Classification
 Nomenclature
Scientific Name:
Holcus lanatus L., Sp. Pl. 1048 (1753)
Vernacular Name(s):
Yorkshire fog
 Description

Tufted, sometimes stoloniferous, softly hairy, greyish green perennials, 35–110 cm. Leaf-sheath firmly membranous, striate, ± keeled above near ligule, villous with long, fine, silky hairs, basal sheaths often purplish. Ligule (0.6)–1–3 mm, ± truncate, denticulate, apex finely ciliate and occasionally with a few long hairs, abaxially villous. Leaf-blade (2.5)–4.5–15–(20) cm × (1.5)–3–10 mm, pubescent and with longer soft hairs, narrowed to acuminate tip; margins finely ciliate, and with longer hairs. Culm erect, or ascending from geniculate base, nodes and internodes pubescent. Panicle 4–18 × 1.5–7 cm, lanceolate, ovoid or sometimes oblong, dense to lax, erect or nodding; rachis and branches pubescent. Spikelets 3.8–5.5 mm, whitish, pale green, or purplish. Glumes stiff-ciliate on keels and lateral nerves of upper glume, elsewhere minutely scabrid to shortly pubescent; lower sometimes slightly shorter, narrow-lanceolate, acute to mucronate, upper broader, elliptic, mucronate, or awned to 0.8 mm. Lemma 2–2.7 mm, elliptic-lanceolate, glabrous, shining, keel sparsely finely prickle-toothed, apex minutely ciliate-scabrid; lower lemma awnless, upper lemma narrower, awn stout, 1.4–2.8 mm, inserted c. 0.4 mm below tip of lemma, becoming recurved and uncinate. Palea keels sparsely short-ciliate above, apex obtusely lobed, minutely ciliate. Callus hairs few, to 1 mm. Rachilla glabrous. Anthers 1–2.2 mm. Caryopsis 1–1.5 × 0.4–0.5 mm.

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

 Biostatus
Exotic
 Bibliography
Howell, C. 2008: Consolidated list of environmental weeds in New Zealand. DOC Research & Development Series 292: 42.
Linnaeus, C. 1753: Species Plantarum. Impensis Laurentii Salvii, Stockholm.