Lupinus pusillus

Lupinus pusillus, the rusty lupine or dwarf lupine, is an annual plant in the legume family (fabaceae) found in the Colorado Plateau and Canyonlands region of the southwestern United States(California), and north to Montana.

Lupinus pusillus
Lupinus pusillus, Montana
Conservation status
Secure (NatureServe)
Scientific classification
Kingdom:	Plantae
Clade:	Embryophytes
Clade:	Tracheophytes
Clade:	Spermatophytes
Clade:	Angiosperms
Clade:	Eudicots
Clade:	Rosids
Order:	Fabales
Family:	Fabaceae
Subfamily:	Faboideae
Genus:	Lupinus
Species:	L. pusillus
Binomial name
Lupinus pusillus Pursh

Lupinus pusillus in the Wyoming big sagebrush steppe biome, near Phillips, Montana.

Description

Growth pattern

It is an annual plant growing up to 9 inches (23 cm) tall. Pusillus is for the small size of the plant.

Leaves and stems

Leaves are compound palmate with 3-9 1⁄2 to 1+1⁄2 inches (1.3 to 3.8 cm) long inversely lance- shaped leaflets.

Plant stems and leaf stems (petioles) have long spreading hairs.

Inflorescence and fruit

It blooms from April to June.

Flowers are in stalks of 4-38 and bluish to purple or bicolored, with a yellow spot on the upper petal.

Seedpods are nearly oval and have constrictions separating the seeds.

Habitat and range

It can be found in desert shrubland and pinyon juniper woodland communities, from as far north as Washington, to California, and throughout the southwest.

When growing in reddish sand, the blue flowers make a striking contrast with the sun at a low angle.

Ecological and human interactions

It is pollinated by bees.