Anthoxanthum japonicum

HABIT Perennial; caespitose; clumped loosely. Rhizomes short. Culms slender; 26–65 cm long; 1–1.2 mm diam.; 3–5 -noded. Culm-internodes distally glabrous. Lateral branches lacking. Leaf-sheaths longer than adjacent culm internode; glabrous on surface. Ligule an eciliate membrane; 2–6 mm long; truncate, or obtuse, or acute. Leaf-blades linear, or lanceolate; 12–20 cm long; 4–10 mm wide; aromatic. Leaf-blade surface smooth; pubescent; sparsely hairy; hairy adaxially.

INFLORESCENCE Inflorescence a panicle.

Panicle open, or contracted; ovate; loose; 5–10 cm long; 1–3.5 cm wide. Primary panicle branches 2 -nate; 1–3 cm long. Panicle branches smooth.

Spikelets solitary. Fertile spikelets pedicelled.

FERTILE SPIKELETS Spikelets comprising 2 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets elliptic, or oblong; laterally compressed; compressed slightly; 5–7 mm long; breaking up at maturity; disarticulating below each fertile floret. Rhachilla internodes elongated below proximal fertile floret. Rhachilla elongation 0.7–1 mm long.

GLUMES Glumes persistent; dissimilar; exceeding apex of florets; thinner than fertile lemma. Lower glume ovate; 3–4 mm long; 0.66 length of upper glume; membranous; 1-keeled; 1 -veined. Lower glume lateral veins absent. Lower glume apex acuminate. Upper glume lanceolate; 5–7 mm long; 2 length of adjacent fertile lemma; membranous; 1-keeled; 3 -veined. Upper glume apex acute.

FLORETS Basal sterile florets dissimilar; barren; without significant palea; attached to and deciduous with the fertile. Lemma of lower sterile floret oblong; 5–7 mm long; chartaceous; without keels; 5 -veined; pilose; dentate; 2 -fid; obtuse; mucronate. Awn of lower sterile floret dorsal; arising 0.5 way up back of lemma; 1.5–2 mm long. Lemma of upper sterile floret oblong; 5–7 mm long; chartaceous; pilose; dentate; 2 -fid; obtuse; awned. Awn of upper sterile floret dorsal; arising 0.25 way up back of lemma; geniculate; 4–5 mm long. Fertile lemma elliptic, or ovate; 2.5–3 mm long; cartilaginous; without keel; 5 -veined. Lemma lateral veins obscure. Lemma margins convolute; covering most of palea. Lemma apex emarginate. Palea oblong; 1 -veined; without keels.

FLOWER Lodicules absent. Anthers 2; 2–2.5 mm long. Stigmas 2; protogynous; pubescent.

FRUIT Caryopsis with adherent pericarp. Hilum punctiform.

DISTRIBUTION Asia-temperate: eastern Asia.

NOTES Aveneae. Koyama 1994.

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