Northern Prairie Wildlife Research Center
Appearance of the small, but striking, white milkwort signals the end of May on the Dakota prairies. White milkwort does not occur in extreme northeastern North Dakota, but can he found from Washington and the Prairie Provinces southward to Mexico.
White milkwort stands six to ten inches tall. Up to two dozen slender stems curve upward and outward from the top of the slender taproot. Leaves are less than an inch long and very narrow. Up to four dozen tiny creamy-white flowers are densely crowded on the tips of the stems.
This plant usually is found in greater abundance where grazing is moderate to heavy. Many of the 500 or so species of Polygala found worldwide are used for food, fiber, drug, dye, or perfume purposes, but white milkwort seems to have no known economic value.
White milkwort is a member of the milkwort family (Polygalaceae). The family and genus name stem from the Greek polus, "much," and gala, "milk." Thus the ancient Greek physician to the Roman Army, Dioscorides, applied the name Polygala to some low shrub reputed to increase lactation. The specific epithet alba means "white" in Latin. White milkwort was described for science in 1818 by the great English botanist Thomas Nuttall, who worked at Fort Lisa in what now is Mercer County, North Dakota, in 1811.