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.

Poa bajaensis

HABIT Perennial; caespitose; clumped densely. Butt sheaths papery; persistent and investing base of culm. Basal innovations intravaginal. Culms erect; 20–50 cm long. Leaf-sheaths open for most of their length; with 0.33 of their length closed; 8–15 cm long; keeled; antrorsely scabrous. Ligule an eciliate membrane; 0.25–1.5(–2) mm long; scaberulous on abaxial surface; truncate, or obtuse. Leaf-blades flat, or conduplicate; 1–4 cm long; 1.5–2.75 mm wide. Leaf-blade surface smooth, or scaberulous; rough on both sides. Leaf-blade apex abruptly acute; hooded.

INFLORESCENCE Inflorescence a panicle.

Panicle open; ovate; 4–13 cm long. Primary panicle branches spreading, or reflexed; 2–5 -nate; 3–7 cm long; bearing 5–15 fertile spikelets on each lower branch. Panicle axis with lower internodes 1.8–3.9(–5.2) cm long; smooth. Panicle branches smooth, or scaberulous.

Spikelets solitary. Fertile spikelets pedicelled.

FERTILE SPIKELETS Spikelets comprising (1–)2–4(–6) fertile florets; with diminished florets at the apex. Spikelets ovate; laterally compressed; 3.75–8 mm long; breaking up at maturity; disarticulating below each fertile floret. Rhachilla internodes 1.25–2 mm long; smooth. Floret callus glabrous, or woolly.

GLUMES Glumes persistent; similar; with lower narrower than upper; shorter than spikelet. Lower glume lanceolate; 2.5–3 mm long; 0.9 length of upper glume; membranous; 1-keeled; 1(–3) -veined. Lower glume primary vein smooth, or scaberulous. Lower glume lateral veins absent, or obscure. Lower glume surface smooth, or asperulous; rough on veins, or between veins. Lower glume apex acute. Upper glume lanceolate; 2.8–3.8 mm long; 0.5–0.75 length of adjacent fertile lemma; membranous; 1-keeled; 3 -veined. Upper glume primary vein smooth, or scaberulous. Upper glume surface smooth, or asperulous; rough on veins, or between veins. Upper glume apex acute.

FLORETS Fertile lemma ovate; 3.2–4.2 mm long; membranous; keeled; 5 -veined. Lemma midvein scaberulous. Lemma lateral veins obscure. Lemma surface glabrous, or puberulous; hairy below. Lemma hairs 0.2–0.5 mm long. Lemma apex acute. Palea 1 length of lemma. Palea keels smooth, or scaberulous. Palea surface glabrous, or puberulous; hairy on back; hairy in the middle. Apical sterile florets resembling fertile though underdeveloped.

FLOWER Lodicules 2; membranous. Anthers 3; 1.7–3.2 mm long.

FRUIT Caryopsis with adherent pericarp. Hilum punctiform.

DISTRIBUTION North America: Mexico.

NOTES Poeae. Soreng 2003.

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