This section is from the book "An Illustrated Flora Of The Northern United States, Canada And The British Possessions Vol3", by Nathaniel Lord Britton, Addison Brown. Also available from Amazon: An Illustrated Flora of the Northern United States, Canada and the British Possessions. 3 Volume Set..
Verbena urticifolia L. Sp. Pl. 20. 1753.
1894. V. riparia Raf.; Small & Heller, Mem. Torr. Club 3: 12.
Perennial, usually pubescent; stem slender, strict, erect, 4-sided, paniculately branched above, 3°-5° high, the branches upright. Leaves ovate, oblong, or oblong-lanceolate, all petioled, or the uppermost sessile, serrate-dentate all around, or incised, sometimes 3-cle.ft near the base, thin, acute or acuminate, mostly rounded at the base, 1 1/2' - 5' long; spikes numerous, filiform, erect, or spreading, at length 4'-6' long; fruits oblong, scattered, not at all imbricated, about 1" high; bracts ovate, acuminate, shorter than the calyx; corolla white, blue or pale purple, its limb about 1" broad.
In fields and waste places, New Brunswick to South Dakota, Kansas, Florida and Texas. Hybridizes with V. bracteosa, V. hastata and V. stricta. June-Sept.
Verbena hastata L. Sp. Pl. 20. 1753. Verbena pinnatifida Lam. Tabl. Encycl. 1: 57. 1791. Verbena paniculata Lam. Encycl. 8: 548. 1808. Verbena hastata pinnatifida Britton, Mem. Torr. Club 5: 276. 1894.
Perennial, roughish-puberulent; stem erect, strict, 4-sided, usually branched above, 3°-7° high. Leaves oblong-lanceolate or lanceolate, petioled, acute or acuminate at the apex, narrowed at the base, serrate or incised-dentate with acute teeth, sometimes pinnatifid, 3-6' long, the lower sometimes hastately 3- lobed at the base; spikes numerous, panicled, slender, usually peduncled, 2'-6' long; fruits densely imbricated on the spikes, 1"- 1 1/2" high; bracts ovate, acuminate, shorter than the calyx; corolla blue, white, or sometimes pink, its limb about 1 1/2" broad.
In moist fields, meadows and in waste places, Nova Scotia to British Columbia, Florida, Nebraska and Arizona. Hybridizes with V. stricta and V. bracteosa. American vervain. Purvain. Iron-weed. June-Sept.
V. angustifolia Michx. Fl. Bor. Am. 2: 14. 1803.
Perennial, roughish-puberulent or pubescent; stem slender, simple or branched, 4-sided above, 1°-2° high. Leaves linear, spatulate or lanceolate, obtuse or subacute at the apex, cuneate at the base and tapering into short petioles, serrate or serrulate, veiny, 1 1/2'- 3' long, 2"-s" wide; spikes mostly solitary at the ends of the branches, usually peduncled, slender, dense, 2'-5' long; fruits overlapping or the lower somewhat distant, 1 1/2" high; bracts lanceolate, acuminate, equalling or shorter than the calyx; corolla purple or blue, about 3" long, its limb about as broad, the lobes obovate or oblong.
In dry fields, Massachusetts to Florida, west to Minnesota, Kansas and Arkansas. Hybridizes with V. stricta and V. bracteosa. June-Aug.