GrassBase - The Online World Grass Flora

Descriptions

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

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

Poa uruguayensis

HABIT Perennial; caespitose. Basal innovations intravaginal. Culms erect; 40–50 cm long; 2 -noded. Culm-nodes glabrous. Leaf-sheaths glabrous on surface. Ligule an eciliate membrane; 2–4 mm long; 1 mm long on basal shoots. Leaf-blades 10–15 cm long; 1–2 mm wide. Leaf-blade surface glabrous.

INFLORESCENCE Dioecious. Inflorescence a panicle.

Panicle open; ovate, or pyramidal; 8–12 cm long; 3–5 cm wide. Primary panicle branches whorled at lower nodes.

Spikelets solitary. Fertile spikelets pedicelled.

FERTILE SPIKELETS Spikelets comprising 6–7 fertile florets; with diminished florets at the apex. Spikelets oblong; laterally compressed; 6–8 mm long; breaking up at maturity; disarticulating below each fertile floret. Rhachilla internodes sparsely hairy. Floret callus woolly.

GLUMES Glumes persistent; similar; shorter than spikelet. Lower glume lanceolate; 3.5 mm long; 0.75 length of upper glume; membranous; 1-keeled; 1 -veined. Lower glume primary vein scabrous. Lower glume lateral veins absent. Lower glume apex acute. Upper glume ovate; 4.5 mm long; 0.75 length of adjacent fertile lemma; membranous; 1-keeled; 3 -veined. Upper glume primary vein scabrous. Upper glume apex acute.

FLORETS Fertile florets female. Fertile lemma ovate; 5.5 mm long; membranous; keeled; 5 -veined. Lemma midvein scaberulous; ciliolate; hairy below. Lemma margins ciliolate; hairy below. Lemma apex acute. Palea 3.5–4 mm long. Palea keels ciliolate. Apical sterile florets resembling fertile though underdeveloped.

FLOWER Lodicules 2; membranous. Anthers 3; 2.5 mm long.

FRUIT Caryopsis with adherent pericarp. Hilum punctiform.

MALE Male inflorescence similar to female. Male spikelets resembling female; 6–8 flowered. Male spikelet lemma 3–4 mm long.

DISTRIBUTION South America: southern South America.

NOTES Poeae. Parodi 1995.

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