久内早熟禾 jiu nei zao shu he

Annuals or short-lived perennials. Culms ascending to erect, 20–60 cm tall, nodes 3 or 4. Leaf sheaths shorter than internodes, smooth or scabrid; blade flat, grayish green, 4–8 cm × 1–3 mm, surfaces and margins scabrid; ligule 0.5–1.5 mm, abaxially pilulose, apex truncate to rounded, collar margin ciliate. Panicle narrowly oblong, 8–15 cm, longest internodes 3–5 cm; branches erect or curved ascending (sometimes spreading in fruit), 2 or 3(–5) per node, slender, scabrid angled from base, longest 2–6 cm with 5–15 spikelets in distal 1/2. Spikelets oblong to ovate, green, 4–5 mm, florets 3 or 4; vivipary absent; rachilla internodes 0.6–0.9 mm, glabrous; glumes slightly unequal, lanceolate, keel and veins distally scabrid, lower glume 2–2.4 mm, 1-veined, apex acuminate, upper glume oblong to lanceolate, 2.2–2.8 mm long, 3-veined, apex acuminate; lemmas 2.8–3.2 mm, keel villous for 3/4 of length, marginal veins to 1/2, area between veins glabrous or sparsely pilulose near keel; callus webbed; paleas distinctly shorter than the lemma, keels pilulose. Anthers (0.3–)0.4–0.7 mm. Fl. Jun–Jul. 2n = 28.

Shady and moist forest openings, grassy places. Hebei, Zhejiang [Japan, Korea].

Records from Sichuan and Yunnan in FRPS (9(2): 155. 2002) were based on misidentifications. This species has the pilulose ligules and branches scabrid from the base characteristic of Poa acroleuca, but the branches are shorter and erect to steeply ascending, and the lemmas are somewhat longer and usually glabrous or with a few hairs between the veins.