Opuntia phaeacantha "New Mexico Prickly Pear

• Scientific Name: Opuntia (derived from the town Opus in Locris, a landscape in ancient Greece)
• Family: Cactaceae
• Opuntia genus has two branches
  • Prickly Pears "Platyopuntia" (flat joints)
  • Chollas "Cylindropuntia" (rounded joints)
• Close to two dozen species throughout the United States
• Native to every state except Maine, Vermont and New Hampshire
• Lifespan not more than 20 years (most short-lived of all cacti)
• Main food producing cacti - both pads and fruit.

Introduction:

The Opuntia cactus is a jointed plant made up of segments linked together to form a chain. The glochids can have full size spines but always have little tufts of hair (peach fuzz) growing along the top of warts (areole) on the walls of the cacti. They are barbed and very difficult to remove from skin.

The genus Opuntia is usually easily identified, but classifying individual plants into varieties is very difficult, as the plants react to the environment in which they are growing. The spines of the same variety can be very different if grown in the sun as opposed to being grown in a shady and moist environment. The variations due to environmental exposure also applies to stem size and shape, flower and fruit size, etc. This may result in the plant being classified as a different variety.

Prickly Pear (Platyopuntia) segments are made up of a series of discs or plates with one growing out of another. Platyopuntia are all cylindrical as seedlings and can be mistaken for Cylindropuntia. Some of the varieties can be as big as a beaver's tail or as small as a human ear. They may grow in mat forming chains along the ground or several feet tall. A few varieties are spineless with a tough leathery hide. Their moist fruits are edible, the dry fruits are not edible.

Opuntia phaeacantha

The flowers are mostly yellow but some range from rose to red and purple, lasting only a day in the hot sun. If brought indoors, flowers can last up to 3 days.
	Opuntia phaeacantha

Culture:

This plant desires sandy or gravelly well drained soil in full sun. Water can be added during growing season but should be suspended in fall and winter.

Propagation:

Because of their short life they compensate by rapid reproduction, both vegetatively and by seeds. Under natural conditions the Prickly Pear propagates itself by seed or when a segment breaks off, takes root and develops a new plant.

Problems:

Mealy bugs, which are usually introduced by another infested plant, are first noticed by their nests that appear like little blobs of cotton wool. When the bugs are crushed they product a bright red dye (cochineal). In 1788, the Prickly Pear was first introduced in Australia to establish a cochineal dye industry. Australia had such favorable conditions the plant soon became a noxious weed.

Opuntia engelmannii: Common name 'Engelmann Prickly Pear'

Opuntia engelmannii, the most common Prickly Pear, is named for Dr. George Engelmann, the botanist who first described most of the Southwest's cacti. This cactus is found in Nevada, Utah, California, Arizona, New Mexico and Texas as well as in the Mojave, Sonoran and Chihuahuan deserts. There are many forms depending on location. They can grow to 5 feet in height and have circular to oblong pads up to 10 inches long and 1/2 inch thick. Their color can range from green to blue green. Areoles are widely spaced with yellow or brownish glochids. The 4" flowers are usually yellow to orange but is also found in forms of red and blooms from late April to June. The red to purple, pear-shaped fruit, borne along the edge of the pads, is very attractive, edible, nutritious and juicy. This plant grows in sandy or gravelly soils of the plains, valleys, hillsides and ridges in desert grasslands, the deserts and pinyon-juniper and oak woodlands.

Opuntia polyacantha: Common name 'Plains Prickly Pear' *

With pads up to 5 inches, this mat or clump forming cacti can be several feet wide and 3 to 6 inches tall. The 3 inch flowers are yellow or rose to deep red, with fruit that is dry and tan. This cactus is found in sandy or gravelly soils of hillsides, flats, canyon rims, deserts, grasslands and pine or pinyon-juniper woodlands in Canada, Washington, Oregon, Idaho, Utah, Colorado, California, Arizona, New Mexico, Oklahoma, Texas and the Dakotas.

