Gynerium sagittatum P.Beauv.

Very coarse, tall, leafy, perennial reed; culms as much as 15 m. high, with short internodes; sheaths much longer than the internodes, with a long densely villous patch on the back below the blade, also villous in the throat and on the margins near the summit, reticulate-veined, the lower ones soon falling off; blades sharply serrate, commonly 2 m. long, 4-6 cm. wide, forming a great fan-shaped summit to the sterile culms; panicles 1 m. or more long, erect, the branches drooping; pistillate spikelets: glumes very unequal, the first about 4 mm. long, the second 10-12 mm. long; body of lemma about 2 mm. long, tapering gradually into a soft delicate awn 3-4 mm. long, the hairs on the lemma exceeding the awns; staminate spikelets: glumes acute or subacuminate, the first 2-3 mm. long, the second a little broader, about 3 mm. long; lemmas 3 mm. long, acuminate, glabrous.

It is a subtropical plant. It is best in light shade. It needs a pH between 6-8.5. It cannot tolerate frost. In Argentina it grows from sea level to 1,700 m above sea level.

It can be grown by seeds or cuttings. A spacing of up to 90 cm is suitable.