This data set include functional traits data on vascular plants collected on serpentine (ultramafic) and non-serpentine soils within the California Floristic Province. Data were initially collected as part of a statewide sampling project and used for multiple publications. Trait data include Plant Height, Specific Leaf Area, Leaf Water Content, wood density (for woody plant only). Seed mass was compiled from the KEW seed information Database and Dispersal syndromes were compiled from the literature.