Astragalus alpinus
 
Alpine Milk-Vetch

Flower Top

Good Spirit Lake Provincial Park
20-June-2006

Note the black hairs on the calyx.

The authors of both Budd's Flora and Flora of Alberta evidently struggled with this species when creating their species keys.  This was likely due to the variable nature  of A. alpinus and the large number of Astragalus species found in the covered areas.  Budd's Flora branches twice to this species, while Flora of Alberta branches three times.  The key answers are sometimes partially contradictory, even within the same flora.

Alpinus:  Answers to key questions in Budd's Flora (BF) and Flora of Alberta (FOA) leading to this species.  

plants of moist habitats in the north and the mountains; NOT [plants of dry plains and foothills] (FOA)

plants with slender rootstalks; NOT [plants with taproots or caudex] (BF)

stems evident, erect or decumbent, often branched and leafy; NOT [plants densely caespitose or pulvinate; leaves many, crowded; flowers often included among leaves or barely exceeding them] (FOA)

stems prostrate or weakly ascending; NOT [stems erect] (FOA)

stems generally less than 5 mm thick at base; NOT [stem generally thick, 5-10 mm at base] (FOA)

larger stems 1.0-1.5 mm thick at base; NOT [larger stems 1.5-3.0 mm thick at base] (FOA)

plants low, stems 1-3 dm high; NOT [plants up to 6 dm high] (BF)

plants taller; NOT [plants low, 1 dm or less] (FOA)

plants 0.5-3.0 dm high; NOT [plants 2.5-6.5 dm high] (FOA)

 leaves with at least 7 leaflets; NOT [leaves usually with a single leaflet, occasionally with 3 or 5 leaflets] (BF)

leaves NOT needle-like (FOA)

leaflets shorter than 2-4 (6) cm long (FOA)

larger leaflets about 1 cm long; NOT [larger leaflets 1-2 cm long] (FOA)

leaflets rounded at the ends; NOT [leaflets mostly acute] (FOA)

leaflets NOT spine-tipped (BF)

NOT [leaves strigose above and below with basifixed hairs] (FOA)

flowers borne on more or less well developed peduncles; NOT [flowers borne in the crown of the plant] (BF)

flowers in loose racemes; NOT [flowers in dense globose or elongate heads] (FOA)

inflorescence NOT head-like, if densely flowered an elongated raceme; NOT [inflorescence a short, dense, head-like raceme, about as long as wide] (BF)

inflorescence a short, loosely flowered raceme; NOT [inflorescence a dense, head-like raceme] (BF)

NOT [flowers 10-12 (15) mm long, in a dense raceme] (FOA)

flowers spreading or pendent; NOT [flowers all erect] (BF)

flowers about 10 mm long; NOT [flowers about 15 mm long] (FOA)

flowers 10-15 mm long; NOT [flowers about 20 mm long] (FOA)

flowers 5-12 mm long; NOT [flowers 12-30 mm long] (FOA)

calyx only about a third the length of the flower; NOT [calyx almost half as long as the flower] (FOA)

calyx-teeth shorter than the calyx-tube; NOT [calyx-teeth about as long as or longer than the calyx-tube] (FOA)

calyx-teeth deltoid to lanceolate; NOT [calyx-teeth linear] (FOA)

flowers purplish to whitish purple; NOT [flowers brick red to purplish], NOT [flowers white, yellow, or greenish] (BF)

wing-petals entire; NOT [wing-petals deeply bidentate at the apex] (FOA)

keel-petals longer than 6 mm, about as long as the wings; NOT [keel-petals less than 6 mm long, much shorter than the wings] (FOA)

pod stipitate, the stipe about as long as the calyx-tube; NOT [pod short-stipitate, the stipe much shorter than the calyx-tube] (FOA)

pods reflexed; NOT [pods erect] (BF)

pods NOT inflated (BF)

NOT [pod globose, coarsely pilose with black and white hairs] (FOA)

pods black hairy; NOT [pods densely pubescent] (BF)

pods with at least some black hairs; NOT [pods glabrous or with only white hairs] (FOA)

 

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

herbs; NOT shrubs

 leafy stems often present; NOT [leafy stems usually absent]

plants NOT climbing

 leaves pinnate; NOT [palmate]

 leaves NOT glandular-dotted

 leaflets more than 3; NOT [leaflets 3 (rarely 1)]

terminal leaflet normal; NOT [terminal leaflet replaced by a tendril]

NOT [inflorescence umbel-like; flowers yellow; leaflets 5, pinnately arranged (the lower pair basal and resembling stipules]

NOT [flowers pinkish to red or purple; calyx-lobes subulate, much longer than the tube; fruit only slightly longer than wide, with short, stout spines, 1-seeded]

 keel rounded or obtuse at the tip; NOT [keel with a sharp point at the tip]

keel NOT truncate; NOT [keel mostly truncate]

 pods NOT segmented or jointed; NOT [pods segmented or jointed, breaking up at maturity]

 

Leguminosae:  Answers to key questions in Budd's Flora leading to this family.  

herbs; NOT [shrubs or trees]

plants terrestrial or semi-aquatic; NOT [plants aquatic, leaves submerged or floating]

plants NOT with colored milky juice

plants with more than one normal leaf

some or all leaves alternate; NOT [leaves opposite, whorled, or basal]

leaves with stipules

calyx regular

flowers with two floral rings, and with each petal distinct from the others

flowers irregular in shape

corolla pea-like; NOT [corolla with one petal spurred or sac-like]

stamens usually separate or partly so; NOT [stamens united into a column]

fruit a legume; NOT [fruit a 3-valved capsule]