Chorizanthe valida is a rare species of flowering plant in the buckwheat family known by the common name Sonoma spineflower.

This rare plant once had a wider distribution; specimens were collected many decades ago in neighboring Sonoma County.

[3] The soil, remnants of a Pleistocene dune system, can bear only drought-tolerant plants because it cannot retain much water.

[3] The overall effects of cattle on the land are not certain; they may actually be a positive force in the life of the rare plant.

[3] The plant is limited to two relatively small populations, so any one severe event such as wildfire or drought could drive it to extinction.