Herbs, annual [slightly woody at base]; taproot tapered, soft or ± woody. Stems usually erect, sometimes decumbent, profusely branched primarily distally, 2-12 dm, minutely puberulent with bent hairs basally, usually glabrous, rarely sparsely puberulent distally. Leaves mostly in basal 1/2 of plant; larger leaves with petiole 6-40(-55) mm, blade broadly rhombic-ovate, triangular-ovate, ovate, oval, or lanceolate, 20-50(-80) × 10-45 mm (distal leaves smaller, proportionately narrower), adaxial surface usually glabrous, sometimes minutely puberulent, usually minutely punctate, abaxial surface slightly paler than adaxial, usually glabrous, sometimes minutely puberulent, usually punctate with small patches of small brown cells, base obtuse to round, margins entire or sinuate, apex usually acute, less often obtuse or rounded. Inflorescences terminal, forked ca. 4-6 times ± evenly, diffuse, usually with sticky internodal bands; branches strongly ascending, terminating in irregular umbellate or subracemose clusters of flowers, not all pedicels attaching at same point (flowers occasionally borne singly). Flowers: pedicel (0-)0.3-2.5(-5) mm; bracts at base of perianth deciduous, usually 2, narrowly to broadly lanceolate, 0.5-1 mm, apex often acuminate; perianth whitish, usually tinged with pink or purple [bright pink] between lobes and in tube, campanulate beyond constriction, 1-1.5 mm; stamens 2-4, slightly exserted. Fruits 1-11 per cluster, pale greenish to straw colored or tan, narrowly obconic, (2.7-)3-3.5[-4] × 1.2-1.5 mm (l/w: (2-)2.3-3.2), apex truncate or broadly low conic, glabrous; ribs 5, acute, slightly rugose adjacent to sulci; sulci 0.5-1 times as wide as base of ribs, slightly to prominently coarsely transverse rugose, not papillate. Flowering early summer-mid fall. Disturbed areas, gardens, road and railroad rights-of-way, stream beds; 0-1700 m [probably much higher in tropics]; Ala., Ariz., Ark., Fla., Ga., La., Md., Miss., Mo., N.Mex., N.C., Okla., S.C., Tenn., Tex.; Mexico; West Indies; Central America; South America; widely introduced throughout the tropics and warm-temperate regions. Boerhavia erecta occasionally forms mixed populations with B. intermedia without apparent intergradation. Rarely, some specimens seem to combine features of either species, particularly with regard to inflorescence structure. This is especially so in Sonora, Mexico, and in parts of the Sonoran Desert in Arizona. The two species bloom simultaneously and are visited by small insects. Given the presumed close relationship and weedy habitats of each, hybridization seems possible. Usually, the two species can be distinguished by the differences in fruit length, the appearance of a crownlike apex of the nearly mature fruits of B. erecta (apex of ridges slightly expanded, apex of fruit slightly conic), and the more precisely constructed terminal umbels of B. intermedia. Both species, particularly B. intermedia, may produce entire inflorescences with branches terminating in single flowers. R. E. Woodson Jr. and H. J. Kidd (1961) suggested that B. erecta hybridizes with the perennial B. diffusa.
Wiggins 1964, FNA 2003, Kearney and Peebles 1969
Duration: Annual Nativity: Native Lifeform: Forb/Herb General: Usually coarse, glaucous annuals 30-100 cm, glabrous or hirsutulous below, branching from base and above, branches ascending, basal branches sometimes procumbent. Leaves: Opposite, ovate to oblong-ovate, usually acute, rarely rounded at apex, entire or subsinuate, glabrous, lower leaves 2.5-8 cm long, upper ones short, narrowly ovate-lanceolate; sometimes with moderately to densely glandular patches. Flowers: Cymosely paniculate, much branched, branches and branchlets erect or strictly ascending; flowers umbellate, or subracemose in clusters of 3-6 flowers, occasionally in twos or solitary on older inflorescences, perianth greenish or white, sometimes tinged with pink, 1 mm or longer; stamens 2-3, subtending bracts minute, deciduous. Fruits: Anthocarp greenish or brownish green, 5 angled, 3-4.5 mm long, narrowly obpyramidal, strongly narrowed below, ridges smooth. Ecology: Found in open places and disturbed areas from 1,000-5,000 ft (305-1524 m); flowers July-August. Distribution: From AZ east to NC south to FL ; south to S. Amer.; also in Africa Polynesia and Australia. Notes: Distinguished by being an annual with pink flowers in non-glandular cymes (as opposed to racemes in torreyana) which appear to be umbels (upon closer inspection the branches don-t come from the same point) with unequal pedicels. Widely distributed in the topics, can be very erect and stand up to 1 m easily, often distinctive with the slight reddish outline of the leaf margins and the mis-matched leaf size. Ethnobotany: The Hopi would take the stem and leaves and hang them upside down in the house as a fly-trap. Etymology: Boerhavia is for Hermann Boerhaave (1663-1738) a Dutch botanist, erecta means upright. Synonyms: None Editor: SBuckley 2010, FSCoburn 2015