Al Schneider's Rocky Mountains Plant Descriptions

Western Sweetvetch
Hedysarum occidentale
Pea family (Fabaceae)

This intensely pink-purple pea is characterized by widely spaced , segmented seed pods, upper shorter than lower ones, and leafless flower stems. Hedysarum occidentale varies from just a foot tall to robust shrub-like plants three feet tall and wide. This species is very similar to H. boreale (found at lower elevations) and is distinguished by minute characteristics, such as, the markings on loments (the seed pods), the size of the , and the leaf . H. occidentalis also grows to a much larger size.

Linnaeus named this in 1753. "Hedysarum" is a name given thousands of years ago by Theophrastus to some member of the Pea Family and "occidentalis" is Greek for "western." Charles Piper collected Hedysarum occidentale in 1890 and Edward Greene named and described the plant in 1896.


© Mary Ellen (Mel) Harte, Bugwood.org

Description

Long-lived with stems to over 3' tall from a branching (woody base of non-woody ). Stems erect. Leaves to 8" long. 11-19, 1/3 to 1 1/2" long, hairy both sides or above. from 1 1/2" to 6" long. 10-50 flowered, flowers spreading to declined, pink to red-purple. are pods (loments), , flattened, constricted between seeds.

Field Marks

Shrub-like pea with numerous stems of hot pink flowers.

© Al Schneider

A raceme is an unbranched, indeterminate type of inflorescence bearing flowers having short floral stalks along its axis.

A peduncle is a common stalk of a cluster of flowers.

A perennial plant lives and blooms for many years.

venation -- The arrangemnet of veins in a leaf.

lobe -- A rounded parts of a leaf (or other organ).

Usually green, sepals typically function as protection for the flower in bud, and often as support for the petals when in bloom.

calyx -- the sepals of a flower, typically forming a whorl that encloses the petals and forms a protective layer around a flower in bud.

fruit -- any seed-bearing structure in flowering plants. It is formed from the ovary after flowering.

hanging or drooping.

caudex -- The woody stem base of some herbaceous perennials.

genus -- A subdivision of a botanical Family in which all members have a significant number of similar characteristics.

glabrous -- smooth, glossy, having no bristles or hair-like structures. Bald.

leaflets -- Each little leaf-like thing in a compound leaf is a leaflet.