''Lupinus rivularis'' is a species of lupine known by the common name riverbank lupine native to North America. It is also commonly known as river lupine, streambank lupine, and stream lupine.Darris, D.; Young-Mathews, A. Plant Fact Sheet for Riverbank Lupine (Lupinus rivularis); USDA NRCs Plant Materials Center: Corvallis, OR, USA, 2012.

Distribution

''Lupinus rivularis'' is found in western North America, from southern

British Columbia British Columbia (commonly abbreviated as BC) is the westernmost province of Canada, situated between the Pacific Ocean and the Rocky Mountains. It has a diverse geography, with rugged landscapes that include rocky coastlines, sandy beaches, ...

to northern

California California is a U.S. state, state in the Western United States, located along the West Coast of the United States, Pacific Coast. With nearly 39.2million residents across a total area of approximately , it is the List of states and territori ...

. Specifically, it is native to California, Oregon, Washington, and British Columbia. It mainly exists from coastal habitat in places such as both

Olympic Olympic or Olympics may refer to Sports Competitions * Olympic Games, international multi-sport event held since 1896 ** Summer Olympic Games ** Winter Olympic Games * Ancient Olympic Games, ancient multi-sport event held in Olympia, Greece b ...

and Redwood National Parks, and at

Point Reyes National Seashore Point Reyes National Seashore is a park preserve located on the Point Reyes Peninsula in Marin County, California. As a national seashore, it is maintained by the US National Park Service as an important nature preserve. Some existing agricult ...

. Its development in these regions is driven by its preference for sandy, well-drained, and low nitrogenous soils, along with precipitation levels between 20 and 100 inches. Additionally, this species observes optimal growth in environments with full sunlight. Riverbank lupine is able to well establish a population where there is reduced competition, making it an excellent pioneer species for disturbed environments.

Description

This is a robust, erect perennial herb or

subshrub A subshrub (Latin ''suffrutex'') or dwarf shrub is a short shrub, and is a woody plant. Prostrate shrub is a related term. "Subshrub" is often used interchangeably with "bush".Jackson, Benjamin, Daydon; A Glossary of Botanic Terms with their Der ...

growing up to about a meter tall ]. The long taproot enables its growth in dry soil environments that are typical of disturbed botanical environments. The mostly hairless stem is thick, hollow, and reddish in color. Each alternate, palmately compound leaf is made up of 5 to 9 wide leaflets long. The

inflorescence An inflorescence is a group or cluster of flowers arranged on a stem that is composed of a main branch or a complicated arrangement of branches. Morphologically, it is the modified part of the shoot of seed plants where flowers are formed o ...

is a

raceme A raceme ( or ) or racemoid is an unbranched, indeterminate type of inflorescence bearing flowers having short floral stalks along the shoots that bear the flowers. The oldest flowers grow close to the base and new flowers are produced as the s ...

of many

flower A flower, sometimes known as a bloom or blossom, is the reproductive structure found in flowering plants (plants of the division Angiospermae). The biological function of a flower is to facilitate reproduction, usually by providing a mechani ...

s sometimes arranged in whorls. The flower is light purple in color, often with white parts or shading. The

fruit In botany, a fruit is the seed-bearing structure in flowering plants that is formed from the ovary after flowering. Fruits are the means by which flowering plants (also known as angiosperms) disseminate their seeds. Edible fruits in particu ...

is a somewhat hairy

legume A legume () is a plant in the family Fabaceae (or Leguminosae), or the fruit or seed of such a plant. When used as a dry grain, the seed is also called a pulse. Legumes are grown agriculturally, primarily for human consumption, for livestock f ...

pod up to long which turns dark as it ages. The seed pods house 6-10 seeds and are coated in sparsely distributed hairs. Riverbank lupine also has a distinct aroma that stimulates the attraction of its pollinators. The bloom occurs from March to July, lasting approximately two to four weeks.

Conservation status

In British Columbia, riverbank lupine is considered endangered due to genetic breeding with other lupine species, loss of habitat, predation, pesticide use, and a multitude of other factors. However, its distribution is fairly stable throughout the rest of its range of distribution.

Uses

Riverbank lupine has a range of important applications and uses, such as erosion control, food for wildlife, ornamental decorations, medicinal usage, and cover crops. As a pioneer species, it is capable of mass growth, thus is ideal for renewal of sites that have undergone erosion. This is enabled through their nitrogen fixation abilities, which makes them very effective at promoting revegetation and reforestation. The seeds produced by riverbank lupine serve as a food source for many birds, while other species rely on the abundant vegetation as a site of cover. Additionally, the low alkaloid content in riverbank lupine makes it suitable for livestock grazing. The showy nature of the floral arrangement makes riverbank lupine ideal for ornamental display in certain environmental landscapes. Lastly, the Thompson Indians of British Columbia reportedly utilized riverbank lupine in a variety of medicinal applications.

References

External links

Jepson Manual TreatmentTurner PhotographicsPhoto gallery
{{Authority control rivularis Flora of British Columbia Flora of the West Coast of the United States Flora without expected TNC conservation status