About Ferocactus pilosus (Salm-Dyck) Werderm.
Ferocactus pilosus (Salm-Dyck) Werderm. can grow as individual single plants or form large clumps, growing up to 3 meters tall and 50 cm (20 inches) in diameter. It bears 13 to 20 non-humped ribs that have sharp edges when the plant is young, and become rounded as the plant matures. Its areoles grow very close together, appearing almost merged into one another. The spines are bright red or yellow, spreading, covered in fine hairs, and slightly curved, which makes it hard to tell the difference between central and radial spines. There are 6 to 12 mostly red, strong central spines that reach up to 5 cm (2.0 inches) in length, while the radial spines are typically reduced to many small, whitish bristles. Yellow to red flowers grow in circles around the tip of the shoot, and measure up to 4 cm (1.6 inches) long and 2.5 cm (0.98 inches) in diameter. The yellow, egg-shaped fruits are roughly 3 to 4 cm (1.2 to 1.6 inches) long. This cactus is endemic to the Chihuahuan Desert in northeastern Mexico. It is native to the Mexican states of Coahuila, Durango, Nuevo Leon, San Luis Potosí, and Tamaulipas, where it grows on rocky limestone slopes.