Polypogon viridis (Gouan) Breistr.
water bent
Perennials or annuals, 15-50-(90) cm, loosely tufted, often with creeping stolons rooting at nodes. Leaf-sheath chartaceous, striate, glabrous, greyish green. Ligule 1.5-5.5 mm, truncate, erose, ciliate, abaxially minutely scabrid. Leaf-blade 2.5-18 cm × 2-9 mm, linear-lanceolate, finely striate, scabrid, tip acute. Culm 9-50 cm, decumbent and rooting at lower nodes, internodes glabrous. Panicle 3-14 × 1-3-(5) cm, ± dense, oblong but much lobed, sometimes interrupted near base; rachis smooth, branches scabrid, with spikelets almost to base, pedicels densely scabrid, very short, disarticulating. Spikelets 1.5-1.9 mm, pale green or purplish, falling entire at maturity with portion of pedicel attached. Glumes equalling spikelet, 1-nerved, elliptic, entire, firmly membranous, scabrid, keel more prominent in upper ½, awnless. Lemma c. 1 mm, hyaline, broadly elliptic, glabrous, awnless, apex denticulate, minutely ciliate. Palea narrower than lemma, apex bifid, ciliate. Anthers 0.4-0.6 mm. Caryopsis 0.8-1 × 0.3-0.6 mm.
N.: scattered; S.: Nelson. Lowland in waste ground, roadsides and edges of ditches, often in damp places, occasionally a garden weed.
Naturalised.
Indigenous to Mediterranean and North Africa.
Though P. viridis has often been referred to Agrostis, as A. semiverticillata, because it lacks awns, its spikelets are deciduous at maturity, falling away with a portion of the pedicel attached, a feature regarded as diagnostic for Polypogon.
