Yellow nutsedge is one of the most despised weeds of our flower and vegetable gardens. Eradicating it from your property is almost impossible. Pull it all out and more plants show up within days.
Most people refer to it as a grass, but its stems are triangular in cross-section, which makes it a sedge. It appears in mid-spring and lasts until fall. Plants can grow up to three feet tall if left alone. Nutsedge is extremely tolerant of prolonged wetness, so it survives where other plants won’t.
Seed heads emerge in summer. Light tan to golden brown seed heads are surrounded by a ring of leaf-like structures called bracts. Seeds can spread to form new plants, but that’s not what makes this plant so prolific.
A series of underground stems called rhizomes intermingle with the roots. At the end of each rhizome is a tuber, often called a nutlet. A tuber is a swollen stem for food storage and reproduction. Potatoes reproduce by tubers. A single nutsedge plant may produce several thousand tubers per year. They are a little larger than garden peas.
These nutlike structures remain underground when plants are pulled from the garden. New plants spring up shortly afterwards. Individual tubers contain many buds and can sprout several times before exhausting their energy.
This grass-like weed is common in almost every state as well as many of the Canadian provinces and much of Mexico. Nutsedge isn’t controlled well by most herbicides. Often when plants are sprayed, the nutlets fall off and aren’t affected by the chemical. That’s one reason they are difficult to control. Consequently, numerous chemicals have been developed specifically to control this weed. It’s tough and vilified.
Thirty-six years ago I studied this species in my plant taxonomy class. I remember its scientific name was Cyperus esculentus. In Latin, esculentus means edible, but few farmers or gardeners ever consider eating it.
The tubers are quite good. When dried and roasted they have a somewhat sweet flavor, almost like hazelnuts. I’ve even heard them referred to as earth almonds. Native Americans used nutsedge as food and medicine. They consumed the seeds as well as tubers.
Those familiar with chufa might recognize the flavor. It’s a common food in much of Africa among other places and has been for centuries. According to records, Egyptians consumed it over 4000 years ago.
Tubers are high in Omega-3 fatty acids and make high quality oil similar to olive oil. Chufa and nutsedge are variants of the same species. The only difference is that chufa is less winter hardy. Chufa tubers are also a little larger.
If you want to collect some nutsedge tubers to try, you’ll have no trouble finding some. Obviously, collect from an area not treated with herbicides. Also, remember that they are small. You’ll have to gather a bunch. If ridding the area of them is your goal, you still won’t get them all. Additionally, cleaning them up in all but the sandiest soils can be quite a pain.
Ted Manzer teaches agriculture at Northeastern High School.