3. Gleditsia fera (Loureiro) Merrill, Philipp. J. Sci., C. 13: 141. 1918.
华南皂荚 hua nan zao jia
Mimosa fera Loureiro, Fl. Cochinch. 2: 652. 1790; Gleditsia formosana Hayata; G. thorelii Gagnepain.
Trees, 3-24 m tall. Branches grayish brown. Spines robust, branched, terete at base, to 13 cm. Leaves pinnate, 11-18 cm; rachis sulcate, glabrous or pilose; petiolules ca. 1 mm; leaflets 5-9 pairs, adaxially deep brown, shiny, obliquely elliptic to rhombic-oblong, 2-7(-12) × 1-3(-5) cm, papery to thinly leathery, abaxially glabrous, adaxially glabrous or sometimes pubescent on midvein, midvein inclined to one side at base of blade, reticulate veinlets crowded, slender, conspicuously raised, base obliquely cuneate or rounded and oblique, margin crenate, sometimes shallowly, obtusely serrate, apex rounded and emarginate. Flowers several in cymules, polygamous, greenish white, cymules in axillary or terminal racemes 7-16 cm. Male flowers: 6-7 mm in diam.; receptacle ca. 2.5 mm; sepals 5, triangular-lanceolate, 2.5-3 mm, outside densely puberulent; petals 5, oblong, both sides puberulent; stamens 10; rudimentary pistil linear-terete, 4-5 mm, villous. Bisexual flowers: 8-10 mm in diam.; calyx and petals similar to those of male flowers, but calyx with a villous ring inside at base; stamens 5 or 6; anthers acute at apex; ovary densely brownish yellow silky, many ovuled. Legume compressed, 13.5-26(-41) × 2.5-3(-6.5) cm, straight or slightly curved, occasionally twisted, valves leathery, densely brownish yellow puberulent when young, glabrescent and becoming deep brown to blackish brown when old, apex with beak 2-5 mm; stipe 5-10 mm. Seeds numerous, brown to blackish brown, compressed or lenticular, ovoid to oblong, 8-11(-14) × 5-6(-11) mm, smooth. Fl. Apr-May, fr. Jun-Dec.
● Gentle slopes, mountain valleys, forests, beside villages, near roads, sunny places, occasionally cultivated; 300-1000 m. Fujian, Guangdong, Guangxi, ?Guizhou, ?Hainan, Hunan, Jiangxi, Taiwan, ?Yunnan.
The records of Gleditsia rolfei S. Vidal from Taiwan (Fl. Taiwan 3: 293. 1977; ed. 2, 3: 182. 1993) are referable to G. fera.
The fruit contains saponin that can be used as soap and as an insecticide.