1911 Encyclopædia Britannica/Lupine

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LUPINE (Lupinus), in botany, a genus of about 100 species of annual and perennial herbaceous plants of the tribe Genisteae, of the order Leguminosae. Species with digitate leaves range along the west side of America from British Columbia to northern Chile, while a few occur in the Mediterranean regions. A few others with entire leaves are found in Brazil and eastern North America. The leaves are remarkable for “sleeping” in three different ways. From being in the form of a horizontal star by day, the leaflets either fall and form a hollow cone with their bases upwards (L. pilosus), or rise and the cone is inverted (L. luteus), or else the shorter leaflets fall and the longer rise, and so together form a vertical star as in many species; the object in every case being to protect the surfaces of the leaflets from radiation and consequent wetting with dew (Darwin, Movements of Plants, p. 340). The flowers are of the usual “papilionaceous” or pea-like form, blue, white, purple or yellow, in long terminal spikes. The stamens are monadelphous and bear dimorphic anthers. The species of which earliest mention is made is probably L. Termis, which was cultivated by the ancient Egyptians. It is wild in some parts of the Mediterranean area and is extensively cultivated in Egypt. Its seeds are eaten by the poor after being steeped in water to remove their bitterness; the stems furnish fuel and charcoal for gunpowder. The lupine of the ancient Greeks and Romans was probably L. albus, which is still extensively cultivated in Italy, Sicily and other Mediterranean countries for forage, for ploughing in to enrich the land, and for its round flat seeds, which form an article of food. Yellow lupine (L. luteus) and blue lupine (L. angustifolius) are also cultivated on the European continent as farm crops for green manuring.

Lupines are easily cultivated in moderately good garden soil; they include annuals which are among the most ornamental and most easily grown of summer flowering plants (sow in open borders in April and May), and perennials, which are grown from seed or propagated by dividing strong plants in March and April. Many of the forms in cultivation are hybrid. One of the best known of the perennial species is L. polyphyllus, a western North American species. It grows from 3 to 6 ft. high, and has numerous varieties, including a charming white-flowered one. The tree lupine (L. arboreus) is a Californian bush, 2 to 4 ft. high, with fragrant yellow flowers. It is only hardy in the most favoured parts of the kingdom.