Counties:
Alpine
Butte
Colusa
El Dorado
Fresno
Glenn
Humboldt
Inyo
Kern
Lake
Lassen
Los Angeles
Madera
Mendocino
Mono
Modoc
Nevada
Placer
Plumas
Riverside
Santa Barbara
San Bernardino
San Diego
Sierra
Siskiyou
Tehama
Trinity
Tulare
Ventura

Jepson Bioregions:
Warner Mountains
White and Inyo Mountains
North Coast
Klamath Ranges
North Coast Ranges
Cascade Range Foothills
High Cascade Range
Sierra Nevada Foothills
High Sierra Nevada
Tehachapi Mtns
Transverse Ranges
Peninsular Ranges
Modoc Plateau
Sierra Nevada East
Mojave Desert