Canescens: Answers to key questions in Budd's Flora and Flora of Alberta leading to this species. 

	plants of dry habitats
	plants biennial, with a taproot; NOT [plants perennial, with rootstocks or root crowns and fibrous roots]
	leaves entire or toothed; NOT [leaves pinnately dissected]
	involucral bracts glandular sticky
	ray florets present; NOT [ray florets lacking or inconspicuous]
	ray florets blue to bluish purple

Aster: Answers to key questions in Budd's Flora and Flora of Alberta leading to this genus. 

	juice watery; NOT [juice milky]
	leaves appearing before the flowers; NOT [leaves appearing after the flowers]
	plants usually with leafy stems; NOT [plants low, stemless, tufted]
	basal leaves NOT cordate or sagittate
	NOT [basal leaves mostly 1-6 cm long, linear to oblanceolate or spatulate, forming a dense rosette; plants with a well-developed taproot; and either densely caespitose, seldom more than 5 cm tall, the heads sessile among the leaves, or with stout, simple stems, 5-15 (25) cm tall, heads solitary, involucres 2-4 cm wide, bracts ciliate to pectinate or fimbriate, rays blue and achenes densely pubescent, obovate to triangular]
	leaves alternate or basal; NOT [leaves opposite]
	leaves not extending beyond flowers; NOT [leaves usually extending beyond the flowers]
	involucral bracts either subequal and the outer leafy or more commonly evidently imbricate, with chartaceous base and evident green tip, sometimes chartaceous throughout; NOT [involucral bracts subequal or more or less imbricate, often green in part, but neither definitely leafy nor with chartaceous base and herbaceous green tip] (FOA)
	bracts in several series; NOT [bracts in 1 or 2 series] (BF)
	flower heads with both tubular florets and ray florets (radiate heads)
	ligulate florets pistillate or neuter; NOT [ligulate flowers perfect]
	ray florets conspicuous
	ray florets 10-50; NOT [ray florets 50 or more] (BF)
	rays white, to pink, purple or blue; NOT [rays yellow or orange]
	stamens united to form a tube around the pistil
	styles-branches ordinarily more than 0.5 mm long; NOT [style-branches 0.5 mm long or less, or obsolete]
	style-branches lanceolate or narrower; NOT [style-branches lanceolate or broader]
	style-branches acute or acuminate; NOT [style-branches acute to obtuse]
	pappus composed of numerous hairs; NOT [pappus absent or composed of a few hairs] (BF)
	pappus of capillary bristles, at least in part; NOT [pappus of 1 or 2 short awns, a mere crown or none] (FOA)