Monographs Details: Coreopsis
Authority: Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.
Description:Genus Description - Heads radiate, the rays few, often 8, conspicuous, usually neutral, yellow or rarely pink or white, sometimes marked with reddish-brown at base; invol bracts biseriate and dimorphic, all joined at the base, the outer narrower and usually shorter, commonly more herbaceous than the inner; receptacle flat or slightly convex, its bracts thin and flat; disk-fls perfect and fertile; style-branches flattened, with short or elongate, subtruncate to caudate, hairy appendage; achenes flattened parallel to the invol bracts, usually winged, not beaked; pappus of 2 smooth or upwardly barbed, short awns or teeth, or a minute crown, or obsolete; herbs (ours) with opposite or rarely alternate, entire to pinnatifid or ternate or dissected lvs. 100, mainly New World.