White Vervain

Description:

This wildflower is an annual, biennial, or short-lived perennial about 3-6' tall; it branches occasionally in the upper half. The central stem is light green, stout, 4-angled, and densely covered with long spreading hairs. Along its length are pairs of opposite leaves up to 6" long and 2¼" across; they are lanceolate to ovate and coarsely serrated along their margins. The upper surface of each leaf is medium to dark green, shiny, hairless to slightly hairy, and wrinkled along the veins; its lower surface is light green and more hairy. The petioles of the leaves are up to 2" long. The central stem terminates in a panicle of floral spikes up to 2' long and half as much across; the upper side stems also terminate in such panicles, although they are smaller in size. Each panicle has narrow ascending branches (up to 6" long) and an airy appearance; sessile small flowers are sparsely distributed along each of these branches. Each flower is 1/8" (3 mm.) across, consisting of a white corolla with 5 rounded lobes and a tubular green calyx with 5 lanceolate teeth. The blooming period occurs from mid-summer to early fall and lasts about 1½ months. Only a few flowers bloom at the same time. Each flower is replaced by 4 nutlets that are oblongoid and flattened. This wildflower reproduces by reseeding itself.