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Scientific: Pachycereus schottii (Synonyms: Cereus palmeri, Cereus schottii, Lophocereus australis, Lophocereus schottii, Pachycereus australis, Pilocereus schottii)
Common: senita, whisker cactus. The mutant form Monstrosus is known as totem pole cactus.
Family: Cactaceae
Origin: Southwest USA (Arizona), northwestern Mexico (Baja California, Sonora)

Pronounciation: Pa-key-SEER-e-us SCHOT-tee-i

Hardiness zones:
Sunset 12-13, 16-17, 21-24
USDA 9-11

Landscape Use: Strong focal point for xeric landscape themes, container plant, rock garden, large patios.

Form & Character: Upright, tree-like, branched and contorted, convoluted, dominant, towering, clumsy, bearded when mature.

Growth Habit: Evergreen, succulent perennial, slowly upright and branched to 20-feet tall with less than equal spread.

Foliage/Texture: Columnar stems are 4 to 8 inches in diameter having 5 to 10 ribs. Lower stem areoles are white and woolly with 1 to 15 very short white spines (0.1- to 0.3-inch long). The upper areoles can have numerous (>20) spines that are up to 4-inches long (like whiskers). The variety monstrosus has columnar stems dull green to light green that are smooth and irregular w/out spines; coarse texture.

Flowers & Fruits: Flowers are born on the upper stem segments, light pink to 2-inches wide. Flowers open at night only and remain open until mid-morning.  The edible fruit is red, with a red pulp. Variety monstrosus rarely flowers and fruits.

Seasonal Color: Flowers mostly from April to September.

Temperature: Species is tolerant to 15oF, variety montrosus is tolerant to 24oF.

Light: Full sun, no shade.

Soil: Well drained, mineral soils are best.

Watering: Water only occasionally if at all.

Pruning: None, except to control width by occasionally thinning out awkward or crossing branches.

Propagation: From softwood stem cuttings allow cut surface to callous over before planting directly into soil.

Disease and Pests: Susceptible to root rot in damp poorly drained soils.

Additional comments: With age, this arborescent cactus become very large occupying significant physical and visual space in the landscape. The mutant form Monstrosus is the most commonly seen mutant form of all the columnar cacti in Phoenix desert landscapes. It makes a great plant for patio containers, raised planter beds, larger xeric landscape spaces, or as a living abstract desert version of Santa's Christmas elves.

Taxonomic notes: Pachycereus is a genus of columnar cacti consisting of 10 species from the New World. This taxon was first described by (Engelm.) D.R. Hunt in Bradleya 5:93 (1987). Otherwise, there are up to nine synonyms including the genus Lephocereus, first described in the Cactus Succulent Journal (Los Angeles) 35:187 (1963).