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Western Wetland Flora

Field Office Guide to Plant Species

American Purple Vetch
Vicia americana Muhl. ex Willd.

JPG -- Species Photo JPG -- Distribution Map

Family: Pea (Leguminosae)
Flowering: May-August
Field Marks: This vetch is distinguished by its racemes of only 2-10 flowers and its large flowers 1/2-1 inch long.
Habitat: Along streams, damp thickets, prairies, roadsides, open places.
Habit: Sprawling perennial vine, sometimes scrambling over other vegetation.
Stems: Sprawling or climbing, up to 3 feet long, smooth or sometimes hairy.
Leaves: Alternate, pinnately compound, with 4-16 leaflets and a branched tendril where a terminal leaflet should be; leaflets linear to oblong to ovate, up to 2 inches long, rounded but with a small projection at the tip, with or without teeth,
Flowers: Flowers 2-9 in racemes from the axils of the leaves, the racemes on stalks shorter than the leaves.
Sepals: 5, united below, green, the tube up to 1/4 inch long, the teeth very unequal in size and shape.
Petals: 5, purple, up to 1 inch long, with the configuration of a sweetpea flower.
Stamens: 10.
Pistils: Ovary superior, smooth.
Fruits: Pods up to nearly 2 inches long, up to nearly 1/2 inch wide, smooth, containing 8-14 seeds; seeds black, 1/6-1/4 inch in diameter.
Notes: There is considerable variation in leaflet size and number.

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Page Last Modified: Saturday, 02-Feb-2013 06:26:50 EST
Menlo Park, CA [caww55]