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.

Agropyron uncinatum

HABIT Perennial; caespitose. Butt sheaths persistent and investing base of culm; with fibrous dead sheaths. Basal innovations intravaginal. Culms erect; 30–80 cm long. Culm-internodes distally glabrous. Culm-nodes pallid, or brown. Lateral branches lacking. Leaf-sheaths pubescent, or pilose. Ligule an eciliate membrane; 0.5–1 mm long; erose. Leaf-blades involute; 12–25 cm long; 1–2 mm wide. Leaf-blade surface pilose; hairy on both sides.

INFLORESCENCE Inflorescence composed of racemes. Peduncle 10–25 cm long; pubescent above.

Racemes 1; single; bilateral; 2–3 cm long; bearing few fertile spikelets; bearing 3–5 fertile spikelets on each. Rhachis flattened; pubescent on surface; terminating in a barren extension; extension bristle-like; extension 5–6 mm long. Spikelet packing broadside to rhachis. Rhachis internodes linear.

Spikelets appressed (anthesis), or spreading to deflexed (fruiting); solitary. Fertile spikelets pedicelled. Pedicels oblong; 1 mm long; pubescent.

FERTILE SPIKELETS Spikelets comprising 4–5 fertile florets; with diminished florets at the apex. Spikelets lanceolate; laterally compressed; 15–17 mm long; breaking up at maturity; disarticulating below each fertile floret. Rhachilla internodes 0.5–1 mm long; pubescent. Floret callus glabrous; disarticulating obliquely.

GLUMES Glumes persistent; similar; shorter than spikelet. Lower glume linear; 7–9 mm long; 1 length of upper glume; coriaceous; 1-keeled; 3 -veined. Lower glume apex acuminate; muticous, or awned; 1 -awned. Lower glume awn 0.5 mm long; hooked. Upper glume linear; 7.7–8 mm long; 0.5–0.66 length of adjacent fertile lemma; coriaceous; 1-keeled; 3–5 -veined. Upper glume apex acuminate; muticous, or awned; 1 -awned. Upper glume awn 0.5 mm long (hooked).

FLORETS Fertile lemma lanceolate; 12–15 mm long; coriaceous; keeled; 10–14 -veined. Lemma lateral veins more or less parallel. Lemma surface pubescent. Lemma apex acuminate; awned; 1 -awned. Principal lemma awn hooked; 1 mm long overall. Palea 7.5–10 mm long. Palea keels ciliate. Palea surface pubescent; hairy on back and on flanks. Apical sterile florets resembling fertile though underdeveloped.

FLOWER Lodicules 2; membranous. Anthers 3; 2–2.5 mm long; retained within floret. Stigmas 2.

FRUIT Caryopsis with adherent pericarp. Disseminule comprising a floret.

DISTRIBUTION Asia-tropical: Papuasia.

NOTES Triticeae. Veldkamp 1994.

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