This section is from the book "Wild Flowers Of New York", by Homer D. House. Also available from Amazon: Wild Flowers Of New York.
Leaves and stems glabrous, especially when young, from a stout, horizontal rootstock, one-half to I inch thick, densely clothed with thick, fibrous roots. Juice of the roots and stems red. Leaves basal on petioles 6 to 14 inches long, palmately five to nine-lobed, the lobes repand or cleft at the apex and palmately veined. Flowering scapes, one-flowered, at length overtopped by the mature leaves, but at flowering time longer than the partially unfolded immature leaves. Flowers white or sometimes pinkish, 1 to 1½ inches broad; sepals two, soon falling. Petals eight to sixteen, oblong-spatulate, arranged in two or three rows and soon falling; stamens numerous, yellow. Fruit a narrow, one-celled, two-valved capsule, pointed at both ends, about 1 inch long.
In rich woods and on shaded banks, Nova Scotia to Manitoba and Nebraska, south to Florida, Alabama and Arkansas. Flowering in April and May.
Memoir 15 N. Y. State Museum
Plate 77 bloodroot; puccoon-root

Sanguinaria canadensis
 
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