GrassBase - The Online World Grass Flora


W.D. Clayton, M. Vorontsova, K.T. Harman & H. Williamson

© Copyright The Board of Trustees, Royal Botanic Gardens, Kew.

Cortaderia rudiuscula

HABIT Perennial; caespitose. Culms 50–250 cm long. Leaf-sheaths outer margin hairy. Ligule a fringe of hairs; 0.5–2 mm long. Leaf-blades 100–185 cm long; 5–10 mm wide. Leaf-blade surface scabrous; rough on both sides. Leaf-blade margins scabrous.

INFLORESCENCE Gynodioecious ("male", in this context, indicating the bisexual state), or dioecious (by loss of viability in bisexual plants). Inflorescence a panicle.

Panicle open; oblong; dense; 15–70 cm long. Primary panicle branches 20–35 cm long.

Spikelets solitary. Fertile spikelets pedicelled. Male spikelets pedicelled. Pedicels filiform; scabrous.

FERTILE SPIKELETS Spikelets comprising 2–5(–8) fertile florets; with diminished florets at the apex. Spikelets lanceolate; laterally compressed; 10–16 mm long; breaking up at maturity; disarticulating below each fertile floret. Floret callus elongated; 0.5 mm long; pilose.

GLUMES Glumes similar; shorter than spikelet; similar to fertile lemma in texture; shiny. Lower glume lanceolate; 7–12 mm long; 1 length of upper glume; hyaline; without keels; 1 -veined. Lower glume lateral veins absent. Lower glume apex entire, or dentate; 2 -fid; attenuate. Upper glume lanceolate; 9–13 mm long; 1 length of adjacent fertile lemma; hyaline; without keels; 1 -veined. Upper glume lateral veins absent. Upper glume apex entire, or dentate; 2 -fid; attenuate.

FLORETS Fertile florets female. Fertile lemma lanceolate; 9–12 mm long; hyaline; shiny; without keel; 3 -veined. Lemma surface villous. Lemma hairs 5–8 mm long. Lemma apex dentate; 2 -fid; acuminate; muticous, or mucronate, or awned; 1 -awned. Principal lemma awn from a sinus; 0–2 mm long overall. Palea 3.5–4.5 mm long; 0.33–0.5 length of lemma; hyaline; 2 -veined. Palea keels scabrous. Apical sterile florets resembling fertile though underdeveloped.

FLOWER Lodicules 2; cuneate; 0.5 mm long; fleshy; ciliate. Anthers 3; 3 mm long. Staminodes present; 1–1.2 mm long.

FRUIT Caryopsis with adherent pericarp; 2.5 mm long.

MALE Male inflorescence nominally bisexual similar to female; a panicle. Male spikelets distinct from female (less hairy); hairy (hairs 2–3mm).

DISTRIBUTION South America: western South America and southern South America.

NOTES Arundineae. Fl Pat 1993.

Please cite this publication as detailed in How to Cite Version: 3rd February 2016.