Vachellia tortuosa

Shrubs or trees, erect, to 6 m; bark dark gray to dark brown, shallowly furrowed. Stems strongly flexuous, usually pubescent, not glutinous; short shoots present. Leaves 12–45 mm; stipular spines terete, straight, 5–40(–55) × 0.7–1.5 mm near base; petiole 3–7 mm, usually densely pubescent, hairs erect; petiolar gland 1, variable between medial to near basal positions of lowermost pinnae, sessile, elongated to circular, 0.3–2 mm, apex depressed; rachis 5–40 mm; pinnae 2–8 pairs, 12–23 mm; leaflets 11–19 pairs per pinna, blades flat, oblong, 3–5.5 × 0.9–1.5 mm, base oblique and obtuse, apex broadly acute to obtuse, surfaces glabrous. Peduncles 12–36 mm. Inflorescences globose heads, densely flowered, 6–9 mm diam., solitary or clusters of 2–5 on short shoots; involucre at base of head (not obvious). Flowers pale yellow; calyx 1.1–1.8 mm, pubescent; corolla 1.5–2.4 mm, pubescent; filaments yellow, 3.5–4.5 mm. Legumes linear, elliptic in cross section, 65–150 × 5–9 mm, constricted between seeds. Seeds uniseriate. 2n = 26.

Phenology: Flowering year-round.
Habitat: Thickets, open pastures, successional fields, dry sites.
Elevation: 0–10 m.

Introduced; Fla., West Indies, Central America (Panama), South America.

Discussion

Vachellia tortuosa is a lowland species, occurring at or near sea level in southern Florida and the West Indies where it is the dominant and co-dominant of the woody vegetation in scrub thickets. Its presence in extreme southern Florida (Collier, Miami-Dade, and Monroe counties) was probably the result of pre-Columbian introduction, as this species was always associated with sites of human occupation. It is not known from Mexico or most of Central America (H. D. Clarke et al. 1989).

Selected References

None.

Lower Taxa