Family: Rosaceae – Rose Family
Shrubs; 11.8” to 3.9' (3 to 12 decimeters) or more tall
Leaves: opposite; simple; entire with a small point at the tip; hairy; 0.12” to 0.48” (3 to 12 mm) long; 0.03” to 0.06” (0.8 to 1.5 mm) wide; leaves are drought-deciduous, meaning the plant can drop leaves if conditions are too dry and grow them back when conditions are more favorable
Flowers: usually no petals, or rarely 4; 4 showy sepals (yellow on top, reddish-brown on bottom); bisexual; 20-40 stamens, 1 pistil; radially symmetrical; cup-like base to flower; sepals 0.18” to 0.32” (4.5 to 8 mm) long
Fruits: Achenes – one sided fruit; seed inside has a small feathery projection. The fruit provides food for wildlife. Some plants in this family are important wildlife browse, but some have a tendency to accumulate cyanide.
Pollinators: other genera in this family are pollinated by insects
Blooms in Arches National Park: April, May
Habitat in Arches National Park: desert shrub communities in shallow sandy to clay soils
Location seen: Visitor Center area, Park Avenue, Windows, Fiery Furnace parking lot, Broken Arch, Devils Garden, Courthouse Wash Rock Art panel
Other: The genus name, “Coleogyne”, is from the Greek “koleos” which means “sheath” and "gune" which means “ovary”. The species name, “ramosissima”, means “many branched” and refers to the intricate branching habit of this shrub. The branches of this plant darken when wet, hence the common name.
This plant grows in shallow soils – less than 3 feet. Some plants could possibly be thousands of years old. From historic Arches National Park photographs it has been determined that only 1% has died in the past 100 years. A plant may be more than one individual.
The majority of this species lives in Utah, but it also lives in parts of California, Nevada, Arizona, and Colorado.
This species depends on rodents to plant seeds. Look for the burrows underneath the blackbrush.
The family is large and complex and some botanists think it should be divided into more than 1 family. The family is held together by the presence of the hypanthium (a cup-shaped structure on which the calyx, corolla, and often the stamens are inserted).
Last updated: January 21, 2022