Guadua Trinii

HABIT:

• Perennial; caespitose.
• Rhizomes short; pachymorph.
• Culms leaning; 300–1000 cm long; 30–50 mm diam.; woody; with root thorns from the nodes.
• Culm-internodes semiterete; thick-walled; antrorsely scabrous.
• Lateral branches dendroid.
• Bud complement 1.
• Branch complement three; thinner than stem.
• Culm-sheaths deciduous.
• Culm-sheath blade inconspicuous.
• Leaf-sheath oral hairs setose.
• Ligule an eciliate membrane.
• Leaf-blade base with a brief petiole-like connection to sheath; petiole pubescent.
• Leaf-blades deciduous at the ligule; lanceolate; 5–15 cm long; 15–30 mm wide.
• Leaf-blade apex acuminate.

 

INFLORESCENCE:

• Synflorescence bractiferous; scanty; lax; with glumaceous subtending bracts; with axillary buds at base of spikelet; prophyllate below lateral spikelets.

 

FERTILE SPIKELETS:

• Spikelets comprising 6–8 fertile florets; with diminished florets at the apex.
• Spikelets lanceolate; laterally compressed; 20–30 mm long; breaking up at maturity; disarticulating below each fertile floret.
• Rhachilla internodes obscured by lemmas.

 

GLUMES:

• Glumes several; persistent; similar; shorter than spikelet.
• Upper glume ovate; coriaceous; without keels; 11–17 -veined.
• Upper glume apex acute.

 

FLORETS:

• Fertile lemma ovate; 10 mm long; coriaceous; without keel; 11–17 -veined.
• Lemma apex acute.
• Palea keels winged; conspicuously winged.
• Apical sterile florets resembling fertile though underdeveloped.

 

FLOWER:

• Lodicules 3; veined.
• Anthers 6.
• Stigmas 3.

 

FRUIT:

• Caryopsis with adherent pericarp.

 

DISTRIBUTION:

• Argentina
• Brazil
• Uruguay

Sources:
GrassBase - The Online World Grass Flora
INBAR (International Network for Bamboo and Rattan)