Description from Flora of China
Gleditsia horrida Willdenow; G. macracantha Desfontaines; G. officinalis Hemsley.
Trees or small trees, to 30 m tall. Branches grayish to deep brown. Spines robust, terete, conical, to 16 cm, often branched. Leaves pinnate, 10-18(-26) cm; petiolules 1-2(-5) mm, puberulent; leaflets (2 or)3-9 pairs, ovate-lanceolate to oblong, 2-8.5(-12.5) × 1-4(-6) cm, papery, abaxially slightly pubescent on midvein, adaxially puberulent, reticulate veinlets conspicuously raised on both surfaces, base rounded or cuneate, sometimes slightly oblique, margin serrate, apex acute or acuminate, tip rounded, mucronate. Flowers polygamous, yellowish white, in axillary or terminal, puberulent racemes 5-14 cm. Male flowers: 9-10 mm in diam.; pedicels 2-8(-10) mm; receptacle deep brown, 2.5-3 mm, outside pubescent; sepals 4, triangular-lanceolate, ca. 3 mm, both sides pubescent; petals 4, oblong, 4-5 mm, puberulent; stamens (6-)8; rudimentary pistil ca. 2.5 mm. Bisexual flowers: 10-12 mm in diam.; pedicels 2-5 mm; sepals and petals similar to those of male flowers but longer; stamens 8; ovary hairy at base and on sutures; ovules numerous; stigma 2-lobed. Legume brown or reddish brown, curved, strap-shaped, 12-37 × 2-4 cm, straight or twisted, with slightly thick pulp, swollen on both surfaces, some legumes shorter and smaller, ± terete, 5-13 × 1-1.5 cm, without seeds; stipe 1-3.5 cm; valves leathery, often farinose. Seeds numerous, brown, shiny, oblong or elliptic, 11-13 × 8-9 mm. Fl. Mar-May, fr. May-Dec. 2n = 28*.
Specimens from Sichuan called "zhu ya zao," named as Gleditsia officinalis, with curved, small fruit without seeds, are an abnormal type and are referable to this species.
● Mountain slopes, forests, valleys, near roads; 200-2500 m. Anhui, Fujian, Gansu, Guangdong, Guangxi, Guizhou, Hebei, Henan, Hubei, Hunan, Jiangsu, Jiangxi, ?Qinghai, Shaanxi, Shanxi, Sichuan, Yunnan, Zhejiang.