nutgrass

Family

Cyperaceae

Scientific Name

Cyperus rotundus

Other Common Names:

chaguan humatag

cocograss

pakopako

kili'o'opu

purple nutsedge

Habit

Nutgrass is a perennial weed plant from rhizomes and tubers. It can reach 2 1/2 feet in height. It is found throughout the southeastern United States as a common weed of agronomic and horticultural crops, nurseries, turfgrass, and landscapes.

Leaves

The leaves are yellow to green in color with a distinct shiny appearance. Leaves are 5mm to 8 mm wide. They have a distinct ridge along the mid-vein. Leaves are without hairs and appear triangular in appearance. No auricles or ligules are present in Purple Nutsedge. The leaves of purple nutsedge taper abruptly to a very sharp point unlike those of yellow nutsedge which taper gradually to a point.

Identifying Characteristics

The success from this troublesome weed is due to its ability to survive and reproduce from tubers during adverse conditions. It grows in almost every soil type, over a wide range of soil moisture, pH and elevation. It can survive the highest temperatures encountered in agriculture.

Flower Seed Head

Purple Nutsedge spikelets occur at the ends of the solitary stems where the flower stalks arise from a common point. Individual spikelets are reddish-purple to reddish-brown in color.

Seed Fruit

Seed is linear to oblong about 1.5 mm long and 1 mm wide. It has a triangular cross section and is olive gray to black and has gray lines on it. Plant most often grows back from tubers.