Verbena simplex Lehm.

Narrow-Leaved Vervain

© DETenaglia

Family - Verbenaceae

Habit - Perennial forb.

Stems - Erect, to 70 cm, 4-angled, multiple from the base, branching, sparsely to moderately pubescent with nonglandular, straight, strongly ascending, occasionally pustular-based hairs.

	Stem and leaves.
© SRTurner

	Stem and node.
© SRTurner

Leaves - Opposite, sessile or with a winged petiole, the blades 2-8 cm long, 1-10 mm wide, narrowly lanceolate to oblanceolate or linear, tapered to a slender, nonclasping base, mostly angled to a bluntly or sharply pointed tip, unlobed, the margins relatively finely toothed, both surfaces sparsely pubescent with appressed, nonglandular, occasionally pustular-based hairs, especially along the veins, the upper surface sometimes nearly glabrous.

	Leaf adaxial.
© SRTurner

	Leaf abaxial.
© SRTurner

	Pressed leaves.
© DETenaglia

Inflorescence - Solitary terminal spikes, 4-25 cm long, 5-8 mm in diameter, moderately dense (the flowers strongly overlapping except sometimes the lowermost ones), slender, elongating greatly with age. Flowers each subtended by a single bract, this 3-5 mm long, equaling or shorter than calyx tube, lanceolate, ciliate-margined, otherwise glabrous.

	Inflorescence.
© SRTurner

	Inflorescence.
© SRTurner

Flowers - Calyces 3-4 mm long. Corollas zygomorphic, 5-lobed, 4-6 mm long, the outer surface sparsely hairy toward the tip of the tube, funnelform to somewhat trumpet-shaped, dark lavender or purple to white or bluish-tinged, the tube relatively slender, the limb 4-6 mm in diameter. Stamens 5, didynamous, included, adnate around middle of corolla tube. Style included, 2-lobed. Ovary of 2 carpels, 4-lobed.

	Flowers.
© SRTurner

Fruits - Nutlets 2-3 mm long, narrowly oblong to narrowly oblong-elliptic in outline, the inner surface usually slightly pale and smooth or with sparse to moderate, minute papillae, the outer surface greenish brown to reddish brown, with several longitudinal ridges, these with several cross-ridges above the midpoint.

	Immature fruits.
© SRTurner

Flowering - May - September.

Habitat - Glades, tops of bluffs, upland prairies, streambanks, pastures, fields, railroads, roadsides, open disturbed areas.

Origin - Native to the U.S.

Lookalikes - Other species of Verbena, particularly V. stricta.

Other info. - This species is found throughout most of Missouri and, in somewhat scattered fashion, across much of the eastern half of the continental U.S. This small plant can be recognized by its tall thin flower spikes and its narrow serrate leaves. It is tolerant of fairly poor soils and can sometimes be found growing in gravelly areas. The flower color is variable, ranging from white to bluish or lavender. This species has the narrowest leaves of any of Missouri's Verbena species. Like most members of the genus, it hybridizes readily.

Photographs taken somewhere in NC., 5-16-03 (DETenaglia); also at Shaw Nature Reserve, Franklin County, MO, 6-30-2008, near Gray Summit, Franklin County, MO, 6-1-2013, and Gist Ranch Conservation Area, Texas County, MO, 6-9-2022 (SRTurner).