互花米草 hu hua mi cao

Spartina glabra Muhlenberg ex Elliott var. alterniflora (Loiseleur) Merrill; S. maritima (Curtis) Fernald var. alterni-flora (Loiseleur) St.-Yves; S. stricta Roth var. alterniflora (Loiseleur) A. Gray; Trachynotia alterniflora (Loiseleur) Candolle.

Perennial with soft fleshy rhizomes. Culms stout, forming large clumps, erect, (0.5–)1–2(–3) m tall, ca. 1 cm in diam. Leaf sheaths mostly longer than internodes, smooth; leaf blades linear-lanceolate, flat, 10–90 × 1–2 cm, smooth or margins minutely scabrous, tapering to long hard involute apex; ligule ca. 1 mm. Racemes racemosely arranged, (5–)10–20, 5–20 cm, slender, erect or slightly spreading; spikelets scarcely overlapping; rachis smooth, terminating in a bristle up to 3 cm. Spikelets ca. 10 mm, glabrous or nearly so; lower glume linear, 1/2–2/3 as long as spikelet, acute; upper glume ovate-lanceolate, as long as spikelet, glabrous or with very short hairs on keel, subacute; lemma lanceolate-oblong to narrowly ovate, glabrous; palea slightly longer than lemma. Anthers 5–6 mm. 2n = 62.

Tidal mudflats of coast, introduced. Fujian, Guangdong, Guangxi, Hebei, Jiangsu, Shandong, Zhejiang [native to Atlantic coast of North America].

Spartina alterniflora was first introduced to China from North America in 1979. From eight initial plantings in 1985 it has spread rapidly in suitable habitats along the whole Chinese coast. It is used to protect coastal dykes from tidal erosion and to promote sediment build-up for polder formation. Plantations are also used for pasture and cut for green manure and forage.