Epilobium rigidum is an uncommon species of flowering plant in the evening primrose family known by the common names stiff willowherb and Siskiyou Mountains willowherb. It is endemic to the Klamath Mountains of far northern California and southern Oregon, where it grows in dry, open areas in lower elevation coniferous forest habitat. It is sometimes a member of the serpentine soils flora.
Epilobium rigidum
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