Lachnagrostis filiformis (G.Forst.) Trin.
≡Avena filiformis G.Forst. Prodr. 9 (1786)
≡Agrostis filiformis (G.Forst.) Spreng. in Biehler Pl. Nov. Herb. Spreng. 7 (1807) non Vill. (1787)
≡Calamagrostis filiformis (G.Forst.) Cockayne N.Z. Dept Lands Rep. Bot. Surv. Tongariro Natl Park 35 (1908) non Griseb. (1868)
≡Deyeuxia filiformis (G.Forst.) Petrie, in Chilton Subantarct. Is N.Z. 2: 474 (1909) non Hook.f. (1896)
≡Agrostis avenacea J.F.Gmel., Syst. Nat. 2, 1: 171 (1791)
≡Lachnagrostis avenacea (J.F.Gmel.) Veldkamp, Blumea 37: 230 (1992) nom. superfl.
≡Agrostis forsteri Roem. et Schult., Syst. Veg. 2: 359 (1817) nom. superfl.
≡Lachnagrostis forsteri (Roem. et Schult.) Trin. Gram. Unifl. 217 (1824) nom. superfl.
≡Deyeuxia forsteri (Roem. et Schult.) Kunth, Révis. Gram. 1: 77 (1829) nom. superfl.
≡Agrostis solandri F.Muell. Veg. Chatham Is 60 (1864) nom. superfl.
≡Lachnagrostis filiformis (G.Forst.) Trin. var. filiformis [autonym, Zotov Rec. Dom. Mus. 5: 142 (1965)];
Lectotype: B (Herb. Willdenow no. 2208)! Forster [Herb. Forster ex Sprengel], Habitat in Nova Zeelandia (designated by Edgar 1995 op. cit. p. 20).
New Zealand wind grass
Open, bluish green or light green, annual or short-lived perennial tufts, (12)-20-70 cm, whole plant often withering early and culms not breaking up below panicle; branching intravaginal. Leaf-sheath firmly membranous, distinctly ribbed, glabrous below, very finely scabrid above, light green, later light brown. Ligule (1)-2-5 mm, oblong, rounded or tapered, later lacerate, abaxially with sparse prickle-teeth. Leaf-blade 2.5-8-(18) cm × 1.5-3 mm, usually flat, sometimes involute and 0.5-1 mm diam., glabrous, or ribs scabrid; margins very finely scabrid, tip fine, acute. Culm 10-35 cm, erect to spreading, internodes usually densely, minutely scabrid, occasionally smooth. Panicle 9-30 × (0.5)-2-25 cm, delicate, enclosed at base by the uppermost leaf-sheath, at first contracted, later very lax; branches filiform, numerous, unequal, very finely scabrid, primary branches naked for much of their length, with spikelets in clusters of 2-several, towards tips of the much shorter capillary secondary branchlets. Spikelets 2.5-3.5-(4.2) mm, pale silvery green to purplish. Glumes subequal, acute to acuminate, usually glabrous, membranous, very narrow linear-lanceolate, lower glume usually slightly longer and more acuminate; keel scabrid almost to base. Lemma 1.3-2-(2.3) mm, ½-⅔ length of glumes, 5-nerved, moderately covered with very short hairs, oblong-ovate, glabrous near hyaline, truncate, erose apex, lateral nerves very shortly excurrent; awn 3-6 mm, geniculate, ± middorsal or from c. upper ⅓. Palea ¾-⅘ length of lemma, keels c. 0.1 mm apart, apex subobtuse. Callus ringed by minute hairs 0.3-0.4 mm, to ¼ length of lemma. Rachilla prolongation 0, or to c. 0.3 mm tipped with hairs to c. 0.8 mm. Lodicules 0.5-0.9 mm, linear, acute. Anthers 0.2-0.5 mm. Caryopsis 0.8-1.3 × 0.3-0.5 mm.
N.: throughout; S.: scattered throughout near coast, and on lake margins inland, once recorded from the margin of a saline area near Alexandra; St.; K., Three Kings Is, Ch. In damp ground, often on lake margins, also in disturbed ground and on roadsides; usually lowland, occasionally montane.
Indigenous.
Also indigenous to Australia, New Guinea and Easter Id; naturalised in South America, South Africa, and Malesia.
The name Agrostis aemula R.Br. was applied by Buchanan. J. Indig. Grasses N.Z. t. 21 (1879) to New Zealand plants of L. filiformis but L. aemula (R.Br.) Trin. of Australia is a coarser grass than L. filiformis with larger spikelets and a more spreading panicle.
