Draft Key to Astragalus of the Wasatch Mountains and Bear River Range

1	Plants low-growing, either mat-forming, prostrate, acaulescent to subacaulescent, with stems to 20 (35) cm long; leaflets strigose to densely pubescent on one or both sides.	2
1	Plants more or less erect and while occasionally very small, plants caulescent; leaflets most often glabrous to strigose (A. drummondii leaflets villous-pilose below and A. lentiginosus leaflets glabrous to pubescent on one or both sides).	11
2 (1)	Leaves with 5-7 spinulose-tipped leaflets; our variety prostrate, of alpine or subalpine, often barren habitats within our area, in Cache, Salt Lake, Utah, and Wasatch Counties.	Spiny Milkvetch A. kentrophyta var. tegetarius
2	Leaves not spine-tipped; plants of various habitats and distribution within our area.	3
3 (2)	Leaves simple or 3-foliate; silvery strigose with dolabriform [1] pubescence.	4
3	Leaves plurifoliate; pubescence basifixed or dolabriform.	5
4 3)	Leaves 3-foliate; flowers 17-24 mm long, often appearing below, or on short pedicels close to the leaves; flowers white to ochroleucous [2]; pods 6-10 mm long, strigose to densely hairy; in our area plants typically occur in the foothills and other areas below 7,000 ft elevation on the east side of the Bear River Range in Rich County.	Plains Milkvetch A. gilviflorus
4	Leaves all or mostly simple, reduced to a flattened leafstalk that functions as a leaf, only rarely with 3-5 leaflets on some leaves; flowers 5.5-9.5 mm long, flowers pink-purple or whitish to ochroleucous; pods 4-13 mm long, strigose to rarely glabrous; occasional in our area, reported in Cache County and found in the foothills on the east side of the Bear River Range in Rich County.	Tufted Milkvetch A. spatulatus
5 (3)	Flowers pink-purple, 5-7 mm long; leaves with 9-15 small (1-5 mm) linear to narrowly elliptic leaflets; inflated pods 10-17 mm long, 7-11 mm thick, mottled, and strigose; plants on rocky slopes and ridge tops in sagebrush, rabbitbrush, and open pinyon-juniper communities of Bear Lake and Rich County (lower east foothills of the Bear River Range).	Starveling Milkvetch A. jejunus var. jejunus
5	Flowers 15 mm or greater in length; other features variable.	6
6 (5)	Pods villous-hirsute to long, shaggy villous	7
6	Pods strigose or rarely with very small, soft straight hairs	10
7 (6)	Leaflets densely villous to densely villous-tomentose above and below; plants of Utah and other nearby states	8
7	Leaflets silvery strigose to strigulose-villosulous; plants endemic to Utah	9
8 (7)	Leaflets obovate or suborbicular to ovate; pods lance-ellipsoid or narrowly ovoid-acuminate, body about 3-4 times longer than wide, nearly straight; plants widespread throughout our area and throughout much of Utah, eastern Nevada, and portions of Idaho and possibly Oregon.	Utah Milkvetch A. utahensis
8	Leaves elliptic to oblanceolate; pods obliquely ovoid, body more or less twice as long as wide, usually curved; plants widespread in the western States, but found only in Franklin County, Idaho and Rich County, Utah in our area.  Two varieties distinguished below: ·   var. glareosus with pink-purple flowers ·   var. purshii with whitish to ochroleucous flowers	Woolypod Milkvetch A. purshii
9 (7)	Flowers 18-23 mm long; calyx tube 6.2-7.5 mm long; pods 10-20 mm, densely hirsute with lustrous hairs; plants limited in their distribution to one population on the Moroni Formation (ash-flow tuff) in Utah County.	Deseret Milkvetch A. desereticus
9	Flowers 22-28 mm long; calyx tube 8.5-10.5(12) mm long; pods 15-40 mm long, villous hirsute; plants endemic to much of western Utah and found in our area in both Utah and Wasatch Counties.	Eureka Milkvetch A. eurekensis
10 (6)	Flowers white; leaflets widely elliptical, green with short, strigulose, dolabriform hairs; plants known from only 2 populations (2015) in openings in oak woodlands at about 5,300 ft elevation on the lower foothills in Weber County, just east of Ogden.	Kelsey Milkvetch A. kelseyae
