Originally published May 7, 2012
To the right is a picture of yellow nutsedge exhibiting two characteristics that contribute to its ability to be a serious pest. The “nut” part of its common name is derived from the structure shown at lower left. It is not a nut, but is actually a tuber, an enlarged part of the rhizome. The white, root-like structures are also rhizomes which are underground stems. If the stems were above ground they would be called stolons. These structures are underground and well protected from herbicide sprays. To really get to them requires a good translocated herbicide. If you plow and cut the tuber off from the main plant it just produces a new plant from the tuber. The plant can also produce lots of viable seed enabling it to survive by more than one method. One way to distinguish yellow nutsedge from purple nutsedge is to cut the tuber and smell it. If it has a petroleum odor it is purple nutsedge. Purple nutsedge also has a more blunt leaf tip than yellow nutsedge. The tubers of purple nutsedge are hairy compared to the fairly smooth yellow nutsedge tubers. Yellow nutsedge is actually sold as Chufa to be used in wildlife food plots. Apparently turkey will scratch up the tubers and eat them. One biologist said he found the crop of Teal killed in a rice field full of the tubers. If they would leave the rice seeds alone and selectively consume the tubers it sure would help.
Yellow nutsedge with tuber
The LSU AgCenter and the LSU College of Agriculture