Alameda County Thistle
Cirsium quercetorum
Care
0–0ft tall
Resistant
Friendly
Young shoots cooked as vegetable; roots eaten
East Bay hills of Alameda and Contra Costa Counties, from 500-2000 ft elevation in grassland and oak woodland habitats.
Care Guide
Planting
Plant your Alameda County Thistle in a location that mimics its native coastal grassland and open woodland habitat. This thistle is deer resistant and naturally grows low to the ground (typically under 8 inches), though it can occasionally reach up to 3 feet tall, so give it space to spread. Plant in fall or winter when the plant is dormant to give it time to establish before the growing season.
After Planting
Water regularly during your thistle's first growing season to help it establish, then gradually reduce watering as the plant matures and becomes more drought-tolerant like its wild cousins. This is a perennial, so expect it to persist year after year once established. The biggest mistake is overwatering - Alameda County Thistle evolved in naturally dry conditions, so err on the side of dry rather than wet once the plant is past its first season.
Visit Calscape for more information about Alameda County Thistle
Wildlife Supported
Insects
Primary larval host plant for caterpillars; critical food source for larvae
Pollen collection for nest provisioning
Pollen collection during flowering period for larval provisions
Birds
Seed consumption for overwintering populations; important winter food