Annual herb 10 - 40 cm tall Stem: erect and branched. Leaves: in whorls of three to five, rarely opposite, with reduced or scale-like lower leaves. Middle and upper leaves are 1.5 - 3 cm long, 0.8 - 3 mm wide, and linear to linear-oblong with a pointed tip. Inflorescence: a dense cluster (raceme) on a 2 - 7 cm stalk, 0.6 - 1.5 cm long, to 7 mm across, narrow cylindrical to cone-shaped. Flowers: white to greenish or pinkish, with three small outer sepals and two petal-like inner sepals (wings) 4 - 5 mm long. The three petals are fused into a tube shorter than the wings, and one petal is fringed. Lower flowers drop as soon as the fruit begins to mature. Fruit: a dehiscent capsule, 1.5 mm long, oval, with finely hairy seeds. The seeds are attached to an appendage (aril) with two oblong to narrow egg-shaped lobes one-third to three-fourths the length of the seed.
Similar species: Polygala cruciata and Polygala verticillata have whorled leaves. Polygala cruciata has flower clusters that are larger than 7 mm across and leaves with a rounded to pointed tip. Polygala verticillata var. isocycla differs from the typical variety because it is shorter (5 - 20 cm tall), has only white to greenish flowers, and has inflorescence stalks shorter than 4 cm.
Flowering: late July to late August
Habitat and ecology: Dry and usually sandy soils, mostly south of the Chicago Region.
Occurence in the Chicago region: native
Etymology: Polygala comes from the Greek words polys, meaning much, and gala meaning milk, referring to the old belief that milkworts would aid in milk secretion. Verticillata means whorled.
Erect, divergently branched annual, 1-4 dm; lvs linear to linear-oblong, 1-2(-3) cm נ1-3 mm, at least the lower (sometimes all) in whorls of 2-5; lower branches of the infl usually opposite or whorled; peduncle elongate; racemes continuous, conic or cylindric- conic, the floriferous and fructiferous part 6-15 mm, appearing truncate at base, the whole axis to 4 cm; fls white, greenish, or occasionally pinkish, the lower dropping promptly as the fr matures; wings half to two-thirds as long as the fr; 2n=34. Moist, sandy soil, grasslands, and woods. July-Oct. Var. isocycla Fernald, occurring nearly throughout the range of the sp. (Vt. to Man., s. to Fla. and Tex.) has finely pubescent seeds, short pedicels a fourth to a third as long as the fr, greenish-white sep, narrow, dense racemes on peduncles 0.5-4 cm, the plant with widely spreading branches. Var. verticillata, occurring from Me. to Mich., s. to Tenn., has hirsute seeds, pedicels a third to half as long as the fr, often purplish sep, wider, looser racemes on peduncles 2-7 cm, and the branches are ascending.
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.
[Deam's treatment has three variations: vars. isocycla and sphenostachya in addition to var. verticillata. The common variety verticillata is a tall plant (2-3 dm) with hirsute seed, relatively long pedicels, and often purplish sepals. It grows] mostly near streams and lakes in dry sandy soil in black and white oak woods; rarely in the low sedge border of lakes. [Variety isocycla is a short plant (1-2 dm) with pubescent seed and small capsules (about 1 mm long). It grows] in poor soil in black and white oak woods and rarely in moist prairies. Rare. My only specimen [of var. sphenostachya, a medium height plant (1.5-3 dm) with pubescent seed and capsules ca. 1.5 mm long,] is from a sandy roadside cut four and a half miles north and a mile and a half west of Morocco, Newton County. Other specimens have been collected in Putnam, St. Joseph, and Tipton Counties.