Panicum maximum var. trichoglume
green panic
Strong, light green perennial tufts to 120 cm, from very short rhizomes, with open fans of ascending to erect culms. Leaf-sheath firmly chartaceous, folded, keeled and ribbed, softly villous above, with longer tubercle-based hairs near margin. Collar hairs long, tubercle-based. Ligule c. 1 mm. Leaf-blade c. 25 cm × 5-8 mm, flat, linear, finely, minutely pubescent, abaxially strongly keeled, adaxially with central furrow; margins finely, closely scabrid, tapered in upper ⅓ to long fine tip. Culm to 100 cm, flattened below, with wide shallow furrow on one side. Panicle 15-25 cm, ± erect, very open, with spikelets borne towards tips of long, filiform to capillary branches. Spikelets c. 3 mm, elliptic-oblong, somewhat turgid, minutely pubescent, purplish. Glumes faintly nerved, thin; lower c. 1 mm, ⅓ length of spikelet, rounded, obtuse, hyaline, 1-nerved, upper = spikelet, elliptic, obtuse, 5-nerved. Lower floret ♂: lemma ≤ 3 mm, 5-nerved; palea slightly shorter; anthers 1.5-2 mm. Upper floret ⚥: lemma ≥ 2 mm, elliptic-oblong, shortly acute, finely transversely rugulose; anthers 1-1.4 mm; caryopsis not seen.
N.: Auckland City (Ellerslie). On motorway berm.
Naturalised from Africa.
P. maximum var. trichoglume was first collected from a single clump in 1979 by A. E. Esler 6007 (CHR 357511). In spite of annual herbicide treatments, plants had spread along the edge of the motorway for more than 100 m by 1986.
Webster, R. D. Australian Paniceae 241 (1987) transferred P. maximum to Urochloa because of the rugulose lemma of the upper floret.
