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Arches National ParkSego Lily
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Arches National Park
Rydberg's Twinpod (Pointleaf Twinpod)
Physaria acutifolia

Physaria acutifolia

Family: Brassicaceae (A Utah Flora - Cruciferae) – Mustard Family

Perennial herbs; stems 1.2” to 9.8” (0.3 to 2.5 dm) long

Leaves: basal and alternate; simple; blue-green rounded spatula-shaped leaves; leaves reduced upwards; entire to toothed; basal leaves 0.68" to 3.8” (1.7 to 9.5 cm) long, 0.24" to 1.8” (0.6 to 4.5 cm) wide

Flowers: 4 yellow petals in the shape of a cross or crucifer; 4 sepals; 6 stamens; 1 pistil; flowers 0.3" to 0.5” (7.5 to 12.5 mm) long; nectar glands commonly 4

Pollinators: other genera in this family are pollinated by insects (specifically butterflies, moths, bees and flies); some self-fertile

Fruits: bladdery-inflated silique - a pod with 2 compartments with a thin partition

Blooms in Arches National Park: February, March, April

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

Location seen: park road mile 0 to 2.5, Park Avenue, Windows, upper Delicate Arch Viewpoint

Other: The genus name, “Physaria”, is from the Greek physa meaning “bladder” which refers to the inflated seedpods. The species name, “acutifolia”, means "with pointed leaves".

The common name, twinpod, refers to the seed's shape.

Many plants in this family are weeds and they flower early because they are annual. Many vegetables are in this family– radish, cabbage, cauliflower. A few species of plants in this family are poisonous to livestock.

Detail of petroglyph panel  

Did You Know?
Native Americans never inhabited Arches on a year-round basis, though they certainly roamed the area searching for wild game, useful plants and rocks for tool-making. Petroglyphs near Wolfe Ranch are thought to have been created by Indians from the Ute/Paiute cultures.
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Last Updated: July 18, 2007 at 21:02 EST