[Wikipedia] Range, Habitat: Penstemon anguineus is a species of penstemon known by the common name Siskiyou beardtongue. It is native to the mountains of Oregon and northern California, where it grows in coniferous forests, often in open areas left by logging operations. (link added by Mary Ann Machi)
Calflora:
Information on California plants for education, research and conservation,
with data contributed by
public and private institutions and individuals.
[web application]. 2025.The Calflora Database
[a non-profit organization].Available:
https://www.calflora.org/(Accessed: 04/09/2025).