Jeffrey Beasley, Sanders, Kayla, Strahan, Ronald E., Voitier, Matthew | 5/10/2018 1:41:57 PM
Purple nutsedge (Cyperus rotundus L.) is a perennial weed common throughout Louisiana. Its leaves somewhat resemble a grass. However, it is actually a member of the sedge family. Its flowers produce few viable seeds, but it spreads primarily through underground tubers connected by rhizomes (underground stems). These tubers can form underground chains, allowing purple nutsedge to establish rapidly. Purple nutsedge has darker green leaves with rounded leaf tips and is generally shorter in height compared to yellow nutsedge, which has lighter green leaves with pointed leaf tips and is generally taller. Also, purple nutsedge produces tubers in connected chains.
Purple nutsedge can be identified by its shiny, green, grass-like leaves that are rounded at the tip. All sedges have triangular stems. The flower has multiple stalks that are purple to reddish-brown in color. Purple nutsedge produces small, brown tubers that are connected by rhizomes (underground stems) to form underground chains.
For more information on Purple nutsedge identification and characterization visit the USDA Plants Database at https://plants.usda.gov.
The best way to prevent or reduce weed encroachment is to maintain a healthy lawn through regular mowing and proper fertilization and soil pH management. Properly maintaining a lawn through these cultural practices promotes dense and vigorous turfgrass, which allows the grass to better compete with weeds. Below are the recommended mowing and nitrogen fertility rates recommended for each turfgrass species. In addition to these lawn care practices, manual removal of weeds may also be necessary. Physically removing purple nutsedge is difficult because of the chain of rhizomes. Increasing drainage can help reduce purple nutsedge occurrence.
In addition to cultural practices, herbicide applications may be required to achieve effective weed control. Several post-emergence herbicides control purple nutsedge in lawns. However, no single application will provide season-long control. When using any herbicide, always follow the manufacturer's labeled directions.
For more information regarding pesticides for turfgrass please reference the Louisiana Suggested Chemical Weed Control Guide.
For information regarding weed identification and control options please contact your local LSU AgCenter Extension Parish Office. To find your local LSU AgCenter Extension Parish Office visit here.