Loosely branching and hairy with long hairs; 1—3 feet high. Leaves oblong, thin, 2—6 inches long. Involucres narrow-campanulate, ⅓ to nearly ½ an inch high; flowers white, ¼ of an inch across or more; several in a compound cyme. On sandy banks and open mountain sides, frequent throughout the region at the lower elevations; flowering during June and July. CARDUACEÆ _Thistle Family_ Herbs with watery or resinous sap and alternate, opposite or basal leaves; flowers perfect, pistillate or neutral; borne on a common receptacle forming heads, surrounded by an involucre of few to many bracts in one or more series; calyx tube attached to the top of the ovary, the limb (pappus) of bristles, awns, teeth, scales, crown-like or wanting; corolla tubular, usually 5-lobed or -cleft, the marginal flowers frequently expanded into a ligule (ray); when the ray flowers are absent the head is said to be discoid, when present, radiate; the tubular flowers form the disc. The largest of all the families of flowering plants comprising about 760 genera and not less than 10,000 species, represented in the region by the following: Anthers not tailed at the base; heads rayed or rayless. Style branches of the perfect flowers flattened, with terminal appendages. Rays yellow or sometimes wanting. Pappus double, the outer very short. =Chrysopsis.= Pappus simple; panicle compact. =Solidago.= Rays white, purple, or blue, rarely wanting. Involucral bracts in 1—2 series, narrow; rays usually narrow and numerous. =Erigeron.= Involucral bracts in 2—5 series; rays broader and less numerous. Scales of the involucre dry, papery and appressed. =Eucephalus.= Scales of the involucre more or less herbaceous, and spreading. =Aster.= Style branches of the perfect flowers straight edged or with hairy tips. Involucre not scarious. Pappus never capillary; receptacle chaffy or bristly. Receptacle conic, chaffy; pappus none. =Rudbeckia.= Receptacle flat, chaffy; tall herbs; pappus 2 scales. =Helianthus.= Receptacle bristly; pappus a crown of scales. =Gaillardia.= Pappus capillary. Leaves all or mostly opposite. =Arnica.= Leaves alternate. Flowers white or pinkish; leaves large. =Petasites.= Flowers yellow, leaves small. =Senecio.= Involucre scarious. Receptacle chaffy; rays short. =Achillea.= Receptacle naked; rays conspicuous.