Caudices subligneous, bases spreading and branched. Stems 1, tomentose or glabrate. Leaf blades: margins finely dissected, lateral lobes also dissected, midribs not or weakly winged. Flowering mid Apr-mid Jun. On serpentine-derived soils, rocky slopes; of conservation concern; 100-1500 m; Calif. Variety lewisrosei is found only near the Feather River and its tributaries in Butte and Plumas counties. The finely dissected leaf lobing is similar to that of the eastern species Packeramillefolia.