California Yarrow

Achillea californica Pollard, Bull. Torrey Club 26: 369. 1899
Achillea Millefolium f. californica H. M. Hall, Univ. Calif. Publ. Bot. 3: 211. 1907.
A robust peremiial, with a creeping rootstock; stem 5-10 dm. high, usually branched above, striate or sulcate, illous, especially above, with long hairs; leaves numerous, bior tri-pinnatifid, sparingly villous, the lower petioled, 10-15 cm. long, 2-3 cm. wide, the upper sessile and clasping, lanceolate in outline, 1-2 cm. wide; rachis merely margined; primary diisions ovate in outline, spreading, the ultimate ones linear or lance-linear, spiuulose-tipped; heads numerous, in compound corymbiform panicles; involucre 5—6 mm. high, 4 mm. broad, rather densely villous; bracts about 20, in 4 series, all obtuse or rounded at the apex, the outer oval, the inner oblong; margins brown; ray-flowers 5 or 6; ligules white, orbiciUar or roundedoval, 3-4 mm. long; disk-flowers 25-30; corollas 3 mm. long, yellowishwhite ; achenes 2 mm. long, thick-margined.
Type locality: Sea coast at Santa Isabel, California. Distribution: California to Washington and Idaho.