Mimosa pigra
Distribution: Native to the tropical Americas. Today, it has been widely and rapidly naturalized in tropical areas. This plant was introduced to Taiwan and has become naturalized. It grows in central and southern areas and has a tendency to spread.
Morphology: Upright, multi-branched shrub. The stems have sharp recurved thorns and are covered in hairs. The leaves are bipinnately compound, alternate, with 5-15 pairs of pinnae; 18-54 pairs of leaflets, linear to oblong, 3-12.5 mm long, with 3-5 parallel veins, bristly edges, and rachises covered in thorns. The flowers are purplish red to light red, with 1-3 capitula, terminal or in higher leaf axils, arranged in racemes; eight stamens. One flower forms 4-6 pods. The pods are linear to oblong, 4-8 cm, flat, densely covered in long, hard thorns that are not sharp. The seeds are ellipsoid to oblanceolate, 5-7 mm in length.
Uses: Ornamental. The indigenous peoples of the West Indies use it as medicine. It is listed among the 100 World’s Worst Invasive Alien Species and damages the ecology and reduces crop production.
