10. Oligostachyum lubricum (T. H. Wen) P. C. Keng, J. Nanjing Univ., Nat. Sci. Ed. 22(3): 415. 1986.
四季竹 si ji zhu
Semiarundinaria lubrica T. H. Wen, J. Bamboo Res. 2(1): 64. 1983; Arundinaria lubrica (T. H. Wen) C. S. Chao & G. Y. Yang.
Culms ca. 5 m, ca. 2 cm in diam.; internodes green, ca. 30 cm, basally flattened above branches, without powder, glabrous. Culm sheaths green, sparsely white or yellow hairy or with imprints and brown papillae from fallen hairs, margins white ciliate; auricles purple or brown, ovate or rarely falcate; oral setae erect, flexuose; ligule purple, truncate, ca. 1.5 mm, margin purple ciliate; blade green, broadly lanceolate, margins ciliate, base contracted, apex acuminate. Leaves 3 or 4 per ultimate branch; sheath pubescent; auricles purple; oral setae usually developed; ligule purple, arcuate or truncate; blade linear-lanceolate, 10–15 × 1.5–2.5 cm, both surfaces glabrous or abaxially scabrous, secondary veins 6-paired, transverse veins distinct. Racemes with 1–4 spikelets; peduncle and branches partially exserted from sheathlike bracts with small blades; axes glabrous. Spikelets to 6 cm, compressed; florets 4–9, lowest one sterile with a lemma enclosing a very small palea. Glumes 1 or 2, 1st 5–8 mm, inconspicuously 5–9-veined, apex and midvein puberulent, 2nd longer, 7–11-veined; lemma purple-red, 1.6–1.8 cm, abaxially initially scabrid and pubescent, adaxially distally puberulent, 11–13-veined; palea keels long ciliate, apex obtuse or emarginate, 5-veined between keels, each flank 4-veined; lodicules 3, upper part membranous, margins ciliate. Stamens 3; anthers yellow, ca. 4 mm. Stigmas 2. New shoots May–Oct, fl. May.
* 400–500 m. Fujian, Jiangxi, Zhejiang.