Opuntia ficus-indica a fruit crop, and also for the vegetable nopales and other uses. Most culinary references to the "prickly pear" are referring to this species. The name "tuna" is also used for the fruit of this cactus, and for "Opuntia" in general; according to Alexander von Humboldt, it was a word of Taino origin taken into the Spanish language around 1500. Cacti are good crops for dry areas because they convert water into biomass efficiently. "O. ficus-indica", as the most widespread of the long-domesticated cactuses, is as economically important as maize and blue agave in Mexico. Because "Opuntia" species hybridize easily,
Opuntia ficus-indica the plants are used as fodder. In these cases, the spines need to be removed from the pads to avoid damage to the animals. Mostly, this is achieved by burning the spines off the pads. "Opuntia ficus-indica" for human and animal consumption is its water content in an arid environment, containing about 85% water as a water source for wildlife. The seeds contain 3-10% of protein and 6-13% of fatty acids, mainly linoleic acid. As the fruit contains vitamin C (containing 25–30 mg per 100g), it was once used to mitigate scurvy. "Opuntia" contains selenium. The red color of the