Istle (also spelt ixtle) or tampico fiber is the general name for a hard plant fiber obtained from a number of Mexican plants, chiefly species of Agave and Yucca. Istle or ixtle is also used as the common name (or part of the common name) of the plants producing the fiber. Ixtle is also the common name of a species of bromeliad, Aechmea magdalenae, grown in southern Mexico for its silky fibers.
- Jaumave istle, produced from Agave funkiana (syn. A. lophantha), is said to be the best grade. The name comes from the Jaumave Valley in the Mexican state of Tamaulipas, where it is grown. The fiber is obtained from the young inner leaves that form the central bud. Jaumave istle fibre is usually 20–40 in (51–102 cm) long, almost white, and almost as strong and flexible as sisal, produced from Agave sisaliana.
- Tula istle is produced from Agave lechuguilla or Agave univittata. The name is derived from the town of Tula, also in the Mexican state of Tamaulipas. The fiber is also obtained from the inner leaves, and is 13–30 in (33–76 cm) long and almost white.
- Palma istle is produced from the young leaves of species of Yucca, known as palmas in Spanish. The main species used is Yucca carnerosana (syn. Samuela carnerosana), although Yucca treculeana is also used. The fiber is more difficult to extract from yuccas than from agaves, requiring the leaves to be steamed first for two to four hours. Individual fibers are 20–40 in (51–102 cm) long, yellow, and usually coarser and stiffer than sisal. The fiber is described as "somewhat gummy".
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- "Taxon: Agave lechuguilla Torr.", Germplasm Resources Information Network, United States Department of Agriculture, 2009, retrieved 2013-10-22