6a. Branches glabrous or nearly so (tree; flowers white) =Black Locust, Robinia pseudo-acacia.=

6b. Branches glandular-p.u.b.escent (tall shrub; flowers pinkish) =Clammy Locust, Robinia viscosa.=

6c. Branches bristly (shrub. 1-3 m. high; flowers pink) =Bristly Locust, Robinia hispida.=

7a. Trees; leaves 2-3-pinnate (flowers greenish-white, spring) =Kentucky Coffee-tree, Gymnocladus dioica.=

7b. Low shrubs; leaves once-pinnate (3-6 dm. high; summer) --8.

8a. Flowers bright-blue, each with a single petal =Lead Plant, Amorpha canescens.=

8b. Flowers yellowish and pink-purple, petals 5 --26a.

9a. Leaflets 5-7; flowers in racemes (purplish, late summer) =Wild Bean, Apios tuberosa.=

9b. Leaflets 3 (flowers greenish, purple, or white, late summer) --10.

10a. Flowers in small capitate cl.u.s.ters; lower 2 petals strongly incurved =Wild Bean, Strophostyles helvola.=

10b. Flowers in racemes (Hog Peanut) --11.

11a. Stem p.u.b.escent or glabrate; leaflets seldom more than 5 cm. long =Hog Peanut, Amphicarpa monoica.=

11b. Stem villous with retrorse hairs; leaflets usually longer than 5 cm.

=Hog Peanut, Amphicarpa pitcheri.=

12a. Style with a tuft of hairs at the apex; lateral petals of the corolla adherent to the lower ones as far as the middle; stipules less than 10 mm. long, and usually less than one-fourth the length of the lower leaflets (spring and summer) (Vetch) --13.

12b. Style hairy along the inner side; lateral petals of the corolla free from the lower ones or adherent only at the very base; stipules more than 8 mm. long and usually one-third or more the length of the lower leaflets (late spring and summer) --17.

13a. Flowers axillary, sessile or nearly so (flowers purple) --14.

13b. Flowers in peduncled racemes --15.

14a. Upper leaves oblong-obovate, truncate or notched, and mucronate at the apex =Spring Vetch, Vicia sativa.=

14b. Upper leaves lance-linear, sharply acute =Common Vetch, Vicia angustifolia.=

15a. Flowers 15-20 mm. long, 4-8 in a cl.u.s.ter (flowers purple) =Vetch, Vicia americana.=

15b. Flowers 8-12 mm. long --16.

16a. Racemes one-sided; flowers blue =Vetch, Vicia cracca.=

16b. Racemes loosely flowered, not one-sided; flowers whitish, the lower petals tipped with blue =Vetch, Vicia caroliniana.=

17a. Flowers yellowish-white =Vetchling, Lathyrus ochroleucus.=

17b. Flowers purple --18.

18a. Stipules nearly regularly halberd-shape, almost as large as the leaflets =Beach Pea, Lathyrus maritimus.=

18b. Stipules half-sagittate, apparently attached laterally near the middle --19.

19a. Leaflets 4-8 pairs, ovate; racemes with 10 or more flowers =Wild Pea, Lathyrus venosus.=

19b. Leaflets 2-4 pairs, linear to oblong or elliptical; racemes with 2-9 flowers (Marsh Pea) --20.

20a. Stems with a membranous wing on the margins =Marsh Pea, Lathyrus pal.u.s.tris.=

20b. Stems angled, but not winged =Marsh Pea, Lathyrus pal.u.s.tris var. myrtifolius.=

21a. Leaves simple (2-3 dm. high; flowers yellow, summer) =Rattlebox, Crotalaria sagittalis.=

21b. Leaves palmately compound; leaflets 7-11 (3-6 dm. high; flowers blue, late spring) =Lupine, Lupinus perennis.=

21c. Leaves pinnately compound; leaflets 5 to many --22.

21d. Leaves compound; leaflets 3 --28.

22a. Leaflets 5; flowers rose-purple in a spike-like head (5-8 dm.

high, late summer) =Prairie Clover, Petalostemum purpureum.=

22b. Leaflets more than 5 --23.

23a. Flowers bright-blue, in a dense spike (3-6 dm. high; summer) --8a.

23b. Flowers bright-yellow; stamens not united (summer) --24.

23c. Flowers white, cream-color, or yellowish, or marked with purple --26.

24a. Leaflets linear-oblong, 2 cm. long or less; stamens 5 or 10 (3-6 dm. high) (Partridge Pea) --25.

24b. Leaflets lanceolate-oblong, 2-5 cm. long; 7 stamens with normal anthers and 3 with imperfect anthers (8-15 dm. high) =Wild Senna, Ca.s.sia marilandica.=

25a. Anthers 10; flowers 2-4 cm. wide =Partridge Pea, Ca.s.sia chamaecrista.=

25b. Anthers 5; flowers 5-10 mm. wide =Partridge Pea, Ca.s.sia nict.i.tans.=

26a. Silky-hairy with whitish hairs; flowers marked with purple (3-5 dm. high; summer) =Goat's Rue, Tephrosia virginiana.=

26b. Glabrous or nearly so (summer) (Milk Vetch) --27.

27a. Flowers greenish cream-color (4-10 dm. high) =Milk Vetch, Astragalus canadensis.=

27b. Flowers white (3-5 dm. high) =Milk Vetch, Astragalus neglectus.=

28a. Flowers in heads, umbels, or short dense spikes --29.