Group 10

1	Abaxial surface of leaf blades with pectinate, subdendritic, or some 7-12-rayed, stellate trichomes		(2)
+	Abaxial surface of leaf blades with 2-6-rayed trichomes		(14)
2 (1)	Styles 1.5-3(-3.8) mm; seeds winged; anthers 0.7-0.9 mm.		88 Draba pterosperma
+	Styles (0.05-)0.1-1(-1.2) mm; seeds not winged; anthers 0.2-0.7 mm		(3)
3 (2)	Abaxial surface of leaf blades with some pectinate trichomes		(4)
+	Abaxial surface of leaf blades with stellate or subdendritic trichomes		(5)
4 (3)	Fruits 5-9(-11) mm, flattened; petals 4-6 mm; sepals 2.5-3.5(-4) mm; leaf blades usually with obscure midveins.		48 Draba incerta (in part)
+	Fruits 3-6(-7) mm, inflated; petals 2.5-4 mm; sepals 1.5-3 mm; leaf blades with prominent midveins.		73 Draba oligosperma (in part)
5 (3)	Fruit valves pubescent, trichomes 2-6-rayed		(6)
+	Fruit valves glabrous or pubescent to puberulent, trichomes primarily simple and 2-rayed		(9)
6 (5)	Plants not pulvinate; leaf blades 0.4-2.3(-3) cm × 1-6.5 mm; petals white; ovules 20-42 per ovary		(7)
+	Plants pulvinate; leaf blades 0.2-0.8 cm × 0.5-1.5(-2) mm; petals yellow; ovules 4-12(-16) per ovary		(8)
7 (6)	Basal leaf blades apically with simple trichomes, midveins distinct abaxially; seeds 0.8-1.1 × (0.6-)0.7-0.8 mm.		7 Draba arctica (in part)
+	Basal leaf blades apically without simple trichomes, midveins obscure abaxially; seeds 0.6-0.8 × 0.4-0.6 mm.		25 Draba cinerea (in part)
8 (6)	Fruits inflated basally (symmetric), plane, (2.5-)3-4(-5) mm; Alberta, British Columbia, California, Montana, Utah, Wyoming.		70 Draba novolympica (in part)
+	Fruits flattened (asymmetric), twisted or plane, 4-8(-10) mm; ec California.		100 Draba sierrae (in part)
9 (5)	Seeds 1.5-2.2 × 1-1.4 mm; fruits 3-5 mm wide; styles 0.5-1.2 mm; petals yellow; ovules 8-16 per ovary		(10)
+	Seeds 0.7-1.3 × 0.5-0.8 mm; fruits 1-2.5(-3) mm wide (-5 mm wide in D. oxycarpa); styles 0.05-0.6(-1 in D. scotteri) mm; petals white or creamy white (yellow in D. scotteri and, sometimes, D. oxycarpa); ovules (10-) 12-28 per ovary		(11)
10 (9)	Leaf blades each with prominent midvein; basal blades linear to linear-oblanceolate, 0.8-1.5 mm wide; petals pale yellow; fruits slightly inflated basally; w Montana, nw Wyoming.		79 Draba paysonii (in part)
+	Leaf blades each with obscure midvein; basal blades oblanceolate to obovate or suborbicular, 2-4.5 mm wide; petals bright yellow; fruits flattened; Alaska, British Columbia, Washington, Yukon.		93 Draba ruaxes (in part)
11 (9)	Rachises often slightly flexuous; petals 2-3.5 × 1-1.5 mm; fruits linear to narrowly lanceolate or narrowly oblong, slightly twisted or plane.		57 Draba lonchocarpa (in part)
+	Rachises not flexuous; petals 3-5.5 × 1.5-3.5 mm; fruits ovate, oblong, lanceolate, or broadly so, rarely narrowly lanceolate, plane		(12)
12 (11)	Fruits 3-5 mm wide; fruiting pedicels often curved upwards; leaf blade margins usually denticulate.		75 Draba oxycarpa (in part)
+	Fruits 1.5-3 mm wide; fruiting pedicels straight; leaf blade margins usually entire, rarely denticulate (D. lactea)		(13)
13 (12)	Petals white; fruits 4-8 mm, valves glabrous.		55 Draba lactea (in part)
+	Petals yellow; fruits 5-11 mm, valves pubescent.		96 Draba scotteri
14 (1)	Ovules (16-)18-36 per ovary		(15)
+	Ovules 4-14(-16) per ovary		(20)
15 (14)	Styles (0.8-)1.2-3.5 mm; racemes 12-43-flowered; s California.		95 Draba saxosa (in part)
+	Styles 0.01-0.7 mm; racemes 2-12(-23)-flowered; Alaska, Canada, Greenland		(16)
16 (15)	Fruits linear to linear-elliptic, (8-)10-17(-20) × 1.5-2 mm; plants not cespitose, caudex simple.		108 Draba stenoloba (in part)
