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.

Semiarundinaria yashadake

HABIT Perennial. Rhizomes elongated; leptomorph. Culms erect; 700–800 cm long; 30–40 mm diam.; woody. Culm-internodes terete; hollow; 3–5 cm long; mid-green, or purple. Lateral branches dendroid. Branch complement three, or several; in a horizontal line. Culm-sheaths coriaceous; pilose; with dark brown hairs; without auricles; setose on shoulders. Culm-sheath ligule 1.5 mm high; ciliolate. Culm-sheath blade linear, or lanceolate; acuminate. Leaves cauline; 3–5 per branch. Leaf-sheath oral hairs setose. Ligule a ciliolate membrane. Leaf-blade base with a brief petiole-like connection to sheath. Leaf-blades lanceolate, or elliptic. Leaf-blade surface glabrous. Leaf-blade apex acuminate.

INFLORESCENCE Synflorescence bractiferous; fasciculate; with spathaceous subtending bracts; bracts 20–25 mm long; without axillary buds at base of spikelet; with ultimate bract subtending a compact bracteolate fascicle of spikelets; prophyllate below lateral spikelets.

Fertile spikelets sessile.

FERTILE SPIKELETS Spikelets comprising 3–4 fertile florets; with diminished florets at the apex. Spikelets lanceolate; laterally compressed; 30–40 mm long; breaking up at maturity; disarticulating below each fertile floret. Rhachilla internodes 5 mm long; glabrous.

GLUMES Glumes one the lower absent or obscure; persistent; shorter than spikelet. Upper glume ovate; 5–7 mm long; chartaceous; without keels. Upper glume apex acute.

FLORETS Fertile lemma oblong; 15 mm long; chartaceous; without keel; 13 -veined. Lemma lateral veins with cross-veins. Lemma apex acute. Palea 14 mm long; coriaceous; 7 -veined. Palea keels ciliolate; adorned above. Palea apex with excurrent keel veins. Apical sterile florets resembling fertile though underdeveloped.

FLOWER Lodicules 3; ovate; 3 mm long; veined; ciliate. Anthers 3; 7 mm long. Stigmas 3.

FRUIT Caryopsis with adherent pericarp.

DISTRIBUTION Asia-temperate: eastern Asia.

NOTES Arundinarieae. Index Jap. Bam. 2001.

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