Vasilis Teodoridis:
Poaceae | Poa
8. Poa annua Linnaeus; Sp. Pl. 1: 68. 1753.
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Poa annua f. reptans (Haussknecht) T. Koyama; P. annua var. reptans Haussknecht; P. crassinervis Honda.
Annuals; sometimes over wintering; infrequently stoloniferous. Culms loosely tufted; erect or oblique; often decumbent; often geniculate; soft; 6–30(–45) cm tall; smooth; nodes 1 or 2(or 3); 1(or 2) exserted. Leaf sheath slightly compressed; thin; smooth; uppermost closed for ca. 1/3 of length; blade light to dark green; flat or folded; thin; 2–12 cm x (0.8–)1–3.5 mm; margins slightly scabrid; apex acutely prow-tipped; ligules 0.6–3 mm; abaxially smooth; glabrous; apex obtuse; margin irregularly dentate; smooth. Panicle open; moderately congested; broadly ovoid to pyramidal; (1–)3–10 cm; as long as wide; branches ascending; spreading; or a few reflexed; 1 or 2(–3) per node; smooth; longest with usually 3–5 spikelets in distal 1/2. Spikelets ovate to oblong; dark to light green; (3–)4–5.5 mm; florets 3–5; distal fertile florets often female; vivipary absent; rachilla internodes 0.5–1.5 mm; smooth; glabrous; hidden or exposed; glumes unequal; smooth or rarely keeled with hooks; lower glume lanceolate and acute to subflabellate and obtuse; 1.5–2(–3) mm; 1-veined; upper glume elliptic; 2–3(–4) mm; 3-veined; the margin angled; lemmas ovate; 2.2–3.5 mm; apex and margins broadly membranous; intermediate veins prominent; keel and marginal; and usually intermediate; veins villous in the lower 1/2; rarely glabrous throughout; callus glabrous; palea keels smooth; densely pilulose to short villous. Anthers 0.6–1 mm; usually at least 2 x as long as wide; or vestigial. Fl. Apr–May; fr. Apr–Jul. 2n = 28.
Weed of disturbed; often moist and shady ground; near sea level to 4800 m. Anhui; Fujian; Gansu; Guangdong; Guangxi; Guizhou; Hainan; Hebei; Heilongjiang; Henan; Hubei; Hunan; Jiangsu; Jiangxi; Jilin; Liaoning; Nei Mongol; Qinghai; Shaanxi; Shandong; Shanxi; Sichuan; Taiwan; Xinjiang; Xizang; Yunnan; Zhejiang [Afghanistan; Bhutan; India; Indonesia; Japan; Kazakhstan; Korea; Kyrgyzstan; Malaysia; Mongolia; Myanmar; Nepal; New Guinea; Pakistan; Russia; Sri Lanka; Tajikistan; Turkmenistan; Uzbekistan; Vietnam; Africa; SW Asia; Australia; Europe; North and South America; Pacific Islands].
Vasilis Teodoridis:
Poaceae | Poa
8. Poa annua Linnaeus; Sp. Pl. 1: 68. 1753.
??? zao shu he
Poa annua f. reptans (Haussknecht) T. Koyama; P. annua var. reptans Haussknecht; P. crassinervis Honda.
Annuals; sometimes over wintering; infrequently stoloniferous. Culms loosely tufted; erect or oblique; often decumbent; often geniculate; soft; 6–30(–45) cm tall; smooth; nodes 1 or 2(or 3); 1(or 2) exserted. Leaf sheath slightly compressed; thin; smooth; uppermost closed for ca. 1/3 of length; blade light to dark green; flat or folded; thin; 2–12 cm x (0.8–)1–3.5 mm; margins slightly scabrid; apex acutely prow-tipped; ligules 0.6–3 mm; abaxially smooth; glabrous; apex obtuse; margin irregularly dentate; smooth. Panicle open; moderately congested; broadly ovoid to pyramidal; (1–)3–10 cm; as long as wide; branches ascending; spreading; or a few reflexed; 1 or 2(–3) per node; smooth; longest with usually 3–5 spikelets in distal 1/2. Spikelets ovate to oblong; dark to light green; (3–)4–5.5 mm; florets 3–5; distal fertile florets often female; vivipary absent; rachilla internodes 0.5–1.5 mm; smooth; glabrous; hidden or exposed; glumes unequal; smooth or rarely keeled with hooks; lower glume lanceolate and acute to subflabellate and obtuse; 1.5–2(–3) mm; 1-veined; upper glume elliptic; 2–3(–4) mm; 3-veined; the margin angled; lemmas ovate; 2.2–3.5 mm; apex and margins broadly membranous; intermediate veins prominent; keel and marginal; and usually intermediate; veins villous in the lower 1/2; rarely glabrous throughout; callus glabrous; palea keels smooth; densely pilulose to short villous. Anthers 0.6–1 mm; usually at least 2 x as long as wide; or vestigial. Fl. Apr–May; fr. Apr–Jul. 2n = 28.
Weed of disturbed; often moist and shady ground; near sea level to 4800 m. Anhui; Fujian; Gansu; Guangdong; Guangxi; Guizhou; Hainan; Hebei; Heilongjiang; Henan; Hubei; Hunan; Jiangsu; Jiangxi; Jilin; Liaoning; Nei Mongol; Qinghai; Shaanxi; Shandong; Shanxi; Sichuan; Taiwan; Xinjiang; Xizang; Yunnan; Zhejiang [Afghanistan; Bhutan; India; Indonesia; Japan; Kazakhstan; Korea; Kyrgyzstan; Malaysia; Mongolia; Myanmar; Nepal; New Guinea; Pakistan; Russia; Sri Lanka; Tajikistan; Turkmenistan; Uzbekistan; Vietnam; Africa; SW Asia; Australia; Europe; North and South America; Pacific Islands].