Japanese Zoysiagrass

This is a very good lawn grass, and it may be found as an escape.

This species can be distinguished by its relatively short, broad leaf blades, broadly linear inflorescence well exserted above the leaves, and many short, plump spikelets on long, slender pedicels.

This species is a good lawn grass.

Culm slender, tufted, with long creeping stolon. Blade linear, needle-like, 2-3 mm long by 1-2 mm wide; sheath-mouth densely covered with long silky hairs; ligule about 0.2 mm long, upper part a fringe of hairs, backside ciliate. Inflorescence a terminal single raceme, about 2 cm long. Spikelets 1-flowered, 2-3 mm long; upper glume coriaceous, 5-7-nerved, ovate, bilaterally compressed, margins membranous, slightly inrolled, as long as the spikelet, minutely hispid on backside; lemma lanceolate, boat-shaped, 1-nerved, membranous, about 2 mm long. Both palea and lodicules reduced.

Perennial, with long slender stolons, forming large mats. Culms erect, up to 20 cm tall, sometimes branched at base. Leaf sheaths glabrous, pilose at mouth with 1–2 mm hairs, basal sheaths persistent; leaf blades aggregated toward culm base, linear-lanceolate, flat or margins involute, tough, patent, 2.5–6 cm, 2–4 mm wide, abaxial surface subglabrous, adaxial surface thinly pilose, apex pungent. Inflorescence linear-elliptic, 2–4 × 0.3–0.5 cm, long exserted above leaves; spikelets many, loosely overlapping; pedicels slender, slightly flexuous, longer than spikelet, up to 5 mm. Spikelets 2.5–3.5 × 1–1.5 mm, yellowish green becoming purplish brown; lower glume absent; upper glume obliquely ovate, obscurely 5–7-veined, upper margins broad, papery, apex obtuse, sometimes mucronate; lemma boat-shaped, slightly shorter than glume, 1-veined; palea absent. Anthers ca. 1.5 mm. Caryopsis 1.5–2 mm. Fl. and fr. May–Aug. 2n = 40.

Coastal areas, grassy hillsides, open places. Hebei, Hong Kong, Jiangsu, Jiangxi, Liaoning, Shandong, Taiwan, Zhejiang [Japan, Korea].

Zoysia matrella (L.) Merr. var. japonica (Steud.) Sasaki, List Pl. Form. 80. 1928; Masamune & Yanagihara in Trans. Nat. Hist. Soc. Form. 31: 327. 1941.

Zoysia koreana Mez; Z. matrella (Linnaeus) Merrill subsp. japonica (Steudel) Masamune & Yanagita; Z. matrella var. japonica (Steudel) Sasaki; Z. pungens Willdenow var. japonica (Steudel) Hackel.