few awl-shaped leaves that soon fall away; in the axil of each leaf is a small rounded elevation, usually somewhat woolly, bearing a cluster of reddish brown bristles and a few spines or a single strong one, sometimes none. Flowers yellow, sometimes with a reddish center, nearly three inches broad, the many petals slightly united at base, the stamens very numerous, the style with two- to seven-parted stigma; ovary inferior or below the flower and one-celled. Fruit a thick club-shape, nearly two inches long, not spiny, with a fleshy purplish pulp, edible, with an insipid or slightly acid taste.
Prickly Pear may be killed by burning, as stockmen of the arid lands discovered when removing the spines for the benefit of their cattle, especially if the work is done with a gasoline torch applied to the growing plants. On land capable of supporting better growths cultivation and liberal fertilization of the ground should be the method used for suppression of the prickly pest, reseeding heavily with some of the most drought-resistant grasses and clovers.