Grizzlybear Cactus (Opuntia erinacea var. ursina)
Vegetation Around Las Vegas
 
Grizzlybear Cactus (Opuntia erinacea var. ursina)
Medium-sized pads with long spines (Arrow Canyon Wilderness Area)

General: Grizzlybear Cactus (Opuntia erinacea var. ursina) is low-growing cactus with broad, thin stem segments (pads). The pads are medium-sized for a pricklypear (to about 5-inches long by 3-inches wide).  The spines are dense, long (to 6 inches), usually gray, wavy, and flowing. The distinguishing feature of this variety of cactus is the long, flowing spines that sometimes completely obscure the pads.

Grizzlybear Cactus is a locally common (uncommon overall, but can be abundant in certain areas) component of vegetation communities on well-drained sandy, gravelly, and rocky soils along washes, canyons, and on upper bajadas and moderate slopes into the lower mountains in the Upper Sonoran (Mojave Desert Scrub and Pinyon-Juniper Woodland) life zone.

Around Las Vegas, this cactus is found at middle elevations in the mountains, making it difficult to find without a hike. A few can be found near Willow Springs at Red Rock Canyon NCA (Petroglyph Wall Trail).

Grizzlybear Cactus (Opuntia erinacea var. ursina)
Long spines obscure the pads (Arrow Canyon Wilderness Area)

Family: Cactus (Cactaceae).

Other Names: Opuntia polyacantha var. erinacea

Plant Form: Upright shrub spreading from the ground.

Height: To about 18-inches tall.

Grizzlybear Cactus (Opuntia erinacea var. ursina)
Spines long, gray, and wavy (Arrow Canyon Wilderness Area)

Trunk: None.

Stems: Divided into segments; flat and broad (pancake shaped). To about 5-inches long and 3-inches wide.

Stem Surface: Smooth.

Spines: Spines 4 to 24 per areole, in all areoles; to about 3-inches long (variable).

Grizzlybear Cactus (Opuntia erinacea var. ursina)
(Arrow Canyon Wilderness Area)

Glochids: Present.

Flowers: Blooms late spring and early summer. Inflorescence: Solitary from upper edge of pads. Flower: yellow to magenta, about 2-inches diameter; filaments white, style white, stigma green.

Fruit: Spiny.

Seeds:

Grizzlybear Cactus (Opuntia erinacea var. ursina)
That is one long spine sticking straight up (Arrow Canyon Wilderness Area).

Habitat: Dry, well-drained sandy, gravelly, and rocky soils on upper bajadas and moderate slopes in the mountains.

Distribution: Southern California to Utah and Arizona

Elevation: 3,000 to 7,000 feet.

Comments: This variety has recently been included in Opuntia polyacantha var. erinacea.


 
Note: All distances, elevations, and other facts are approximate. Names generally follow the USDA database.
Thanks for coming to visit!
© Jim Boone; Last updated 080116

Cactus Vegetation  Glossary Copyright, Conditions, Disclaimer Jim Boone's Home Page