Australian Tropical Rainforest Plants - Online edition

Bothriochloa pertusa (L.) A.Camus


Weed
Grass
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Herbarium specimen. © DERM
Family

Camus, A.A. (1931) Annales de la Societe Linneenne de Lyons 76: 164.

Common name

Indian Blue Grass; Blue grass, Indian

Stem

Mat forming and stoloniferous. Culms erect, or geniculately ascending; 30-60 cm long; rooting from lower nodes.

Leaves

Leaf sheaths keeled; leaf blades linear, 5-20 × 0.1-0.4 cm, tubercle-based hairs on both surfaces or abaxial surface glabrous, apex acute; ligule 0.5-2 mm.

Flowers

Inflorescence composed of 3-8(-13) digitate racemes 2.5-5(-7.5) cm long. Central inflorescence axis 1-3 cm long. Rhachis fragile at the nodes, flattened and villous on the margins. Rhachis internodes linear with the tip transverse. Spikelets in pairs. Fertile spikelets sessile. Companion sterile spikelets pedicelled. Pedicels linear, flattened, with a translucent median line (also present in internodes), villous. Sterile spikelets well-developed, containing empty lemmas, or male; elliptic, 3.8 mm long, as long as the fertile spikelet. Companion sterile spikelet glumes pitted (1-2 pits), glabrous, ciliate on margins, enclosed by glumes. Fertile spikelets comprising of 1 basal sterile floret and 1 fertile floret; without rhachilla extension. Spikelets elliptic, dorsally compressed, 3.5-4.5 mm long, falling entire, deciduous with accessory branch structures. Spikelet callus pilose, base obtuse, attached transversely. Glumes dissimilar and exceeding apex of florets, firmer than fertile lemma, shiny. Lower glume elliptic, same length as spikelet, cartilaginous, without keels except near the apex; 5-7 -veined. Lower glume surface flat; pitted; pilose; hairy at base. Lower glume margins ciliate. Upper glume lanceolate and keeled. Basal sterile florets barren, without significant palea. Lemma of lower sterile floret oblong and hyaline. Fertile lemma linear, 1.8 mm long, hyaline, without keel. Lemma apex entire, awned. Principal lemma awn apical, geniculate, 15-20 mm long overall, with twisted columns. Column of lemma awn glabrous. Palea absent or minute.

Seedlings

Features not available.

Distribution and Ecology

Occurs in WA, NT, CYP, NEQ, CEQ and southwards to south-eastern Queensland. Altitudinal range from 50-760 m. Grows in disturbed areas and along roads in notophyll vineforest, deciduous vine thicket, Eucalypt woodland, beach scrub and wooded grassland. Also from Africa, China, India, Indo-China, Malesia, Pacific Islands, North America and South America.

Natural History & Notes

Highly esteemed as a fodder grass and can also be made into hay.

A weed of disturbed places and of cultivation.

RFK Code
4246
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