Agrostis castellana Boiss. & Reut.

Grey-green, rather fine-leaved perennials, forming tufts 30–90 cm, with long slender rhizomes; branching intravaginal. Leaf-sheath glabrous, brownish green or purplish. Ligule 0.7–2 mm, or up to 3 mm in culm leaves, taller than wide, somewhat tapered or rounded, minutely ciliate. Leaf-blade 4–16 cm × 1.5–4 mm, flat, finely scabrid, adaxially finely ribbed; margins scabrid, tip acute. Culm erect, internodes glabrous. Panicle 10–24 cm, linear-lanceolate to spreading, later more contracted; rachis, branches and pedicels sparsely scabrid to almost smooth. Spikelets 2–3 mm, grey-green to purplish; terminal spikelets usually with awned, 5-nerved lemmas, and lateral spikelets with awnless, 3–5-nerved lemmas. Glumes subequal, elliptic-lanceolate, acute or acuminate; lower with keel scabrid in upper ½, upper slightly shorter, smooth to scabrid on keel near tip. Lemma 1.6–2.2 mm, (3)–5-nerved, ovate-oblong, truncate-lobulate, the outer lateral nerves usually minutely excurrent, awned lemmas often with a few hairs in lower ½ near margin, awnless lemmas glabrous; awn, when present, from near base of lemma and ˜ lemma or up to twice length of lemma, occasionally awn very minute, middorsal or subapical and not projecting beyond lemma. Palea ½-⅔ length of lemma, apex shallowly bifid. Callus with minute tufts of hairs on either side, or sometimes glabrous in spikelets with awnless, 3-nerved, glabrous lemmas. Rachilla sometimes prolonged and tipped with a small tuft of hairs in awned spikelets. Anthers 1–1.5 mm. Caryopsis c. 1 × 0.4 mm.

[From: Edgar and Connor (2000) Flora of New Zealand. Volume 5 (second printing).]