Common name
Indian Bluegrass

Derivation
Bothriochloa Kuntze, Revis. Gen. Pl. 2: 762 (1891); from the Greek bothros (pit) and chloa (grass), alluding to the pitted glumes.

pertusa- Latin for with a pit, alluding to the deep pit on the abaxial surface of the lower glume.

Published in
Ann. Soc. Linn. Lyon 76: 164 (1931).

Habit
Perennial, mat forming. Stolons present. Culms erect or geniculately ascending or prostrate, 15–70 cm tall, rooting from lower nodes. Mid-culm nodes glabrous or bearded. Ligule a fringed membrane. Leaf-blades 5–30 cm long, 2.5–5 mm wide. Leaf-blade surface glabrous or hirsute.

Inflorescence
Inflorescence subdigitate, with ramose branches. Racemes 3–8(–13), 2.5–5(–7.5) cm long. Central inflorescence axis 1–3 cm long. Rhachis fragile at the nodes, flattened, villous on margins. Raceme internodes linear. Raceme internode tip transverse.

Spikelets
Spikelets in pairs, one sessile and fertile and the other (companion) spikelet pedicelled. Pedicels linear, flattened, with a translucent median line (also present in internodes), villous. Companion spikelets developed, sometimes male or sterile, containing empty lemmas or male, elliptic, 3.8 mm long, as long as fertile. Companion spikelet glumes pitted (1–2 pits), glabrous, ciliate on margins. Companion spikelet lemmas enclosed by glumes. Fertile spikelets 2-flowered, comprising 1 fertile floret, lower floret sterile, upper fertile, without rhachilla extension, elliptic, dorsally compressed, 3.5–4.5 mm long, falling entire, deciduous with accessory branch structures. Spikelet callus pilose, base obtuse, attached transversely.

Glumes
Glumes dissimilar, firmer than fertile lemma, shiny. Lower glume elliptic, 100% of length of spikelet, cartilaginous, keel-less except near apex, 3–7-nerved. Lower glume surface flat. Lower glume surface pitted, pilose, hairy at base. Lower glume margins ciliate. Upper glume lanceolate, 1-keeled.

Florets
Basal sterile floret 1, without significant palea. Lemma of lower sterile floret oblong or ovate, hyaline. Fertile lemma linear, 1.8 mm long, hyaline. Lemma apex entire or lobed, 2-fid,1-awned. Median (principal) awn apical, geniculate, 15–20 mm long overall, with a twisted column. Column glabrous. Palea absent or minute. Anthers 3, 2.2 mm long.

Continental Distribution:
Africa, Temperate Asia, Tropical Asia, Australasia, Pacific, North America, South America.

Australian Distribution:
Western Australia, Northern Territory, Queensland.

Western Australia: Fitzgerald, Dampier, Avon. Northern Territory: Darwin & Gulf. Queensland: Cook, Burke, North Kennedy, South Kennedy, Port Curtis, Leichhardt, Darling Downs, Mitchell, Warrego.

Classification. (GPWG 2001):
Panicoideae: Andropogoneae

Notes
Introduced to Australia where it is a good fodder grass in regions of moderate to low fertility soils. It is naturalised fairly widely in tropical N.T. Qld and W.A. Native from India to Indonesia. Flowers Feb.–Nov.

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