California alder
- kingdom: Plantae
- phylum: Tracheophyta
- class: Magnoliopsida
- order: Fagales
- family: Betulaceae
- genus: Alnus
- species: Alnus rhombifolia
Davis- Glen Avon
- Guerneville
- Idyllwild
- Idyllwild-Pine Cove
- Ione
- Kentfield
- La Cañada Flintridge
- La Crescenta-Montrose
- Ladera
- Lagunitas-Forest Knolls
- Laytonville
- Los Angeles
- Mira Loma
- Mission Canyon
- Monte Rio
- Palm Springs
- Ross
- San Anselmo
- San Antonio Heights
- San Bernardino
- Santa Cruz
- Ukiah
- Walnut Grove
- Weaverville
- West Menlo Park
California- Boise
Idaho- Corvallis
- Cottage Grove
- The Dalles
- Umatilla
Oregon- Dallesport
- White Salmon
Washington
United States