Trisetum bertolonii

HABIT Perennial; caespitose. Butt sheaths persistent and investing base of culm; with compacted dead sheaths. Culms 20–25 cm long. Culm-internodes distally hirsute. Leaf-sheaths glabrous on surface. Ligule an eciliate membrane. Leaf-blades curved; filiform; involute; 3–12 cm long; 1 mm wide; stiff; grey-green. Leaf-blade surface pubescent; hairy adaxially. Leaf-blade margins unthickened.

INFLORESCENCE Inflorescence a panicle; comprising 20–40 fertile spikelets.

Panicle open; ovate; 2–6 cm long; 1–1.5 cm wide.

Spikelets solitary. Fertile spikelets pedicelled.

FERTILE SPIKELETS Spikelets comprising 2–3 fertile florets; with a barren rhachilla extension. Spikelets oblong; laterally compressed; 6.5–9 mm long; breaking up at maturity; disarticulating below each fertile floret. Rhachilla internodes pilose. Floret callus pubescent.

GLUMES Glumes persistent; similar; reaching apex of florets; thinner than fertile lemma; shiny; gaping. Lower glume lanceolate; 0.66 length of upper glume; membranous; 1-keeled; 1 -veined. Lower glume lateral veins absent. Lower glume apex acute. Upper glume lanceolate; 0.9–1 length of adjacent fertile lemma; membranous; 1-keeled; 3 -veined. Upper glume apex acute.

FLORETS Fertile lemma oblong; 4.8–7.5 mm long; membranous; shiny; keeled; 5 -veined. Lemma apex dentate; 2 -fid; awned; 3 -awned. Principal lemma awn dorsal; arising 0.5–0.6 way up back of lemma; geniculate; 9–13 mm long overall; with twisted column. Lateral lemma awns 1–2 mm long. Palea gaping; hyaline.

FLOWER Anthers 3; 2–2.5 mm long.

FRUIT Caryopsis with adherent pericarp. Hilum punctiform.

DISTRIBUTION Europe: southeastern.

NOTES Aveneae. Fl Eur 1995.

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