Guadua incana

HABIT Perennial; caespitose. Rhizomes short; pachymorph. Culms erect; nodding at the tip; 1000–1500(–1800) cm long; 70–90(–120) mm diam.; woody; with root thorns from the nodes. Culm-internodes terete; hollow; (20–)30–55(–65) cm long; light green; distally pubescent; with reflexed hairs. Culm-nodes with distinct supra-nodal ridge. Lateral branches dendroid; intravaginal. Bud complement 1. Branch complement two, or three; with 1 branch dominant; thinner than stem. Culm-sheaths (19–)24–33 cm long; brown; hispid; with white hairs, or yellow hairs; hairy on margins; without auricles; setose on shoulders; shoulders with curved hairs; shoulders with 3–5 mm long hairs. Culm-sheath ligule 0.5–1 mm high; ciliolate. Culm-sheath blade triangular; demarcated but persistent; erect; (3.5–)5–10 cm long; 7–12 mm wide. Leaves 5–8(–10) per branch. Leaf-sheaths glabrous on surface to pubescent; outer margin hairy. Leaf-sheath oral hairs setose; curly; 4–5 mm long. Ligule an eciliate membrane, or a ciliolate membrane; 0.3–0.4 mm long; brown; pubescent on abaxial surface. Collar with external ligule. Leaf-blade base with a brief petiole-like connection to sheath; petiole 0.2–0.4 cm long; petiole glabrous. Leaf-blades linear, or lanceolate; (3.5–)11–13(–16) cm long; (7–)10–20(–22) mm wide. Leaf-blade midrib conspicuous. Leaf-blade venation prominent; with 13–15 secondary veins; with distinct cross veins. Leaf-blade surface pilose; sparsely hairy; hairy on both sides. Leaf-blade margins scabrous. Leaf-blade apex acuminate; apiculate (2–3 mm).

INFLORESCENCE Synflorescence bractiferous; clustered at the nodes; in untidy tufts; with glumaceous subtending bracts; with axillary buds at base of spikelet; prophyllate below lateral spikelets; leafless between clusters.

Fertile spikelets sessile.

FERTILE SPIKELETS Spikelets comprising 1–2 basal sterile florets; 5–7 fertile florets; with diminished florets at the apex. Spikelets linear, or lanceolate; laterally compressed; 20–40 mm long; 7 mm wide; breaking up at maturity; disarticulating below each fertile floret. Rhachilla internodes 3–4.5 mm long; pubescent.

GLUMES Glumes several; comprising 1–4(–5) gemmiferous bracts (or glumes); deciduous; similar; shorter than spikelet. Lower glume ovate; 5–9 mm long; 7–11 -veined. Lower glume surface pubescent. Lower glume apex acute; mucronate.

FLORETS Basal sterile florets similar; barren; with palea, or without significant palea; separately deciduous. Lemma of lower sterile floret similar to fertile lemma; lanceolate, or ovate; 6.5–8 mm long; 10–16 -veined; ciliolate on margins; mucronate. Fertile lemma lanceolate, or ovate; 9–11.5 mm long; 6–8 mm wide; coriaceous; without keel; 16–18 -veined. Lemma apex acute; mucronate. Palea 9–11 mm long; 0.9–1 length of lemma; 9–12 -veined. Palea keels winged; conspicuously winged. Palea surface puberulous; hairy on back. Apical sterile florets resembling fertile though underdeveloped.

FLOWER Lodicules 3; 2.5–5 mm long; veined; ciliate. Anthers 6; 4–5.2 mm long; anther tip apiculate. Filaments free. Stigmas 3.

FRUIT Caryopsis with adherent pericarp; fusiform; 7–9 mm long. Embryo 0.2 length of caryopsis.

DISTRIBUTION South America: western South America.

NOTES Bambuseae. Londono 2009.

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