10	Flowers dull to bright pink-purple or pale; leaflets elliptical, pilose above and below with basifixed hairs; plants widespread in our area; two varieties distinguished below: ·   var. argophyllus occurs in meadows, along streambanks and lake shore and has bright pink-purple flowers 22-26 mm long ·   var. martini occurs in sagebrush and mountain brush communities and has dull pink-purple or pale flowers 18-22.5 mm long.	Silverleaf Milkvetch A. argophyllus
11 (1)	Uppermost leaves reduced to the rachis; leaflets, when present 3-13; flowers white to light yellow, 6.5-12 mm long, often with purple veins; pods more or less linear, laterally compressed, and strigose, 13-50 mm long; plants widespread in our area in pinyon-juniper, sagebrush, mountain brush, and aspen communities.	Lesser Rushy Milkvetch A. convallarius
11	Leaves and leaflets much more discernable; flowers, pods and distribution variable	12
12 (11)	Flowers pink-purple to dark lavender (some species also key under the next category because they can have flowers that fall into those colors).	13
12	Flowers white, cream, to ochroleucous, occasionally with purple veins	15
13 (12)	Pods silky villous, 7-10 mm long; leaflets narrowly elliptic to lance-oblong; flowers pink-purple; calyx tubes villous; typically sod-forming in seasonally moist sites in the northern portion of our area (Franklin and Bear Lake Counties, Idaho and Cache and Rich Counties, Utah) and the southern portion of our area (Utah and Wasatch Counties, Utah).	Purple Milkvetch A. agrestis
13	Pods glabrous to strigose or sparsely short-hairy; leaflets elliptic to ovate, obovate, oblanceolate, to lanceolate; flowers pale pink to deep lavender; calyx tubes strigose; plants not sod-forming, occurring on a variety of sites in varying distributions.	14
14 (13)	Flowers 15-19 mm long, pink-purple with white wing tips; calyx strigose, typically darkened with short black hairs; pods glabrous to short hairy with black and white hairs; plants distributed throughout our area (not noted in Morgan County, but expected there as well) in mixed desert shrub, pinyon-juniper, sagebrush, and mountain brush communities.	Browse Milkvetch A. cibarius
14	Flowers 9-16 mm long, pale pink to pink-purple, but lacking white wing tips; calyx strigose, occasionally with only scattered short black hairs; plants found below 7,000 ft in pinyon-juniper, sagebrush, and mountain brush communities in Bear Lake County, Idaho and Rich County, Utah in our area.	Freckled Milkvetch A. lentiginosus var. chartaceus (platyphyllidus)
15 (12)	Flowers small, 11 mm long or less (Astragalus lentiginosus var. chartaceus keys here as well as in next couplet)	16
15	Flowers larger, greater than 11 mm long	18
16 (15)	Pods more or less inflated; calyx tubes 3-9 mm, cylindric to short cylindric (two varieties): ·   var. salinus has flowers less than 9 mm long, pods that are transparent to translucent (Morgan and Wasatch Counties, UT) ·   var .chartaceus (platyphyllidus) has flowers 9-16 mm long (keys below as well); pods stiffly papery to leathery, opaque or nearly so (Rich County, UT and Bear Lake County, ID).	Freckled Milkvetch A. lentiginosus
16	Pods not inflated; calyx tubes less than 3 mm, campanulate	18
17 (16)	Pods laterally flattened, elliptic to oblong, glabrous to less often strigose, subsessile or on stipes to 5.5 mm long; flowers white to ochroleucous, may be purple-veined; leaflets glabrous above and thinly strigose, to strigose on the margins and below; found in Bear Lake and Cache Counties in the north and Utah and Wasatch Counties in the south.	Looseflower Milkvetch A. tenellus
