• Double O Arch

    Arches

    National Park Utah

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.

Did You Know?

Tadpole Shrimp

Naturally occurring sandstone basins called “potholes” collect rain water and wind-blown sediment, forming tiny ecosystems where a fascinating collection of plants and animals live. Tadpole shrimp, fairy shrimp and many insects can be found in potholes. More...