Scientific Name:
Leymus racemosus (Lam.) Tzvelev (1960)
  • Elymus racemosus Lam. (1792)
  • = Elymus giganteus Vahl, Symb. Bot. (Vahl) 3, 10 (1794)
  • Elymus arenarius var. giganteus (Vahl) Schmalh. (1890)
Vernacular Name(s):
Siberian lyme grass

Very robust, yellow-green or glaucous tufts, 75–150–(200) cm, with stout rhizomes, often forming large patches. Leaf-sheath glabrous or very sparsely very fine hairy, firmly chartaceous, yellowish, adaxially shining, shredding into fibres at maturity, with chartaceous glabrous auricles 1.5–3 mm. Ligule 1–2–(3.5) mm, rim-like, minutely ciliate. Leaf-blade 10–65 cm × 4.5–16 mm, flat, to involute above, abaxially sometimes with very short fine hairs above collar, otherwise glabrous, adaxially strongly ribbed and finely pubescent-scabrid there, narrowed to smooth, hard, pungent tip. Culm 50–110–(160) cm, stout, erect, internodes glabrous except below nodes. Spike 25–40–(50) × (1.5)–2–3.5 cm, stiff, erect, tapered above, spikelets in clusters of 3s to 5s at nodes, or occasionally some paired, well-spaced near base and imbricate above; rachis angled with fine hairs on angles. Spikelets 15–25 mm, 4–6-flowered, straw-coloured, included by glumes. Glumes equal, very narrow-lanceolate, 1–3-nerved, smooth, coriaceous, the long-acuminate tip produced into fine shining awn, becoming ± patent, asymmetric at base, margins sometimes sparsely scabrid, adaxially finely hairy especially centrally. Lemma 10–15.5 mm, 5–7-nerved, elliptic, abaxially silky-pubescent below, glabrous near acute apex, adaxially with appressed very short silky hairs. Palea ≈ lemma, interkeel glabrous, shortly ciliate at notched apex. Callus 0.5 mm, bearded with long hairs. Rachilla 3–4 mm, hairy. Lodicules 2 mm, very long ciliate. Anthers 4.5–6.5 mm, sometimes pollen-sterile. Gynoecium golden: ovary 2 mm, hair covered; stigma-styles 2.5 mm. Caryopsis c. 6.5 × 2 mm.

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

Barkworth, M.E.; Atkins, R.J. 1984: Leymus Hochst. (Gramineae: Triticeae) in North America: Taxonomy and Distribution. American Journal of Botany 71(5): 609–625.
Biosecurity New Zealand 2012: Regional Pest Management Strategies Database.
Howell, C. 2008: Consolidated list of environmental weeds in New Zealand. DOC Research & Development Series 292: 42.
Vahl, M. 1794: Symbolae botanicae. Part 3. Möller, Copenhagen.