17	Pods narrowly oblong or oblanceolate, rounded (not laterally flattened), strigose, sessile or nearly so; flowers white to cream (often purple-veined) with purple keel tip; leaflets strigose above and below. (two varieties): ·   var. tenuifolius has 3-11 leaflets; flowers 6-8 mm long, + widely spaced; pods narrowly oblong (Cache, Rich, and Wasatch Counties in our area) ·   var. oblongifolius has11-21 leaflets; flowers 8-11 mm long, initially compacted at raceme apex; pods oblanceolate in outline (all Utah counties except Davis and Morgan in our area)	Timber Milkvetch A. miser
18 (15)	Pods pilose to silky villous	19 A. cicer pods
18	Pods glabrous to strigose	20 A. cibarius pods
19 (18)	Flowers 17-24 mm; pods oblong-ellipsoid, 7-10 mm long, 3-4 mm wide, more or less 3-sided (lower deeply groved); typically sod-forming in seasonally moist sites; in the northern portion of our area (Franklin and Bear Lake Counties, ID and Cache County, UT) and the southern portion of our area (Utah and Wasatch Counties, UT).	Purple Milkvetch A. agrestis
19	Flowers dense (10-30 flowers per raceme), erect, less than 17 mm; ; plants with basifixed hairs; pods subsessile, spreading, ovoid or sub-globose, pilose, 6-14 mm long, 6-10 mm wide; introduced forage plant in Morgan, Rich, Salt Lake, Utah and Wasatch Counties in our area.	Chickpea Milkvetch A. cicer
20 (18)	Pods strigose	21
20	Pods glabrous	22
21 (20)	Flowers 9-16 mm long; pods more or less inflated, 12-26 mm long, 5-10 mm wide; plants found below 7,000 ft in pinyon-juniper, sagebrush, and mountain brush communities in Bear Lake County, ID and Rich County, UT in our area.	Freckled Milkvetch A. lentiginosus var. chartaceus (platyphyllidus)
21	Flowers 15-19 mm long; pods ellipsoid to oblong, straight to curved, woody or stiffly leathery; plants widespread throughout our area in mountain brush, sagebrush, pinyon-juniper, and desert shrub communities.	Browse Milkvetch A. cibarius
22 (20)	Pods not inflated	23
22	Pods more or less inflated	24
23 (22)	Pods laterally compressed; plants in our area from Utah County and near Strawberry Reservoir in Wasatch County.	Drummond’s Milkvetch A. drummondii
23	Pods triquetrous, grooved on bottom; plants of Utah and Wasatch Counties in our area in pinyon-juniper, sagebrush, mountain brush, aspen, and conifer communities.	Rocky Mountain Milkvetch A. scopulorum
24 (22)	Plants occurring in moist meadow or riparian habitats; racemes many-flowered, flowers spreading declined; raceme 2.5-16 cm in fruit; plants with dolabriform hairs; pods sessile or subsessile, erect, cylindroid, glabrous or pubescent, 10-20 mm long, 2.9-5.2 mm wide; in Cache, Rich, Salt Lake, Utah, and Wasatch Counties in our area. Two varieties occur in our area: ·   var. canadensis has glabrous, terete (not dorsally furrowed) pods, and is typically 4-12 dm tall; (Cache, Rich, and Salt Lake Counties) ·   var. brevidens has pubescent, dorsally furrowed pods, and is typically 1.5-5 dm tall; (Cache, Rich, Salt Lake, Utah and Wasatch Counties)	Canadian Milkvetch A. canadensis
24	Plants generally smaller, occurring in drier sagebrush, mountain brush, and pinyon-juniper habitats	25
25 (24)	In our area, plants of Bear Lake County, Idaho and Rich County, Utah.	Freckled Milkvetch A. lentiginosus var. chartaceus (platyphyllidus)
25	In our area, plants of Morgan County south to Utah County, Utah	26
26 (25)	Pods inflated (not bladdery), crescent-shaped, 15-37 mm long; plants more widespread, occur in Davis, Morgan, Salt Lake, Utah, and Weber Counties County (plants in flower without fruit are very difficult to distinguish from the following species; pods are generally required and are very similar in appearance).	Beckwith’s Milkvetch A. beckwithii var. beckwithii
26	Pods bladdery inflated, ellipsoid (not crescent shaped), 25-55 mm long; plants in our area have been noted to occur only in Utah County, but populations have not recently been relocated.	Egg Milkvetch A. oophorus var. caulescens

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[1] Dolabriform = straight appressed hairs attached by the middle, spreading to free tips

[2] Ochroleucous = Yellowish-white

Draft Key © Wayne Padgett, Wasatch Ecology, LLC