GrassBase - The Online World Grass Flora

Descriptions

W.D. Clayton, M. Vorontsova, K.T. Harman & H. Williamson

© Copyright The Board of Trustees, Royal Botanic Gardens, Kew.

Pleioblastus amarus

HABIT Perennial. Rhizomes elongated; leptomorph. Culms erect; 100–400 cm long; 15 mm diam.; woody. Culm-internodes terete; hollow; 10–25 cm long; distally pruinose. Lateral branches dendroid. Leaves cauline; 3–4 per branch. Leaf-sheaths 3.5–7 cm long; glabrous on surface. Leaf-sheath oral hairs lacking. Ligule an eciliate membrane; 1–2 mm long; truncate. Leaf-blade base with a brief petiole-like connection to sheath; petiole 0.2–0.7 cm long. Leaf-blades lanceolate; 8–16 cm long; 10–28 mm wide. Leaf-blade venation with 8–16 secondary veins; with distinct cross veins. Leaf-blade margins scabrous. Leaf-blade apex acuminate.

INFLORESCENCE Synflorescence compound; fasciculate. Inflorescence composed of racemes; terminal and axillary; embraced at base by subtending leaf.

Racemes 1; single; bearing 3–10 fertile spikelets on each.

Spikelets solitary. Fertile spikelets pedicelled. Pedicels straight, or flexuous; 3–12 mm long; puberulous; hairy on margins.

FERTILE SPIKELETS Spikelets comprising 8–12 fertile florets; with diminished florets at the apex. Spikelets linear; laterally compressed; 40–60 mm long; breaking up at maturity; disarticulating below each fertile floret. Rhachilla internodes thickened; 4–5 mm long; pubescent; hairy above.

GLUMES Glumes several; 3–5 empty glumes; persistent; similar; shorter than spikelet. Lower glume lanceolate; 20–45 mm long; chartaceous; without keels. Lower glume primary vein eciliate, or pubescent.

FLORETS Fertile lemma lanceolate, or ovate; 8–11 mm long; chartaceous; without keel; 9–11 -veined. Lemma lateral veins with cross-veins. Lemma margins eciliate, or ciliolate; hairy above. Lemma apex acute; muticous, or mucronate. Palea 1 length of lemma; 2 -veined. Palea surface pubescent; hairy on back. Palea apex obtuse. Apical sterile florets resembling fertile though underdeveloped.

FLOWER Lodicules 3; ovate; 4 mm long; veined; ciliate. Anthers 3; 5–6 mm long; yellow. Stigmas 3.

FRUIT Caryopsis with adherent pericarp; apex unappendaged.

DISTRIBUTION Asia-temperate: China.

NOTES Arundinarieae. Keng 1996.

Please cite this publication as detailed in How to Cite Version: 3rd February 2016.