What Is Cyperus Rotundus?

Where It Grows

• Temperate and tropical climates support the purple nutsedge worldwide. In the United States, this terrible weed is mainly a fixture in Southern states, where it invades flower and vegetable gardens as well as large crop fields. It will grow in waste places, along the side of a road, in pastures and in fields. No temperature is too great to prevent its development and spread.

Description

• The mature specimen of Cyperus rotundus is erect, grows to 30 inches and lacks any hairs on its stems or leaves. It looks glossy and is similar in appearance to most types of grasses, but is thicker and has a stiffer texture. The flowering stems are three-sided, looking triangular when put in cross-section. Leaves are dark shades of green and less than 1/4 inch wide. The species gets its name from its tiny spikes of purple-brown flowers.

Reproduction

• In the United States, purple nutsedge usually fails to produce seeds. It does not have to, as the plant multiplies by producing underground roots known as rhizomes. Growing in the upper 12 inches of soil, they spread out horizontally from the plant, with new tubers developing from them and generating viable, new plants. Once the weed establishes itself in an area, it is extremely difficult to eradicate or control.

Effects

• By using up available resources, purple nutsedge robs nearby plants of water and nutrients, thereby drastically affecting them. In crop fields, purple nutsedge reduces production significantly, especially among such staples as corn, cotton, sugar cane and tomatoes. Its ability to spread rapidly makes up for its smaller size. It takes the place of native species that wildlife depends on for food and shelter.