Polypogon viridis
(Gouan) Breistr. Water BentStoloniferous perennial, culms ascending to erect, to 100 cm high. Leaf-blades flat, scabrous on both surfaces, to 15 cm long and 5 mm wide; sheaths smooth; ligules membranous, truncate, to 5 mm long. Inflorescence a rather dense panicle of several whorls of branchlets, the lower usually somewhat distant from the upper, to 12 cm long and 4 cm wide; spikelets disarticulating at maturity; glumes broadly acute, scabrous, sometimes ciliate along margins, 1.5–2.5 mm long; lemma ovate, c. 1 mm long, membranous, shallowly dentate; palea subequal to lemma. Flowers Sep.–Mar.
Wim, GleP, VVP, GipP, OtP, Gold, CVU, GGr, EGL, HSF, OtR. WA, SA, Qld, NSW, Tas. Native to the Mediterranean, but widely naturalised in temperate regions (e.g. Central Asia, South Africa, the Americas, New Zealand). Known from a few scattered localities, mostly in southern Victoria, e.g. Nhill, Hamilton, Essendon, Wonthaggi, Orbost, but probably more widespread. A weed of damp or wet sites, e.g. irrigation ditches, roadside drains etc. Sometimes treated as Agrostis viridis Gouan due largely to the lack of awned glumes (a feature of Polypogon), but the disarticulating spikelets and features of the lemma epidermis (the 'lack of a trichodium net') unite it with Polypogon. Molecular studies (e.g. Saarela et al. 2017) also support its placement in Polypogon.
Walsh, N.G. (1994). Poaceae. In: Walsh, N.G.; Entwisle, T.J., Flora of Victoria Vol. 2, Ferns and Allied Plants, Conifers and Monocotyledons, pp. 356–627. Inkata Press, Melbourne.
Saarela, J.M.; Bull, R.D.; Paradis, M.J.; Ebata, S.N.; Peterson, P.M.; Soreng, R.J.; Paszko, B. (2017). Molecular phylogenetics of cool-season grasses in the subtribes Agrostidinae, Anthoxanthinae, Aveninae, Brizinae, Calothecinae, Koeleriinae and Phalaridinae (Poaceae, Pooideae, Poeae, Poeae chloroplast group 1). Phytokeys 87: 1–139.
