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Arches National Park
Whipple's Fishhook (Whipple's Cholla; Fishhook Cactus)
Sclerocactus whipplei

Sclerocactus whipplei var. roseus

Some sources identify this species as Sclerocactus parviflorus.


Family: Cactaceae – Cactus Family

Perennial herbaceous or woody succulents; 2” to 1.2' (5 to 35 cm) tall or more

Leaves: spines are modified leaves; has fleshy pads; spines can be hooked; 8 to 15 ribs

Flowers: showy; usually light purple or pinkish; petaloid sepals; stamens numerous; 1 style; generally bisexual; 1.2” to 2” (3 to 5 cm) long

Pollinators: other genera in this family are pollinated by insects

Fruits: large dry or fleshy many-seeded berry

Blooms in Arches National Park: April, May, June

Habitat in Arches National Park: desert shrub and pinyon-juniper communities

Location seen: upper Courthouse wash, park road mile 4 to 8 (Great Wall)

Other: The genus name, “Sclerocactus”, is from the Greek “scleros” which means “hard” and “kaktos” which means “thistle” referring to the hard, sharp spines. The species name, “whipplei”, honors Amiel Wicks Whipple (1818-1863), an engineer for surveys of the United States/Mexico boundary in 1853-1856. The variety name, “roseus”, means “rosy”.

The root systems are shallow unless deep water. The stomates (pores) are open during the night, allowing entry of carbon dioxide, which is chemically stored; during the day the carbon dioxide is used in photosynthesis.

Pinyon Pine  

Did You Know?
Pinyon pines do not produce pine nuts every year. These delicious nuts can only be harvested every three to seven years. This irregular schedule prevents animals from adapting to an abundance of pine nuts and guarantees that at least some nuts will become new pine trees instead of a quick meal.

Last Updated: May 24, 2008 at 23:52 EST