• Double O Arch


    National Park Utah

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Mountain Pepperplant (Mountain Pepperweed, Peppergrass)

Lepidium montanum

Lepidium montanum

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

Perennial or biennial herbs; stems 1.2” to 3.9' (0.3 to 12 dm) tall

Leaves: basal or basal and alternate; simple; entire to pinnatifid; can have hairs; 0.2” to 5” (0.5 to 12.5 cm) long, 0.12” to 1” (3 to 25 mm) wide

Flowers: 4 white petals in the shape of a cross or crucifer; 4 sepals; typically 6 stamens (with 2 outer shorter than the inner 4); 1 pistil; flowers in corymbs or racemes; usually radially symmetrical; nectar glands commonly 4; petals 0.1 to 0.14” (2.5 to 3.5 mm) long

Pollinators: other Lepidium species are pollinated by insects

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

Blooms in Arches National Park: March, April, May, June, July, August

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

Location seen: widespread, upper Courthouse wash, Windows, Fiery Furnace parking lot, Devils Garden

Other: The genus name, “Lepidium”, is from the Greek “lepis” meaning “scale” and is a reference to the flattened shape of the fruit pods. The species name, “montanum”, means “of the mountains”.

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?

Landscape Arch

Landscape Arch is the longest arch in Arches National Park, measuring 306 feet from base to base. In 1991, a massive slab of rock fell from its underside, resulting in an even thinner ribbon of rock.