Common name
Forest Bluegrass
Mountain Bluegrass

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

bladhii- after Pehr Johann Bladh who collected in China and South Africa before 1781.

Published in
Proc. Roy. Soc. Queensland 80: 62 (1969).

Common synonyms
Bothriochloa intermedia (R.Br.) A.Camus
Bothriochloa glabra (Roxb.) A.Camus

Habit
Perennial, tufted. Rhizomes short. Culms erect or geniculately ascending, 50–150 cm tall. Lateral branches simple or sparsely branched. Ligule an eciliate membrane. Leaf-blades 10–55 cm long, 2–12 mm wide.

Inflorescence
Inflorescence compound, a panicle of racemes, with ramose branches. Peduncle 10–15 cm long. Panicle 3–14 cm long. Racemes numerous, 1.8–5 cm long. Central inflorescence axis 0.3–2 cm long. Rhachis fragile at the nodes, flattened, ciliate 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), ciliate. Companion spikelets developed, male or sterile, comprising 2 subequal glumes without lemmas or containing empty lemmas or male, linear or lanceolate or oblong, 2.5–4 mm long, shorter than fertile, persistent. Companion spikelet glumes without depressions or pitted (1–3 pits), glabrous. Fertile spikelets 2-flowered, comprising 1 fertile floret, lower floret sterile, upper fertile, without rhachilla extension, elliptic or oblong, dorsally compressed, 3–4 mm long, falling entire, deciduous with accessory branch structures. Spikelet callus pilose, base obtuse, attached transversely.

Glumes
Glumes dissimilar, firmer than fertile lemma. Lower glume elliptic, 100% of length of spikelet, chartaceous, keel-less except near apex, 5–7-nerved. Lower glume surface flat. Lower glume surface without pits or pitted, pilose, hairy below. Lower glume apex acute. Upper glume lanceolate or oblong, 1-keeled, 3–4-nerved. Upper glume margins ciliate.

Florets
Basal sterile floret 1, without significant palea. Lemma of lower sterile floret oblong, 2.5 mm long, hyaline, 0-nerved, glabrous, ciliolate on margins. Fertile lemma linear, hyaline, 1-nerved. Lemma apex entire, 1-awned. Median (principal) awn geniculate, 10–25 mm long overall, with a twisted column. Column glabrous. Palea absent or minute. Anthers 1.2–1.5 mm long. Grain 2 mm long.

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

Australian Distribution:
Western Australia, Northern Territory, South Australia, Queensland, New South Wales.

Western Australia: Gardner, Fitzgerald, Hall, Dampier, Canning, Fortescue. Northern Territory: Darwin & Gulf, Victoria River, Barkly Tableland, Central Australia North, Central Australia South. South Australia: Flinders Ranges. Queensland: Cook, Burke, North Kennedy, South Kennedy, Port Curtis, Leichhardt, Burnett, Wide Bay, Darling Downs, Moreton, Mitchell, Warrego, Maranoa. New South Wales: North Coast, Northern Tablelands, North-Western Slopes, Central-Western Slopes, North-Western Plains.

Classification. (GPWG 2001):
Panicoideae: Andropogoneae

Notes
There are two subspecies:

Sessile spikelets c. 4 mm long, not or vary rarely pitted	B. bladhii subsp. bladhii (NSW NT SA WA QLD) B. intermedia
Sessile spikelets c. 3.5 mm long, sessile or pedicelled spikelet always pitted	*B. bladhii subsp. glabra (NSW QLD) B. glabra

Bothriochloa bladhii (Retz.) S.T.Blake subsp. bladhii
Native. An important and widespread forage grass of Eucalyptus forests and woodlands of the Australian tropics and subtropics, particularly on heavy soils.
Found in all mainland states except Vic; possibly naturalised in S.A. Extends through New Guinea and SE Asia to India. Flowers Oct.–Aug.

Bothriochloa bladhii (Retz.) S.T.Blake subsp. glabra (Roxb.) B.K.Simon
Introduced. Naturalised in a few localities of Qld and N.S.W. Tropical Africa to Taiwan. Flowers Apr.

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