Flora of the Southeastern United States

Spikes short and stout, the flowers or fruits overlapping and completely obscuring all of the rachis (except in V. montevidensis, the fruits spaced toward the base of the spike); [weedy exotics usually of disturbed areas]

Plant procumbent or decumbent; leaves pinnately lobed or dissected; [section Verbena, series Bracteatae]

Plant erect; leaves coarsely serrate.

Leaves basally attenuate to short-petiolate; corolla tubes 2.5-5 mm long.

Central spikes sessile to subsessile, spikes compact, 3-5 mm wide, fruits remaining densely overlapping at maturity; [section Verbenaca, series Pachystachyae]

Central spikes pedunculate, spikes loose, 2-3 mm wide, with fruits becoming remote at least in the proximal portion at maturity; [section Verbenaca, series Litorales]

Leaves basally clasping to subclasping; corolla tubes 2.5-9 (-11) mm long; [section Verbenaca, series Pachystachyae].

Corolla tube (5-) 6.5-9 (-11) mm long

Corolla tube 2.5-6 (-7) mm long.

Corolla tube 4-6 (-7) mm, 1.5-2 mm longer than the calyx; distal stems, peduncles, and calyces stipitate-glandular; spikes 8-30 mm long in fruit; floral bracts 2.1-2.8 mm; nutlets 1.5-1.9 mm; basal and midstem leaves oblong-lanceolate to oblong-oblanceolate

Corolla tube 2.5-4 mm, 0-0.5 mm longer than the calyx; stems, peduncles, and calyces eglandular; spikes (6-) 35-55 mm long in fruit; floral bracts 3-4 mm; nutlets 1-1.2 (-1.4) mm; basal and midstem leaves ovate to ovate-lanceolate, oblong-elliptic, or obovate

Spikes elongate, the flowers or fruits well-spaced and not obscuring the rachis; [exotics and natives, collectively of a range of habitats].

Leaves mostly lobed or dissected.

Plants much branched at base, stems decumbent to ascending; leaves 1-5 cm long; [section Verbena, series Tricesimae]

Plants little branched, stems erect; leaves 3-12 cm long.

Bractlets about as long as the calyx; [AL westward]; [section Verbena, series Candelabrae]

Bractlets about ½ as long as the calyx; [collectively widespread].

Basal and lower cauline leaves persistent, relatively thick, large and spatulate, margins revolute, cauline leaves quickly reduced in size distally and becoming linear-entire; rachis and calyces eglandular; [section Verbena, series Haleae]

Basal leaves usually deciduous, relatively thin, margins not revolute, cauline leaves relatively even-sized upward or largest near midstem; rachis and calyces stipitate-glandular, sometimes sparsely so; [section Verbena, series Verbena]

Leaves not lobed or dissected, or some of the leaves lower on the stem 3-lobed.

Stem leaves sessile or subsessile, cuneate to base.

Leaves linear to narrowly oblancolate, < 1.5 cm wide, > 6× as long as wide; [section Verbena, series Simplices]

Leaves ovate, 2-4 cm wide, < 4× as long as wide

Mericarps tightly adhering in fruit, appearing as one; calyx lobes curved inward in fruit; corolla pink to pinkish lavender; [section Verbena, series Connaticarpae]

Mericarps separate in fruit; calyx lobes erect to divergent in fruit; corolla blue to violet; [section Verbena, series Candelabrae]

Stem leaves with well-developed petioles.

Flowers and fruits distinctly overlapping in the upper part of the spikes; [section Verbena, series Candelabrae]

Flowers and fruits well-spaced throughout the inflorescence; [section Verbena, series Leptostachyae].

Upper leaf surfaces densely scabrous or hispidulous to hispid or hispid-hirsute; calyx lobes triangular, connivent; corollas mostly pinkish to bluish, lavender, or purple; nutlet outer surfaces deeply ridged and grooved, often with prominent cross-ridges, commisural faces consistently densely silver-white minutely papillate-bullate; fibrous-rooted

Upper leaf surfaces hirsutulous to hirsute or strigose-hirsute; calyx lobes deltate-subulate, not connivent or subconnivent; corollas white, rarely pinkish; nutlet outer surfaces smooth to longitudinally ridged, sometimes with cross-ridges distally, commisural faces smooth or rarely with slight development of minutely bullate ornamentation; taprooted