This section is from the book "A Manual Of Weeds", by Ada E. Georgia. Also available from Amazon: A Manual Of Weeds.
Native. Perennial. Propagates by seeds.
Time of bloom: May to June.
Seed-time: Late June to August.
Range: Maine and Ontario to Minnesota, southward to the Gulf of Mexico. Habitat: Dry, sandy soil; meadows, woodland borders, waste places.
A beautiful plant, often cultivated in eastern gardens. It is very commonly called Sun Dial because the leaves always face that luminary, the leaflets sometimes rotating ninety degrees on their own axes; and at night they take a position as if for sleep, folding downward around the stem. The roots penetrate the soil to a great depth, finding moisture to keep the plant green and flourishing, even in late summer when neighboring plants suffer from drought. (Fig. 161.)
Stems erect, rather stout and succulent, slightly hairy, ten to eighteen inches tall. Leaves lifted on long, slim petioles; pal-mately compound, with seven to eleven softly downy, sessile leaflets, widest near the tip and tapering to the base, the midrib of each extending beyond the tip in a minute, bristly point. Flowers numerous and very showy, on long terminal racemes, the corollas purplish blue, sometimes white; shaped like pea-blossoms, with standard turned backward at the sides, the wings united and enclosing the small, curved keel; stamen tube not cleft, its anthers of two forms; style incurved; calyx two-lipped and deeply toothed. Pods broad, flat, very hairy, about an inch and a half long, two-valved, splitting in spiral coils at maturity and flinging to some distance the four or five seeds contained; these have long vitality, often remaining dormant in the soil for many years. The seeds are also said to be very unwholesome for grazing animals, though not so dangerously harmful as those of its western relatives.
Fig. 161. - Wild Lupine (Lupinus perennis). X 1/4.
Prevent seed development by cutting before the first flowers mature. Hay containing Lupines is wholesome if it contains no ripe seeds. The perennial roots may be destroyed by cultivation of the land, which should be put to a well-fertilized and well-tilled hoed crop before reseeding with clover or grass.
 
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