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.

Lachnagrostis adamsonii

HABIT Annual; caespitose. Culms erect, or geniculately ascending; 45–70 cm long; 5 -noded. Culm-internodes smooth, or scaberulous. Culm-nodes glabrous. Leaf-sheaths loose; scaberulous. Ligule an eciliate membrane; 3–5 mm long; scaberulous on abaxial surface; lacerate. Leaf-blades 8–25 cm long; 1–3.5 mm wide. Leaf-blade surface ribbed; scaberulous. Leaf-blade apex acuminate.

INFLORESCENCE Inflorescence a panicle; exserted, or embraced at base by subtending leaf. Peduncle retrorsely scabrous above.

Panicle open; pyramidal; 20–25 cm long. Primary panicle branches spreading; whorled at most nodes. Panicle branches capillary; scabrous.

Spikelets solitary. Fertile spikelets pedicelled. Pedicels clavate; 2–8 mm long; scabrous.

FERTILE SPIKELETS Spikelets comprising 1 fertile florets; with a barren rhachilla extension. Spikelets lanceolate, or elliptic; laterally compressed; 3–3.5 mm long; breaking up at maturity; disarticulating below each fertile floret. Floret callus pubescent.

GLUMES Glumes persistent; similar; exceeding apex of florets; firmer than fertile lemma; gaping. Lower glume lanceolate; 3–3.5 mm long; 1 length of upper glume; membranous; 1-keeled; 1 -veined. Lower glume primary vein scabrous. Lower glume lateral veins absent. Lower glume apex acute, or acuminate. Upper glume lanceolate; 3–3.5 mm long; membranous; 1-keeled; keeled above; 1 -veined. Upper glume primary vein scabrous. Upper glume lateral veins absent. Upper glume surface scabrous. Upper glume apex acute, or acuminate.

FLORETS Fertile lemma lanceolate; 2.5 mm long; hyaline; without keel; 5 -veined. Lemma lateral veins obscure; extending close to apex. Lemma apex dentate; 4 -fid; truncate; awned; 1 -awned. Principal lemma awn subapical; straight; 2 mm long overall. Palea 1 length of lemma; hyaline. Rhachilla extension 0.2–0.5 mm long; pilose.

FLOWER Lodicules 2; membranous. Anthers 3; 0.4–0.6 mm long.

FRUIT Caryopsis with adherent pericarp. Hilum linear.

DISTRIBUTION Australasia: Australia.

NOTES Aveneae. Vickery 1994.

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