Nutsedge - the weed most likely to drive a homeowner or lawn care professionals nuts...no pun intended!
Nutsedge, Cyperus esculentus L., also called nutgrass, is an aggressive perennial weed that is native to North America and Eurasia. It is a problem weed in lawns, landscapes and gardens across North America. The sooner you get control of this invasive weed the better!
Identifying Nutsedge
You'll usually find nutsedge in areas of the landscape where it thrives, which is low, damp soils. The amount of rainfall determines the amount of nutsedge. The more rain the more nutsedge. Nutsedge is most noticeable in ditches or any place where water stands frequently. Unfortunately, It can show up in your lawn, landscape and flowerbeds sometime about mid spring, persisting and spreading throughout the growing season.
Yellow nutsedge, a monocot and member of the sedge family, and the most common type in North America, is frequently mistaken for lawn grasses because of its narrow, grass-like leaves. I think it looks similar to Liriope, or what some call "lilyturf" or "monkeygrass." Nutsedge is a paler green than most lawn grasses. What distinguishes it most from lawn grasses is its triangular (three-ranked) solid stem, which is free of nodes. Too, in the lawn, nutsedge grows so quickly that one or two days after you mow, it’s up higher than your lawn. The shiny v-shaped leaves, flower stalk, roots, and rhizomes of this plant originate from a bulb located just beneath the surface of the ground. Yellow nutsedge has an extensive underground system of rhizomes and tubers (or nutlets) that store large reserves of energy. This system allows the plant to overwinter and produce new shoots the following spring. Brownish to rust-colored oval nutlets, measuring 1/4 to 1/2 inch in diameter form on the ends of the rhizomes in the upper 6 inches of the soil.
One Nutsedge plant can produce several hundred to several thousand bulbs during a single growing season. Too, if allowed to grow to maturity, each plant can produce a cluster of straw-colored seed heads. The clusters, which resemble bottle brushes, form at the top of the central stalk about two months after the plant emerged. Mature yellow nutsedge can produce hundreds of millions of seeds per acre. However, the viability of a mature seed is relatively low, ranging from 5 to 40 percent. Seed germination and seedling survival are highly dependent on favorable environmental conditions, and seedlings often perish due to their small size and lack of vigor. Still, that being said, it's very important to quickly identify Nutsedge so that you can take steps for eradication before it gets out of control.
Two other nutsedge species, purple nutsedge and chufa, do not grow in cooler regions of the world. Purple nutsedge (Cyperus rotundus L.) is a weedy species found mostly in the southeastern and southwestern parts of the United States. Chufa (Cyperus esculentus, var. sativus), which is a less aggressive variety of yellow nutsedge, is grown as a food crop in southwestern Europe, Africa, and parts of Asia. Processed nutlets of the chufa plant are used in a variety of foods, beverages, and soaps.
How To Kill Nutsedge
Good news is, despite its widespread presence, nutsedge can be effectively eradicated.
Lawns
Hand pulling or digging up the tubers and "nuts" is usually not an option in lawns. When attempting to pull the weed out of the ground the blades of nutsedge usually snap off leaving the tubers beneath the soil surface to spread and grow more plants. You can dig the plants and tubers up in lawn areas however this leaves you with bare spots and holes to fill. If you miss some of the tubers plants will quickly grow back.
Herbicides are the most effective way to eradicate nutsedge in lawns. There are several products on the market that are quite effective. I use one called Hi-Yield Nutsedge Control, however any product containing halosulfuron will control nutsedge. These are best used when the plant is young and are more effective, and when a nonionic surfactant is added such as High Yield Spreader Sticker. Whenever using a chemical, always closely follow instructions for mixing rates and application found on the product label.
Landscape Beds
Controlling nutsedge in landscape beds is a little easier. Small plants just an inch or two high can be pulled by hand. Larger clumps can be dug. You can also use a glyphosate-based product to spray and kill the nutsedge. Roundup is one such product, however there are now much cheaper alternatives. I use Hi-Yield Killzall which is a 41% glyphosate super-concentrate.
Be very careful when spraying glyphosate as it will kill almost any type of plant you spray it on. If you're spraying to kill nutsedge or other types of weeds around shrubs or trees do so on a calm day and adjust your sprayer nozzle so that it sprays more of a stream than a fog. Do not attempt to kill nutsedge or any other types of weeds growing in your lawn with glyphosate as you'll most likely kill your grass!
Flowerbeds & Vegetable Gardens
In flowerbeds and vegetable gardens I usually stick to the hand pulling method. Annual bedding plants are usually spaced too close together to risk accidentally spraying them with an herbicide. The soil in flowerbeds is usually much softer and it's easier to pull the plant and its roots from the ground. Plants in the vegetable garden may be spaced a little further however I don't like spraying any toxic chemical around veggie plants that will end up on the dinner table. So, for me, pulling by hand or digging the plants is the best way to remove them from the garden.