Phalaris arundinacea L.
reed canary grass
Robust perennials, 60-200 cm, with long-creeping rhizomes. Leaf-sheath chartaceous, glabrous, striate, light brown. Ligule 2.5-7.5-(10) mm, entire, but soon lacerate. Leaf-blade 20-40 cm × 8-20 mm, ribs numerous, fine, adaxially smooth but scabrid near tip, abaxially with strong midrib near base, ribs densely, minutely scabrid; margins minutely scabrid, long-narrowed to scabrid, acute tip. Culm 50-180 cm. Panicle 9-30 × 1.5-4 cm, lanceolate or oblong, lobed below; rachis smooth below, scabrid above, branches scabrid, spreading at anthesis. Spikelets 4-5.5 mm, pale green or purplish. Glumes ± equal, 3-nerved, lanceolate, keeled but not winged, acute to acuminate, minutely scabrid, rarely lower glume with minute hairs near margin. Ø florets: lemmas equal, 1.3-1.6 mm, narrow, short-hairy. ⚥ floret: lemma 3-4 mm, broadly keeled, lanceolate, acute, firm and shining below, short-hairy above; palea much narrower than lemma; anthers (2)-2.5-3.2 mm; caryopsis c. 2 × 1 mm.
N.: North Auckland, Waikato, Manawatu, southern Wairarapa; S.: Canterbury, Otago, local in Nelson and Westland. Waste land, road margins, and damp or swampy ground.
Naturalised.
Indigenous to temperate Eurasia and North America.
The variegated form, P. arundinacea var. picta L. with cream-striped leaves, is cultivated as an ornamental and has escaped in many places.
