Common Hardgrass

1000-1700 m.

Annual forming small dense tuft. Culms ascending or decumbent, 5–15 cm tall. Leaf sheaths smooth, glabrous, lower papery, whitish; leaf blades flat, 1.5–7 cm × 2–4 mm, glabrous, adaxial surface scabrid; ligule 1–3 mm, acute. Panicle elliptic-oblong in outline, dense, stiff, 1–5 cm, scarcely exserted from uppermost leaf sheath; branches bearing a single spikelet or shortly racemose near middle. Spikelets narrowly oblong, 6–10 mm, florets 3–5, lower 2–3 fertile, upper male or sterile; glumes ovate-oblong, lower glume 2–3 mm, upper glume 3.5–5 mm; lemmas ovate-oblong, lowest 4.8–6 mm, the upper much shorter, all veins prominent, apex obtuse to emarginate. Anthers 0.8–1.3 mm. Caryopsis 2.5–3.5 mm, brown. 2n = 14.

Tufted annual; culms up to 16 cm high, procumbent to erect. Leaf-blades 1.5-7 cm long, 2-4 mm wide, glabrous, scaberulous on the margins. Inflorescence 1-4 cm long, rigid, ± secund; pedicels stout, up to 1 mm long. Spikelets 6-10 mm long, narrowly oblong, crowded, glumes somewhat asymmetrical, glabrous, oblong-ovate, with broad hyaline margins, the lower 2-3 mm long, obtuse to emarginate, (1-)3(-5)-nerved; the upper 3.5-5 mm long, rounded to emarginate, (5-)7-9-nerved; lowest lemma 4.8-6 mm long, the upper much shorter, glabrous, rounded to emarginate, sometimes very shortly mucronate.

Xinjiang (Tian Shan) [Kazakhstan, Kyrgyzstan, Pakistan, Russia, Tajikistan, Turkmenistan, Uzbekistan; SW Asia, C and S Europe; introduced in Australia and the United States].

Distribution: Pakistan (N.W.F.P. & Kashmir); Mediterranean region, southern USSR and the Middle East.

Fl. & Fr. Per.: April-May.

Hill slopes; 500–1000 m.

Cynosurus durus Linnaeus, Sp. Pl. 1: 72. 1753.

Annuals, Terrestrial, not aquatic, Stems trailing, spreading or prostrate, Stems geniculate, decumbent, or lax, sometimes rooting at nodes, Stems caespitose, tufted, or clustered, Stems terete, round in cross section, or polygonal, Stems compressed, flattened, or sulcate, Stem internodes hollow, Stems with inflorescence less than 1 m tall, Stems, culms, or scapes exceeding basal leaves, Leaves mostly cauline, Leaves conspicuously 2-ranked, distichous, Leaves sheathing at base, Leaf sheath mostly closed, Leaf sheath mostly open, or loose, Leaf sheath smooth, glabrous , Leaf sheath or blade keeled, Leaf sheath and blade differentiated, Leaf blades linear, Leaf blades very narrow or filiform, less than 2 mm wide, Leaf blades 2-10 mm wide, Leaf blades mostly flat, Leaf blades mostly glabrous, Leaf blades scabrous, roughened, or wrinkled, Ligule present, Ligule an unfringed eciliate membrane, Inflorescence terminal, Inflorescence racemose, Inflorescence simple spikes, Inflorescence solitary, with 1 spike, fascicle, glomerule, head, or cluster per stem or culm, Inflorescence a panicle with narrowly racemose or spicate branches, Inflorescence single raceme, fascicle or spike, Inflorescence branches 1-sided, Rachis angular, Flowers bisexual, Spikelets sessile or subsessile, Spikelets laterally compressed, Inflorescence or spikelets partially hidden in leaf sheaths, subtended by spatheole, Spikelet less than 3 mm wide, Spikelets with 3-7 florets, Spikelets solitary at rachis nodes, Spikelets distichously arranged, Spikelets all alike and fertil le, Spikelets bisexual, Spikelets disarticulating above the glumes, glumes persistent, Spikelets disarticulating below the glumes, Spikelets disarticulating beneath or between the florets, Spikelets falling with parts of disarticulating rachis or pedicel, Spikelets secund, in rows on one side of rachis, Rachilla or pedicel glabrous, Glumes present, empty bracts, Glumes 2 clearly present, Glumes distinctly unequal, Glumes shorter than adjacent lemma, Glumes keeled or winged, Glumes 3 nerved, Glumes 4-7 nerved, Lemma coriaceous, firmer or thicker in texture than the glumes, Lemma 5-7 nerved, Lemma glabrous, Lemma apex truncate, rounded, or obtuse, Lemma awnless, Lemma margins thin, lying flat, Lemma straight, Palea present, well developed, Palea membranous, hyaline, Palea shorter than lemma, Palea 2 nerved or 2 keeled, Palea keels winged, scabrous, or ciliate, Stamens 3, Styles 2-fid, deeply 2-branched, Stigmas 2, Fruit - caryopsis.

Sclerochloa dura is a species of grass known by the common names common hardgrass and fairground grass. It is native to Eurasia, and it is known in parts of North America and Australia as an introduced species and a common weed of disturbed, high-traffic areas such as parking lots, roadsides, and playing fields. It is a sturdy annual grass forming low, flat clumps of short stems, some prostrate and some upright. The flat, overlapping leaf blades are a few centimeters long. The inflorescence is a crowded, one-sided series of flattened spikelets.