Mark A. Dimmitt

Behind the formidable appearance of agaves and the plants formerly grouped with them is a wealth of uses. They have long been and still are used extensively by indigenous peoples throughout North and Central America for food, fiber, and medicine. The roasted, sugar-rich agave hearts have been an important food for numerous Native American groups. Juice from the mature plants is consumed both fresh and fermented. Fermented liquid from the cooked heads is distilled into mescal. Tequila, the best-known variety of mescal, is distilled from one species, Agave tequilana. The tequila agave (mezcal azul) is a significant economic crop in southern Mexico; North Americans alone consume more than a million gallons of tequila a year.

Fiber from the leaves of Agave sisalana is the source of sisal rope, and A. fourcroydes yields henequen fiber. Sisal is a major economic product widely cultivated in Africa, Asia, as well as in the New World; it provides 70 percent of the world's hard, long fiber for ropes, rugs, and bags in recent decades. Numerous native American peoples weave baskets from the fibers of yuccas and nolinas.

The complex chemicals in this family have many uses. Compresses for wounds have been made from macerated agave pulp, and juices from leaves and roots were used in tonics. But beware-sap from many agaves can cause severe dermatitis. The juice of the more virulent agaves has been used as fish poison and arrow poison. Agaves and yuccas are used in Mexico to make soap. Yuccas were once used to provide the foam of root beer and are still used in livestock deodorant. More recently steroid drugs have been synthesized from extracts of several species in the family.

Today these plants are appreciated for their beauty and are widely used to add accents to landscape designs and mark property boundaries all over the world. Howard S. Gentry's book Agaves of Continental North America was so popular that it was reprinted in 1992, an unusual event for a botanical monograph.

As originally described by Gentry, Agavaceae consists of 18 genera and a little over 400 species, many of them native to western North America. This family is difficult to define; it has been revised by taxonomists several times in recent years.

Agaves, yuccas, and relatives were once included in the very large lily family Liliaceae. Gentry segregated agaves, yuccas, and other genera into their own family Agavaceae in the 1970s. More recently other botanists have split the old Liliaceae into many more families and removed some genera from Agavaceae, among them Nolina, Dasylirion, Sansevieria, and Dracaena. Whatever their taxonomic status, these are highly useful plants with dramatic forms.