Alternate name: Snowball Cactus
Family: Cactaceae, Cactus view all from this family
Description One or a few tiny, nearly spherical stems have several white, rose, or yellow flowers near top.
Habit: succulent native perennial shrub; variable.
Height: 2-8 in or more.
Stem: usually solitary, spherical to oval, spiny, with diagonal furrows in a pineapple-like pattern, 1-6 in (1-15 cm) tall, rarely to 10 in (25 cm) tall, 1-6 in (1-15 cm) diameter.
Leaf: spine, smooth, straight, hard; radial, 15-35 per areole, white or cream, 0.125-0.5 in (3-13 mm) long; central, 4-11 per areole, reddish-brown to black, lighter at base, 0.2-0.8 in (5-21 mm) long.
Flower: white, pink, magenta, yellow, or yellow green, vase-shaped, 0.5-1.5 in (12-38 mm) wide, 0.4-1 in (10-25 mm) tall; may remain closed on cloudy days.
Fruit: round to cylindrical berry, green to greenish-red to tan, drying to reddish-brown, to 0.25-0.5 in (6-12 mm) long, 0.2-0.4 in (5-10 mm) diameter.
Warning This cactus has very sharp spines.
Flower April to July.
Habitat Powdery soils among sagebrush and pinon and juniper, montane, and prairie grasslands, coniferous forests; 4600-11,500 ft (1400-3500 m); also cultivated ornamentally.
Range Eastern Washington to west-central Nevada and northern Arizona; east to northern New Mexico, western Colorado, western South Dakota, and western Montana; also reported in Kansas.
Discussion Also known as mountain ball cactus, Simpson's footcactus, hedgehog cactus. Three varieties are recognized. Protected in Arizona and Nevada. Flowers may be pink on east-facing slopes, yellow on west-facing slopes.
This cactus is fairly popular with collectors. Other species of the genus are rare. Mass collecting of cacti is inexcusable, but even the person who digs only one has a detrimental effect, for if many take only "their share" eventually entire plant populations are depleted.