乌库早熟禾 wu ku zao shu he

Poa ochotensis Trinius, Mém. Acad. Imp. Sci. St.-Pétersbourg, Sér. 6, Sci. Math. 1: 377. 1831; P. nemoralis Linnaeus subsp. ochotensis (Trinius) Tzelev; P. subaphylla Honda.

Culms 35–60 cm tall, slender, usually almost smooth under inflorescence, nodes 2–3(–4), uppermost node to 1/3 way up culm. Leaf sheaths longer than blade; blade narrowly linear, 1–1.5 mm wide, flat, scabrid; ligule (0.5–)1–2(–4) mm. Panicle narrow, sometimes almost spiciform, dense, 3–8 × 0.5–1.5 cm; basal branches 1/5–1/3 as long as panicle; rachilla warty, glabrous, rarely minutely pilose. Spikelets 3–5(–6) mm, florets 6 or 7; glumes narrowly lanceolate; lemma 3–3.5 mm, keel shortly villous for 1/2 of length, marginal veins for 1/3, other parts glabrous; callus nearly glabrous; palea sometimes pilulose between keels. 2n = 28, 42, 49.

Grassy places on slopes; 200–1000 m. Anhui, Gansu, Hebei, Heilongjiang, Henan, Jilin, Liaoning, Nei Mongol, Shaanxi, Shanxi [Japan, Korea, Mongolia, Russia (Far East)].

This taxon seems to be a stabilized hybrid between Poa sphondylodes and P. versicolor. It is treated here as a subspecies of P. versicolor because the characters of that species prevail. Material with a glabrous callus was described as P. subaphylla.

Most gatherings identified by Chinese, Japanese, and Korean botanists as Poa viridula Palibin seem to belong here. True P. viridula has not been recorded from China.