''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 is the westernmost Provinces and territories of Canada, province of Canada. Situated in the Pacific Northwest between the Pacific Ocean and the Rocky Mountains, the province has a diverse geography, with rugged landscapes that ...

to northern

California California () is a U.S. state, state in the Western United States that lies on the West Coast of the United States, Pacific Coast. It borders Oregon to the north, Nevada and Arizona to the east, and shares Mexico–United States border, an ...

. 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 bet ...

and

Redwood National Park The Redwood National and State Parks (RNSP) are a complex of one List of national parks of the United States, United States national park and three List of California state parks, California state parks located along the coast of northern Cali ...

s, and at

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

. 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 Pioneer species are resilient species that are the first to colonize barren environments, or to repopulate disrupted biodiverse steady-state ecosystems as part of ecological succession. Various kinds of events can create good conditions for pi ...

for disturbed environments.

Description

This is a robust, erect perennial herb or

subshrub A subshrub (Latin ''suffrutex'') or undershrub is either a small shrub (e.g. prostrate shrubs) or a perennial that is largely herbaceous but slightly woody at the base (e.g. garden pink and florist's chrysanthemum). The term is often interch ...

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 In botany, an inflorescence is a group or cluster of flowers arranged on a plant's Plant stem, stem that is composed of a main branch or a system of branches. An inflorescence is categorized on the basis of the arrangement of flowers on a mai ...

is a

raceme A raceme () or racemoid is an unbranched, indeterminate growth, 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 ...

of many

flower Flowers, also known as blooms and blossoms, are the reproductive structures of flowering plants ( angiosperms). Typically, they are structured in four circular levels, called whorls, around the end of a stalk. These whorls include: calyx, m ...

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 (angiosperms) that is formed from the ovary after flowering. Fruits are the means by which angiosperms disseminate their seeds. Edible fruits in particular have long propaga ...

is a somewhat hairy

legume Legumes are plants in the pea family Fabaceae (or Leguminosae), or the fruit or seeds of such plants. When used as a dry grain for human consumption, the seeds are also called pulses. Legumes are grown agriculturally, primarily for human consum ...

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 Nlakaʼpamux 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