Rough Bluegrass

In Great Britain and/or Ireland:
Foodplant / parasite
Blumeria graminis parasitises live Poa trivialis

Plant / resting place / on
puparium of Cerodontha flavocingulata may be found on leaf of Poa trivialis
Other: major host/prey

Foodplant / miner
larva of Cerodontha fulvipes mines leaf -> sheath of Poa trivialis

Foodplant / gall
stroma of Epichlo causes gall of stem of Poa trivialis

Foodplant / saprobe
sessile, shielded apothecium of Micropeziza poae is saprobic on dead stem of Poa trivialis
Remarks: season: 8

Foodplant / saprobe
colony of Cercosporidium dematiaceous anamorph of Mycosphaerella recutita is saprobic on dead sheath of Poa trivialis

Foodplant / parasite
hypophyllous, long covered by epidermis telium of Puccinia brachypodii var. poae-nemoralis parasitises live leaf of Poa trivialis

Foodplant / parasite
linear telium of Puccinia graminis f.sp. poae parasitises live stem of Poa trivialis

Foodplant / parasite
plentiful, in short rows telium of Puccinia poarum parasitises live leaf of Poa trivialis

Foodplant / spot causer
Spermospora anamorph of Spermospora poagena causes spots on live leaf of Poa trivialis

Foodplant / saprobe
fruitbody of Typhula incarnata is saprobic on dying stem of Poa trivialis

Foodplant / parasite
mainly hypophyllous telium of Uromyces dactylidis parasitises live leaf of Poa trivialis

Poa trivialis is sometimes seeded as a pasture and lawn species. It establishes well in cool, moist, shady sites, including gardens, trails, adjacent woods, and disturbed ground. It is probably introduced in China. Two races (or species) are usually recognized, with subsp. tri-vialis far more widely dispersed beyond the native European–SW Asian range of the species.

Rough Meadow-grass is so named from its characteristically scaberulous leaf-sheaths. 1700-2700m.

Perennials, tufted, stoloniferous, shoots with or without beadlike swellings. Culms decumbent to geniculate, 20–100 cm tall, 1–2 mm in diam., nodes 3 or 4, scabrid below panicle and nodes. Lower leaf sheaths usually densely retrorsely scabrid, 8–15 cm, subequal to blade, uppermost closed for ca. 1/4 of length; blade flat, papery, 8–20 cm × 2–5 mm, surfaces scabrid, apex acuminate; ligule 3.5–10 mm, abaxially scabrid, acute to acuminate, collar smooth or scabrid, glabrous. Panicle oblong to pyramidal, 9–20 × 2–4 cm; branches obliquely ascending to spreading, 4–5 per node, densely scabrid throughout, longest ca. 4 cm with many spikelets crowded in distal 1/2, pedicels very short. Spikelets 2.5–3.5(–4) mm, florets 2 or 3; vivipary absent; glumes scabrid on keel, lower glume narrow, often sickle-shaped, 1.5–2 mm, 1-veined, upper glume 2.2–3 mm, 3-veined; lemmas ca. 2.5 mm, abaxial surface slightly arched, keel shortly villous for ca. 1/2 of length, marginal veins glabrous or pilulose to short-villous in lower 1/3, intermediate veins prominent, areas between veins minutely bumpy, glabrous; callus webbed, hairs long; palea subequal to lemma, minutely bumpy between keels, glabrous, keels minutely scabrid or bumpy. Anthers ca. 1.5 mm. Fl. and fr. May–Jul.

