Flower:

Flowers arise in dense, cylindrical spike-like racemes at the top of the plant and the tips of branching stems. Flowers are flanked by a pair of triangular petal-like sepals, each up to ¼ inch (4 to 6 mm) long, nearly as wide, sharply pointed at the tip. Three small petals are fused into a short column in the center, fringed with short, finger-like lobes at the tip. Color ranges from greenish-white to deep pink. Flower clusters are about ½ to ¾ inch (to 2 cm) in diameter and can elongate up to about 2 inches during the growing season, with flowers blooming at the tip and fruit forming below.

Leaves and stem:

Leaves are typically whorled in groups of 4, sometimes 3, up to 1½ inches (1 to 4 cm) long, linear to narrowly elliptic or spatula-shaped, widest at or above the middle, blunt to pointed at the tip, toothless, hairless, and stalkless or nearly so. Stems are square or slightly winged, hairless, stiff and branched, the branches often in pairs at a leaf node.

Fruit:

Fruit is a nearly round, 2-seeded capsule up to 2.5 mm long on a stalk-like base. Seeds are oval-elliptic, 1.1 to 1.5 mm long, blackish-brown at maturity, short-hairy, with a 2-lobed appendage slightly shorter than the seed.

Notes:

Minnesota populations of Cross-leaved Milkwort are primarily restricted to sedge meadows of the Anoka Sandplain. It is a tiny thing, often hidden by the surrounding grass-like plants and easily stepped on if you aren't paying attention. According to the DNR, it was listed as an Endangered Species in 1984 due to loss of habitat to development and encroaching non-native invasive species threatening the dwindling populations that remain. Vaguely similar is Blood Milkwort (Polygala sanguinea), with which it often grows; it has alternate leaves and, after blooming, the flower sepals become erect and overlapping like fish scales.