[Wikipedia] Taxonomy: The species is named for German botanist Karl Andreas Geyer (1809-1853), who initially discovered the species near Spokane. (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: 04/02/2025).