Loosely tufted perennial, often with extensively creeping stolons but without rhizomes; culms 20-100cm high, erect or spreading from a procumbent base. Leaf-blades flat, 3-20cm long, 2-4.5(-6)mm wide, rather thin and flaccid, abruptly and sharply pointed, scabrid on the margins and both surfaces, sometimes nearly smooth and shining; ligule pointed, 3.5-10mm long. Panicle ovate-pyra¬midal, (9-)15-25cm long, erect or nodding, very loose or contracted and rather dense; branches in clusters of 3-5(-7) at the lower nodes, scabrid. Spikelets 3-4-flowered, ovate or oblong, 3-4mm long, green, purplish or reddish; glumes unequal, the lower lanceolate, 2-3mm long, 1-nerved, the upper ovate, 2.5-3.5 mm long, 3-nerved; lemmas narrowly oblong in side view, 2.5-3.5mm long, acute, usually ciliate only on the keel, woolly at the base; palea a little shorter than the lemma, scabrid along the keels; anthers 1.5-2mm long.

Hebei, Jiangsu, Jiangxi, Nei Mongol, N Sichuan, Xinjiang [Afghanistan, Bhutan, India, Indonesia, Japan, Kazakhstan, Kyrgyzstan, Mongolia, Pakistan, Russia, Tajikistan, Turkmenistan, Uzbekistan; SW Asia, Europe; introduced in Africa, Australia, New Zealand, and North and South America].

Distribution: Pakistan (Baluchistan, N.W.F.P. & Kashmir); widespread in temperate regions of the northern hemisphere; extensively introduced elsewhere.

Fl. & Fr. Per.: July-August.

Moist places, grassy places on slopes; 1000–3500 m.

Perennials, Terrestrial, not aquatic, Stolons or runners present, Stems nodes swollen or brittle, Stems erect or ascend ing, Stems geniculate, decumbent, or lax, sometimes rooting at nodes, Stems caespitose, tufted, or clustered, Stems terete, round in cross section, or polygonal, Stem internodes hollow, Stems with inflorescence less than 1 m tall, Stems, culms, or scapes exceeding basal leaves, Leaves mostly basal, below middle of stem, Leaves conspicuously 2-ranked, distichous, Leaves sheathing at base, Leaf sheath mostly open, or loose, Leaf sheath smooth, glabrous, Leaf sheath and blade differentiated, Leaf blades linear, Leaf blades 2-10 mm wide, Leaf blades mostly flat, Leaf blades mostly glabrous, Ligule present, Ligule an unfringed eciliate membrane, Inflorescence terminal, Inflorescence an open panicle, openly paniculate, branches spreading, Inflorescence a contracted panicle, narrowly paniculate, branches appressed or ascending, Inflorescence solitary, with 1 spike, fascicle, glomerule, head, or cluster per stem or culm, Inflorescence with 2-10 branches, Inflorescence branches more than 10 to numerous, Lower panicle branches whorled, Flowers bisexual, Spikelets pedicellate, Spikelets laterally compressed, Spikelet less than 3 mm wide, Spikelets with 2 florets, Spikelets with 3-7 florets, Spikelets solitary at rachis nodes, Spikelets all alike and fertille, Spikelets bisexual, Spikelets disarticulating above the glumes, glumes persistent, Spikelets disarticulating beneath or between the florets, Rachilla or pedicel glabrous, Glumes present, empty bracts, Glumes 2 clearly present, Glumes equal or subequal, Glumes distinctly unequal, Glumes shorter than adjacent lemma, Glumes keeled or winged, Glumes 3 nerved, Lemmas thin, chartaceous, hyaline, cartilaginous, or membranous, Lemma similar in texture to glumes, Lemma 5-7 nerved, Lemma glabrous, Lemma body or surface hairy, Lemma apex acute or acuminate, Lemma awnless, Lemma margins thin, lying flat, Lemma straight, Callus or base of lemma evidently hairy, Callus hairs shorter than lemma, Lemma with long co bwebby white hairs, Palea present, well developed, Palea about equal to lemma, Palea 2 nerved or 2 keeled, Stamens 3, Styles 2-fid, deeply 2-branched, Stigmas 2, Fruit - caryopsis, Caryopsis ellipsoid, longitudinally grooved, hilum long-linear.

Poa trivialis (rough bluegrass; UK: rough-stalked meadow-grass or rough meadow-grass), is a perennial plant regarded in the US as an ornamental plant. It is part of the grass family.