Opuntia phaeacantha: Common name 'New Mexico Prickly Pear' *

This sprawling or erect prickly pear is up to 3 feet tall and several feet wide and found both in the deserts of Texas and the cool, moist forests of the Rocky Mountains. There are more than 10 varieties of this decorative cacti. The 2 to 3 inch flowers range in color from yellow to orange with bright red centers. Transitional to pink flowers has been found near Montrose in western Colorado. These flowers bloom from May through mid-June and are a favorite food of gophers. The local variety has maroon colored fleshy fruit.

Opuntia basilaris: Common name 'Beavertail Cactus'

The stems are blue-green, often going deep purple in winter and resemble a beaver's tail. This low-growing cactus can be up to 1 foot tall and 6 feet wide. The joints can be from 2 to 8 inches long and 1 to 6 inches wide. All but the treleasei variety is spineless but the glochids have numerous microscopic barbed spines that release at the slightest touch to embed in the skin. Its range includes Nevada, Utah, California, Arizona, and the Great Basin, Mojave and Sonoran deserts. It likes sandy or gravelly soils of canyons, hillsides, flats of grasslands, oak woodlands, chaparral, pinyon-juniper woodlands and sagebrush deserts. The 2 to 3 inch flowers range from rose to magenta and bloom from late February to early June. The fruits are dry.

Opuntia fragilis: Common name 'Brittle Cactus' *

This low-growing, mat-forming cactus has joint lengths from 3/4 to 1 3/4 inches and is 1/2 to 1 inch wide. The plant can be up to several feet wide. It is the most northern growing cactus in North America and one of only three that cross the Canadian border.

The natural range of this cactus is from western and central Canada, to Washington, Oregon, Idaho, Montana, the Dakotas, Wyoming, western Nebraska, northern California, Nevada, Utah, Colorado, Kansas, Arizona, New Mexico, Oklahoma and Texas. It has small stems that detach easily and strongly barbed spines. It prefers sandy or gravelly soils of plains, hillsides and valleys of sagebrush deserts, montane forests, pinyon-juniper woodlands and grasslands. The flowers are yellow to yellow-green and bloom in June. The fruit is dry.

Opuntia rhodantha: Common name 'Cliff Prickly Pear' *

A low-growing, spreading cactus that has thick green-gray joints 2 to 9 inches long and 2 to 6 inches across. The brown glochids can be very few or quite numerous depending on the variety. The flowers are yellow, pink or reddish and bloom in early summer. Colorado flowers tend to be pink while in New Mexico they are mostly yellow. This cactus does not seem to mind cold but does not grow well in extreme heat. It grows in higher elevations, usually above 5,000 feet, in juniper woodlands ranging through Arizona, Utah, Colorado, New Mexico, Idaho and Nevada. They produce dry, spiny fruit.

Other Opuntia cacti in the Colorado State University Extension Demonstration Garden:

• Opuntia compressa (low prickly pear)
• Opuntia cyclodes
• Opuntia cymochilla
• Opuntia erinacea (hedgehog prickly pear) *
• Opuntia humifusa (smooth prickly pear)
• Opuntia littoralis
• Opuntia macrocentra
• Opuntia nicholii
• Opuntia rutila
• Opuntia sanguinicula
• Opuntia strigil
• Opuntia tenuispina
• Opuntia triacantha
• Opuntia violacea
• Opuntia tortispina

*Native to Mesa County, Colorado.

References:
Boissenvain, Charles H. and Davidson, Carol. 1940 Colorado Cacti. Abbey Garden Press, Pasadena, California.
Proctor, R.C. and Claire Meyer. 1954. The Flowering Cactus. McGraw-Hill Book Co., Inc., New York.
Manning, Reg. 1941. What Kinda Cactus Izzat? J.J. Augustin Publisher, New York.
Hewitt, Terry. 1998. Cacti, The New Plant Library. Lorenz Books, New York.
Heil, Kenneth D. and Spellenberg, Richard. 1993. Familiar Cacti of North America. Alfred A. Knopf, Inc., New York.
Weniger, Del. 1988. Cacti of Texas. University of Texas Press, Austin, Texas.

The Chinle Cactus and Succulent Club