Rigida:  Answers to key questions in Budd's Flora and Flora of Alberta leading to this species.   stems rigid stems gray puberulent or pubescent; NOT glabrous leaves firm, thick, and rigid leaves very rough, gray pubescent; NOT glabrous leaves oblong to oval; NOT linear to lanceolate heads in dense cymose clusters, these arranged in a flat-topped or corymb-like inflorescence; heads NOT racemose, heads NOT panicled with racemose branches branches of inflorescence slanting upward; NOT arching heads pedicellate; NOT sessile involucral bracts longitudinally striate ray florets usually less than 5 mm long; NOT 5-8 mm long ray florets yellow; NOT white, NOT pale yellow

 

Solidago: Answers to key questions in Budd's Flora and Flora of Alberta leading to this genus.  fibrous-rooted, NOT tap-rooted juice watery; NOT milky leaves alternate; NOT opposite leaves simple; NOT pinnatifid, NOT divided heads small and numerous, in terminal or axillary clusters; NOT solitary at ends of branches involucral bracts in 2 or more series; NOT in one series; NOT in one series with a few very much shorter outer bracts at base involucral bracts well imbricated; NOT scarcely imbricated receptacle naked; NOT chaffy or bristly flower heads with both tubular and ray florets; NOT all tubular; NOT all ray ray (ligulate) florets either pistillate or neutral; NOT perfect ray florets yellow; NOT blue, NOT purple, NOT white to pink stamens united to form a tube around the pistil pappus simple (bristles sometimes unequal, but not distinctly divided into two lengths); NOT double (outer inconspicuous and very much shorter than the inner) pappus composed of hairs; NOT composed of scales or bristles, NOT chaffy, NOT of firm awns, NOT absent