Plants: Pencil Cholla
Walking on the paths through the Valley of Fire, we came upon a long-thorned plant that seemed to be a cactus with no planned structure. It was a series of sticks that were as fierce as a Crown of Thorns, but without anything that seemed worthy of protection. At least cholla have a fleshy arm that seems to attract birds and insects. This plant was a fortress with total protection and no castle. I believe it is known as the Pencil Cholla or (Cylindropuntia leptocaulis).
As its common with naming conventions, some cholla are known as Arizona pencil cholla. At the name suggests, Cylindropuntia arbuscula is found only in Arizona, in the south central part of the state from the Phoenix area south to the border with Mexico. However, the species we spotted in our Flocks and Rocks Trek was in southern New Mexico and appeared to be a true cactus. As suggested Cylindropuntia arbuscula is a different species from the Cylindropuntia leptocaulis.
Description of this cactus
Cylindropuntia leptocaulis is a sparingly to densely branched cactus with slender branches that bear many short, commonly spineless branchlets arranged mostly at right angles. It can grow up to 6 feet (1.8 m) tall, usually as an erect shrub or sometimes as a small tree with a trunk measuring up to 4 inches (10 cm) in diameter. The stem segments are gray-green or purplish, cylindrical, with linear tubercles that look like elongated wrinkles when dried. They can reach up to 3.2 inches (8 cm) in length and 0.25 inches (0.6 cm) in diameter. The spines are absent or mostly in apical areoles of the main branches, usually one, but occasionally up to 3 per areole. They are straight or arching, red-brown with grey-white coating and yellow at the tip, and can grow up to 1.8 inches (4.5 cm) long. There are also a few small yellow or reddish-brown glochids. The woolly areoles are white to yellow, becoming gray with age.
The flowers are funnel-shaped, pale yellow to greenish-yellow, sometimes tipped red, and can reach up to 1 inch (2.5 cm) in length (including ovary) and 0.8 inches (2 cm) in diameter. The fruits are fleshy, smooth or covered in minute glochids, red, occasionally yellow, and contain pale-yellow seeds. They are obovate and can grow up to 1.2 inches (3 cm) long and 0.5 inches (1.2 cm) in diameter.
The species we saw were dwarfed and much lower to the ground.
The specific epithet “leptocaulis” (pronounced “lep-toh-KAW-liss”) means “thin-stemmed, slender-stemmed” and refers to the slender branches of this cactus species.
Origin of this species
Cylindropuntia leptocaulis is native to the United States (Arizona, New Mexico, Oklahoma, and Texas) and Mexico (Sonora, Chihuahua, Coahuila, Nuevo León, Durango, Tamaulipas, and Zacatecas). It grows on sandy, loamy, or gravelly soils in deserts, grasslands, chaparral, woodlands, flats, bajadas, and slopes at elevations between 130 and 4,920 feet (40 and 1,500 m).
According to Wikipedia, Cylindropuntia leptocaulis are commonly known as either Tasajillo or Christmas Cholla. This fierce plant is a slender, much-branched cactus native to the southwestern United States and northern Mexico. Unlike many larger members of the genus, this species produces exceptionally thin cylindrical stems only 0.1-0.3 inches in diameter, giving the plant a delicate, twig-like appearance. The stems are divided into short segments armed with small clusters of fine spines and tiny deciduous leaves that appear briefly during active growth.
Small greenish-yellow to bronze flowers appear in spring, followed by bright red, fleshy fruits that often persist through winter. These colorful fruits provide ornamental interest long after flowering and are the origin of the common name “Christmas Cholla.” A remarkable feature of this species is that the fruits retain active areoles – the specialized buds from which cacti produce spines, flowers, and new shoots. As a result, the fruits themselves may sprout up to four new vegetative branches directly from their upper areoles, allowing the plant to spread vegetatively as well as by seed. Birds readily feed on the fruits, helping to disperse the seeds. Cylindropuntia leptocaulis thrives in full sun and sharply drained soil and is highly tolerant of heat, drought, and poor rocky soils. Suitable for USDA Zones 7-11, it is among the most cold-hardy species of Cylindropuntia and requires very little supplemental watering once established. Its fine-textured branching, persistent fruits, and unusual fruit-borne shoots make it an attractive choice for xeriscapes, desert gardens, and naturalistic plantings.
Henry E. Hooper 