Cyperus esculentus - Yellow nutsedge

Description

Herbaceous, up to 80 cm tall, with slender, soft, pale perpendicular, scaly rhizomes producing brown to darkbrown tubers. Tubers are more or less globose, usually soft, with rings around the tuber.

Stems

Erect, glabrous, smooth, three-angled.

Leaves

Grasslike, up to 30 cm long and 12 mm wide, expanded, glabrous, smooth and shiny. Forms from the base of the plant.

Inflorescence

A compound or simple umbel, bracteate; bracts three to five, similar to leaves, as long or longer than the umbel.

Spikelets

Up to 2 cm long, 8-14 flowered straw-coloured or often yellow, compressed; glumes ovate.

Distribution

Widely distributed throughout South Africa

Notes

Susceptible to acetanalides, bendioxide and thiocarbamates. Difficult to control and is very competitive.

Allelopathic references

DROST, D.C. & DOLL, J.D., 1980. The allelopathic effect of yellow nutsedge (Cyperus esculentus) on corn (Zea mays) and soybean (Glycine max). Weed Science 28, 229-233.

RICE, E.L., 1995. Allelopathy in forestry. In: E.L. Rice (ed.). Biological control of weeds and plant diseases: Advances in applied allelopathy. University of Oklahoma Press. Norman. 317-378.

TAMES, R.S., GETSO, M.D.V. & VIEITEZ, E., 1973. Growth substances isolated from tubers of Cyperus esculentus var aureus. Physiology of Plants 28, 195-200.