Time of bloom: July to September.
Seed-time: August to October.
Range: Quebec and Ontario to Minnesota, southward to Georgia, Mississippi, Arkansas, and Nebraska.
The winter rosettes and deep-boring taproot of this plant resemble those of the Evening Primrose, to which it is a near relative. Flowering-stalks, which appear in the second year, are two to five feet tall, erect, much branched, and covered with finely downy hairs, hard and woody when mature, and very troublesome to harvesting machinery. Leaves alternate, lance-shaped, pointed at both ends, sparsely toothed or wavy-edged, smooth above but finely hairy beneath, sessile, two to four inches long. Flowers sessile on slender terminal spikes, the succession of bloom beginning at the base of the spike with hairy buds above; each blossom is nearly a half-inch across, with four cream-white petals, turning pink as they wither, four long-pointed, reflexed calyx-lobes, usually eight stamens, drooping like a tassel, and a long, declining style with four-parted stigma; ovary at the base of the long calyx-tube, one-celled. Fruits nut-like, four-ribbed, pointed at both ends, finely downy, and nearly a half-inch long. (Fig. 207.)
Fig. 207. - Biennial Gaura (Gaura biennis). X 1/4.
Leaf-tufts of autumn plants should be spudded off or destroyed by deep hoe-cutting. Plants that have survived to the second season should have flowering-stalks closely cut in their first bloom, the shorn surfaces being treated with salt in order to prevent stool-ing. If not allowed to mature seed the weed is readily suppressed.