Group 2

1	Plants stoloniferous; basal leaves not rosulate (subopposite).		72 Draba ogilviensis (in part)
+	Plants not stoloniferous (usually cespitose); basal leaves rosulate		(2)
2 (1)	Abaxial surface of leaf blades glabrous		(3)
+	Abaxial surface of leaf blades pubescent		(9)
3 (2)	Fruit valves pubescent, trichomes simple and 2-4-rayed; styles (0.7-)1.6-3 mm; petals 5.5-8 mm; n California and s Oregon.		46 Draba howellii (in part)
+	Fruit valves glabrous or puberulent, trichomes simple; styles 0.02-1.2(-1.8) mm; petals 1.5-5(-6) mm; not California nor Oregon		(4)
4 (3)	Racemes bracteate; basal leaf blades linear to linear-oblanceolate.		40 Draba graminea
+	Racemes ebracteate; basal leaf blades usually obovate to oblanceolate, rarely linear-lanceolate		(5)
5 (4)	Cauline leaves 1; fruits plane; styles 0.02-0.4(-0.6) mm		(6)
+	Cauline leaves (1 or) 2-8; fruits slightly twisted or plane; styles (0.4-) 0.7-1.2(-1.8) mm		(7)
6 (5)	Petals yellow (often fading white), oblanceolate, 1.5-2.5(-3) × 0.5-1 mm; stems glabrous or with simple trichomes; styles 0.02-0.1 mm.		29 Draba crassifolia (in part)
+	Petals white, obovate, 3-5 × 1.8-3 mm; stems glabrous or with 2-8-rayed trichomes; styles 0.1-0.4(-0.6) mm.		55 Draba lactea (in part)
7 (5)	Basal leaves undifferentiated into blade and petiole, 0.5-0.8 cm, persisting as a whole, imbricate, blade margins with setiform trichomes.		43 Draba heilii (in part)
+	Basal leaves differentiated into blade and petiole, 1.2-8.5 cm, petiole persisting, not imbricate, blade margins without setiform trichomes		(8)
8 (7)	Fruits lanceolate to ovate-lanceolate, (7-)8-14 × 3-5 mm; rachises pubescent (trichomes crisped); Colorado, Montana, Utah Wyoming.		28 Draba crassa
+	Fruits linear-elliptic to elliptic, 5-10(-13) × 1.5-2.5 mm; rachises usually glabrous, rarely pubescent (trichomes non-crisped); se Arizona, s New Mexico, w Texas.		107 Draba standleyi (in part)
9 (2)	Fruit valves pubescent, trichomes 2-12-rayed		(10)
+	Fruit valves glabrous, pubescent, or puberulent, trichomes simple		(13)
10 (9)	Styles 1.4-3.4 mm; cauline leaves (4-)6-10(-13); racemes (10-)18-55(-67)- flowered; petals yellow, linear.		26 Draba corrugata (in part)
+	Styles 0.1-0.8 mm; cauline leaves 1-3; racemes 2-20-flowered; petals white, spatulate to obovate		(11)
11 (10)	Fruits 2-5 × 1.5-2 mm; ovules 36-52 per ovary; petals 1.5-2 × 0.7-0.8 mm.		120 Draba yukonensis
+	Fruits 4-9.5 × 2-4 mm; ovules 20-36 per ovary; petals 3-5 × 1.5-2.5 mm		(12)
12 (11)	Fruits with 2-4-rayed and, sometimes, fewer, simple trichomes; petals 3-4 mm; stems proximally with branched trichomes 2-6-rayed.		8 Draba arctogena (in part)
+	Fruits with (2-)5-12-rayed trichomes; petals 3.5-5 mm; stems proximally with branched trichomes 4-10-rayed.		71 Draba oblongata (in part)
13 (9)	Styles (0.7-)1-3 mm; fruits usually twisted, rarely plane; petals (4-)4.5-7.5 mm		(14)
+	Styles 0.01-1(-1.2) mm; fruits not or, rarely, slightly twisted; petals 1.5-4(-4.5) mm		(17)
14 (13)	Cauline leaf blade margins dentate; fruiting pedicels horizontal to divaricate; se Arizona.		15 Draba bifurcata (in part)
+	Cauline leaf blade margins entire; fruiting pedicels usually ascending, rarely divaricate-ascending; Arizona, Colorado, New Mexico, Texas, Wyoming		(15)
15 (14)	Fruits usually twisted (to 3 turns), rarely plane; stems proximally with trichomes 0.4-2.2 mm; ovules 20-34 per ovary; c Colorado, n New Mexico, se Wyoming.		111 Draba streptocarpa
+	Fruits usually twisted (to 1 turn), rarely plane; stems proximally with trichomes 0.1-0.7 mm; ovules 12-24 per ovary; se Arizona, s New Mexico, w Texas		(16)
16 (15)	Basal leaves undifferentiated into blade and petiole, 0.5-0.8 cm, persisting as a whole, imbricate, blade margins with setiform trichomes.		43 Draba heilii (in part)
+	Basal leaves differentiated into blade and petiole, 1.2-8.5 cm, petiole persisting, not imbricate, blade margins without setiform trichomes.		107 Draba standleyi (in part)
17 (13)	Annuals, biennials, or perennials (not cespitose); fruiting pedicels (3-)5-14 (-16) mm		(18)
+	Perennials (cespitose); fruiting pedicels 1-6 mm		(19)
18 (17)	Abaxial surface of leaf blades pubescent with 2-4-rayed trichomes; stems pubescent, trichomes simple and 2-rayed.		2 Draba albertina (in part)
+	Abaxial surface of leaf blades glabrous or with some simple and 2-rayed trichomes; stems usually glabrous, rarely pubescent basally, trichomes simple.		29 Draba crassifolia (in part)
19 (17)	Petals yellow, 1-2 mm wide; styles (0.2-)0.3-1.2 mm		(20)
+	Petals white, 0.4-1(-1.5) mm wide; styles 0.05-0.2(-0.3) mm		(22)
20 (19)	Abaxial surface of leaf blades with sessile or subsessile, appressed, 2-4-rayed trichomes; fruits ovate, 4-8 mm; styles 0.2-0.3 mm.		119 Draba weberi
+	Abaxial surface of leaf blades with stalked 2- or 3-rayed trichomes; fruits lanceolate to oblong-lanceolate, 4-13 mm; styles 0.3-1.2 mm		(21)
21 (20)	Petals 2-2.5(-3) mm, erect, not clawed; anthers oblong, 0.6-0.9 mm; fruits plane; rachises usually glabrous, rarely sparsely pubescent.		36 Draba exunguiculata
+	Petals 3-4.5 mm, not erect (flared, clawed); anthers ovate, 0.3-0.5 mm; fruits twisted or plane; rachises pubescent.		42 Draba grayana
22 (19)	Fruit valves glabrous; stems glabrous or, rarely, sparsely pubescent (trichomes straight); petals 2-3.5 × 0.8-1.5 mm.		37 Draba fladnizensis (in part)
+	Fruit valves usually pubescent, rarely glabrous; stems pubescent (trichomes crisped); petals 1.5-2 × 0.4-0.8 mm		(23)
23 (22)	Racemes 2-7-flowered, rachises glabrous; sepals caducous; fruits lanceolate, flattened; Yukon.		54 Draba kluanei
+	Racemes (3-)6-13(-17)-flowered, rachises pubescent or, rarely, glabrous; sepals persistent; fruits ovoid to subellipsoid, slightly inflated basally; e California.		64 Draba monoensis (in part)