+	Fruits oblong, ovate, or lanceolate, 4-12 × 2-5.5 mm; plants often cespitose, caudex branched		(17)
17 (16)	Leaf blade margins entire		(18)
+	Leaf blade margins dentate or denticulate		(19)
18 (17)	Petals 4-6 × 3-5 mm; fruits 3.5-5.5 mm wide (stigmas distinctly wider than styles); racemes not elongated (corymbose) in fruit.		27 Draba corymbosa (in part)
+	Petals 2-3 × (0.7-)1-1.5 mm; fruits 2-3.2 mm wide (stigmas narrower than styles); racemes mostly elongated in fruit.		62 Draba micropetala (in part)
19 (17)	Fruits oblong to lanceolate-elliptic, 4-8 × 2-3 mm; fruiting pedicels straight, suberect to ascending, often subappressed to rachises; petals white, 2.5-4 mm.		69 Draba norvegica (in part)
+	Fruits ovate to ovate-oblong, 5-10 × 3-5 mm; fruiting pedicels curved upwards, subhorizontal to divaricate-ascending, not appressed to rachises; petals yellow or creamy white, 3.5-5 mm.		75 Draba oxycarpa (in part)
20 (14)	Fruits inflated (at least basally), usually ovoid, subglobose, or ellipsoid, rarely lanceolate		(21)
+	Fruits flattened, ovate, lanceolate, oblong, or elliptic		(25)
21 (20)	Leaf blades (1-)2-4(-6) mm wide; fruit valves glabrous or pubescent, trichomes simple and 2(-4)-rayed		(22)
+	Leaf blades 0.5-1.5 mm wide; fruit valves pubescent, trichomes 2-6-rayed		(23)
22 (21)	Racemes 3-10(-13)-flowered; fruiting pedicels horizontal to divaricate, curved, glabrous (at least adaxially); ovules 10-16 per ovary; Alaska, Alberta, British Columbia, Montana, Yukon.		59 Draba macounii (in part)
+	Racemes (5-)9-18(-23)-flowered; fruiting pedicels divaricate-ascending, usually straight, rarely curved, pubescent; ovules (4-)8-12 per ovary; sc Utah.		103 Draba sobolifera (in part)
23 (21)	Adaxial surface of leaf blades with simple and 4-6-rayed trichomes; fruit valves with 4-rayed trichomes (some rays spurred).		115 Draba trichocarpa (in part)
+	Adaxial surface of leaf blades with simple and 2-rayed trichomes; fruit valves with 2-6-rayed and simple trichomes		(24)
24 (23)	Fruits (2.5-)3-4(-5) × 1.5-3.5 mm; petals bright yellow, 2-3.5(-4) mm; styles 0.2-0.6(-0.8) mm.		70 Draba novolympica (in part)
+	Fruits (5-)6-9 × (3-)3.7-5 mm; petals pale yellow, (4-)5-6 mm; styles (0.6-)0.8-1.2 mm.		79 Draba paysonii (in part)
25 (20)	Abaxial surface of leaf blades with only 2-rayed trichomes.		56 Draba lemmonii (in part)
+	Abaxial surface of leaf blades glabrous or with 2-4-rayed and simple trichomes		(26)
26 (25)	Adaxial surface of leaf blades pubescent with simple and 2-4-rayed trichomes		(27)
+	Adaxial surface of leaf blades glabrous (at least proximally), usually pubescent distally with simple trichomes		(29)
27 (26)	Styles (0.8-)1.2-3.5 mm; petals linear-oblanceolate, 0.5-1 mm wide; racemes 12-43-flowered; s California.		95 Draba saxosa (in part)
+	Styles 0.2-0.9(-1.1) mm; petals obovate, 2-3.5 mm wide; racemes 2-10 (-14)-flowered; Alaska, Canada, Greenland, Washington		(28)
28 (27)	Racemes (corymbose) not or slightly elongated in fruit; fruits 6-12 mm; seeds 1-1.3 × 0.6-0.9 mm.		27 Draba corymbosa (in part)
+	Racemes elongated in fruit; fruits 4-8(-10) mm; seeds 1.5-2 × 1-1.3 mm.		93 Draba ruaxes (in part)
29 (26)	Styles 0.3-0.6(-1) mm; petals pale yellow, 2-5 mm; leaf blades each with prominent midvein.		35 Draba densifolia
+	Styles (0.8-)1-4.5 mm; petals white, 4.5-6.5 mm; leaf blades each with obscure midvein		(30)
30 (29)	Styles (0.8-)1-1.7(-2) mm; leaf blades oblong-linear to narrowly oblanceolate, 1-2 mm wide; anthers ovate, 0.5-0.6 mm; c Idaho.		45 Draba hitchcockii
+	Styles (1.2-)2-4(-4.5) mm; leaf blades oblanceolate to obovate, 1.5-3.5 mm wide; anthers oblong, 0.8-1 mm; s Nevada.		51 Draba jaegeri