F. wislizenii is the species that contains palatable liquid; other species, particularly the ones with red flowers, contain oxalic acid, which causes nausea and inability to walk. Presumably the liquid could be boiled before drinking to destroy the oxalic acid. An axe or machete is needed to penetrate the tough exterior. Be careful when chopping it; the needles that break off may shoot out and ricochet like bullets. Another method is to use a rock to remove the spines, and then scoop out the crown, and pound the pulp in place. The liquid which results can be drunk. The Army manual SURVIVAL suggests slicing the pulp and eating it raw or carrying it with you as a source of water. It says that the milky juice is an exception to the general rule that milky juices or saps are poisonous. The Indians of Mexico chopped off the tops and exposed the stems to air to obtain moisture. The water is slightly greenish but potable.

Some species of Barrel lean over, pointing south, and can be used as a compass. The spines have been used as phonograph needles, fishhooks, awls, needles, and for tattooing. The cactus was used as a cooking pot. The Indians would cut off the top, scoop out the pulp, and put hot stones and food in the cavity. The Barrel Cactus is precious and has difficulty surviving with humans. Help propagate it by planting its seeds and protecting it from harm. The pulp of all of the Ferocactus is made available to cattle in time of famine or drought. It was fed to pigs. It is cut and split for forage, or cut, doused with kerosene, and burned.

The barrel cactus below was seen on our San Andreas Fault Tour.