About Myrtillocactus schenckii (J.A.Purpus) Britton & Rose
Myrtillocactus schenckii (J.A.Purpus) Britton & Rose is an arborescent, erect cactus that grows 2 to 7 meters (6 feet 7 inches to 23 feet 0 inches) tall. It has a short main stem, and branches form a "chandelier" shape, with much branching near the base of the trunk. Individual stems are 6 to 12 centimeters (2.4 to 4.7 inches) in diameter, have 6 to 8 ribs, and are bluish-green; mature branches can reach up to 10 centimeters (3.9 inches) wide.
Radial spines are straight, rigid, pointed at the tip, and colored black and greyish. They measure 0.5 to 1.2 centimeters (0.20 to 0.47 inches) long and 0.5 to 0.8 millimeters (0.020 to 0.031 inches) wide. There is usually 1 central spine, which is sometimes absent; the central spine is straight, grayish or black, 1 to 5 centimeters (0.39 to 1.97 inches) long, and 0.8 to 1 millimeter (0.031 to 0.039 inches) wide.
Flowers are axillary, yellowish-green to yellowish-white, and measure up to 3.5 centimeters (1.4 inches) long by 3 centimeters (1.2 inches) wide. Fruits are red, globose or ellipsoidal, 8 to 15 millimeters (0.31 to 0.59 inches) in diameter, and sometimes bear a few weak spines. Their pulp is juicy and ranges from red to brown. Seeds are asymmetric, oval, black, and wrinkled; they measure 1.1 to 1.5 millimeters (0.043 to 0.059 inches) long by 0.8 to 1.2 millimeters (0.0315 to 0.047 inches) wide.
This species has a restricted native distribution across the Mexican states of Chiapas, Oaxaca, and Puebla, and has also been recorded outside Mexico in Guatemala. It is characteristic of xeric scrublands and transition areas adjacent to low deciduous forest, growing in arid and semi-arid regions. It is typically found on gypsum and limestone soils that often have high salt content, such as those in the Tehuacán-Cuicatlán valley. It occurs at elevations between 1,300 and 2,000 meters (4,300 and 6,600 feet). Its habitat has a dry, arid, semi-warm climate with a distinct wet season in summer; average annual rainfall ranges from 380 to 450 millimeters (15 to 18 inches), and the average annual temperature is 21.2 °C (70.2 °F).
