Cisco Woodyaster
Xylorhiza venusta
Synonym: Machaeranthera venusta
Family: Asteraceae (A Utah Flora – Compositae) – Sunflower Family
Slightly woody perennial herbs from a woody taproot; stems 4” to 1.3' (10 to 40 cm) tall
Leaves: alternate; simple; can have hairs; entire; leaves 1” to 3.6” (2.4 to 9 cm) long, 0.08” to 0.68” (2 to 17 mm) wide
Flowers: ray flowers and disk flowers; flower head appears to be a single flower, but is composed of several flowers (a composite). Involucres 0.4” to 0.72” (10 to 18 mm) high; 12 to 36 white to pinkish to bluish or purplish rays, pistillate, fertile, 0.48” to 1.08” (12 to 27 mm) long; 60 to 120+ yellow disk flowers; disk 0.8” 1.4” (20 to 35 mm) wide
Pollinators: other genera in this family are pollinated by insects
Fruits: hairy achene – 1 seeded with hard shell
Blooms in Arches National Park: April, May, June
Habitat in Arches National Park: desert shrub communities; mainly on saline, seleniferous Mancos Shale and Morrison formations
Location seen: Delicate Arch Viewpoint trail, Delicate Arch road
Other: The genus name, “Xylorhiza”, means “woody root”. The genus name, “Machaeranthera”, means “sickle anther” which refers to the shape of the anthers. The species name, “venusta”, means “beautiful, charming”.
The type specimen was collected near Cisco, Utah, giving this plant its common name. This plant is a Colorado Plateau endemic and occurs in Carbon, Daggett, Duchesne, Emery, Garfield, Grand, San Juan, Uinta and Wayne Counties in Utah and areas in western Colorado.
This family is the most advanced and complex of the dicots. The family is rich in oils and resins and is found in every part of the world, but is infrequent in the tropical rainforest. Aquatic or semi-aquatic species are also uncommon.
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