Epilobium rigidum
Encyclopedia
- "Siskiyou Mountains Willowherb" redirects here. Not to be confused with Siskiyou Willowherb (or Siskiyou Fireweed, E. siskiyouense).
Epilobium rigidum is an uncommon species
Species
In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...
of flowering plant in the evening primrose family
Onagraceae
Onagraceae, also known as the Willowherb family or Evening Primrose family, are a family of flowering plants. The family includes about 640-650 species of herbs, shrubs, and trees in 20-24 genera...
known by the common names Stiff Willowherb and Siskiyou Mountains Willowherb.
It is endemic to the Klamath Mountains
Klamath Mountains
The Klamath Mountains, which include the Siskiyou, Marble, Scott, Trinity, Trinity Alps, Salmon, and northern Yolla-Bolly Mountains, are a rugged lightly populated mountain range in northwest California and southwest Oregon in the United States...
of far northern California
California
California is a state located on the West Coast of the United States. It is by far the most populous U.S. state, and the third-largest by land area...
and southern Oregon
Oregon
Oregon is a state in the Pacific Northwest region of the United States. It is located on the Pacific coast, with Washington to the north, California to the south, Nevada on the southeast and Idaho to the east. The Columbia and Snake rivers delineate much of Oregon's northern and eastern...
, where it grows in dry, open areas in lower elevation coniferous forest habitat. It is sometimes a member of the serpentine soil
Serpentine soil
A serpentine soil is derived from ultramafic rocks, in particular serpentinite, a rock formed by the hydration and metamorphic transformation of ultramafic rock from the Earth's mantle....
s flora.
This is a perennial herb forming upright clumps or mats of tough, peeling stems around a woody caudex
Caudex
A caudex is a form of stem morphology appearing as a thickened, short, perennial stem that is either underground or near ground level . It may be swollen for the purpose of water storage, especially in xerophytes...
. It bears bright pink flowers with heart-shaped petals up to 2 centimeters long flanked by pointed reddish sepal
Sepal
A sepal is a part of the flower of angiosperms . Collectively the sepals form the calyx, which is the outermost whorl of parts that form a flower. Usually green, sepals have the typical function of protecting the petals when the flower is in bud...
s. The fruit is a hairy capsule up to 3.5 centimeters long.