• Double O Arch

    Arches

    National Park Utah

There are park alerts in effect.
hide Alerts »
  • Extreme Fire Danger

    Due to extremely dry conditions, fire restrictions are in effect in all national park units in Southeast Utah. More »

Cisco Woodyaster

Xylorhiza venusta

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.

Did You Know?

Pine Tree Arch

There are over 2,000 cataloged arches in Arches National Park. In order to be considered an arch, an opening must measure at least three feet (in any direction).