Tufted to clump-forming from a thick woody rhizome. Leaves 10-50cm tall, the blades bi to tripinnate, composed of many small, ternate, grey-green pinnules. P.m. var. californica has fewer but denser pinnules. P. mucronata is native to California and Baja California, on dry rocky slopes below 1820m. Var. californicus is in California only, mainly above 1820m, often in coniferous forest and should be hardier.