Lupinus pusillus

Lupinus pusillus
Lupinus pusillus, Montana
Conservation status
Secure  (NatureServe)[1]
Scientific classification
Kingdom:	Plantae
Clade:	Tracheophytes
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.

Lupinus pusillus, the rusty lupine[2] 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),[3]: 159  and north to 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.[3]: 159 

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.[3]: 159 

Plant stems and leaf stems (petioles) have long spreading hairs.[3]: 159 

Inflorescence and fruit

It blooms from April to June.[3]: 159 

Flowers are in stalks of 4-38 and bluish to purple or bicolored, with a yellow spot on the upper petal.[3]: 159 

Seedpods are nearly oval and have constrictions separating the seeds.[3]: 159 

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.[3]: 159 

When growing in reddish sand, the blue flowers make a striking contrast with the sun at a low angle.[3]: 159 

Ecological and human interactions

It is pollinated by bees.[3]: 159 

References

1. NatureServe (2024). "Lupinus pusillus". Arlington, Virginia. Retrieved 11 July 2024.
2. NRCS. "Lupinus pusillus". PLANTS Database. United States Department of Agriculture (USDA). Retrieved 10 May 2017.
3. Canyon Country Wildflowers, Damian Fagan, 2nd ed., 2012, Morris Bush Publishing, LLC. in cooperation with Canyonlands Natural History Association, ISBN 978-0-7627-7013-7