Ferocactus is a genus of barrel cacti from Mexico and the southwestern United States, with the species varying greatly in size, spination, and flower color. This one is the orange-flowered F. pilosus, from north-central Mexico. Its flowers do not open as widely as those of other species, but their vivid orange color is eye-catching. Plants may be single, but often they form a clump, with the stems starting out globular and becoming columnar with age. In nature, plants may be up to 3 meters tall, but I have not seen plants of that size in cultivation. The particular specimen shown has more of the wispy hair-like spines than one usually sees in the species, but the stout red spines are always present.