Verbena bracteata Lag. & Rodr.
Family - Verbenaceae
Stems - Prostrate to decumbent, hirsute, herbaceous, multiple from base, to 50cm long, +/-20cm tall, 4-angled, branching.
Stem and node.
Leaves - Opposite, petiolate, typically 3-lobed, hirsute, to +6cm long, +4cm broad. Petioles winged, short. Lobes typically of 2 lateral and one larger terminal, often divided again, serrate-dentate.
Inflorescence - Terminal bracteate spikes to 15cm long (tall), elongating in fruit. Flowers subtended by lance-oblong bracts. Bracts to +/-2cm long, 4mm broad, hirsute. Axis (stem) hirsute. Inflorescence diameter typically 1-2 cm.
Flowers - Corolla blue-purple, 5-lobed, salverform, zygomorphic, to 7mm long, 3mm broad at apex, sparsely pubescent externally, pubescent internally. Lobes obtuse at apex. Stamens 4, didynamous, adnate near base of corolla tube, included. Filaments short. Anthers yellow, .2mm long. Style short. Ovary of 2 carpels, 4-lobed. Calyx hirsute, 5-lobed. Tube to 3.5mm long. Lobes linear.
Fruits - Nutlets 4, oblong, 2.0-2.5 mm long, enclosed within persistent calyx.
Flowering - April - October.
Habitat - Disturbed sites, waste ground, pastures, roadsides, railroads.
Origin - Native to U.S.
Other info. - Fortunately,
not much close dissection is needed to properly identify this species.
The flower parts are very small but the plant can be easily identified
by looking at the hirsute stems, flower spikes, and leaves, as well as
the tiny flowers. This is somewhat of a pioneering species that is out-competed
by larger plants.
Photographs taken in St. Louis, MO., 7-28-03 and 8-15-03 (DETenaglia); also in Washington, Franklin County, MO, 7-15-2018 (SRTurner).