CRABGRASS OR NUTSEDGE?
by Chris Gurreri
You may have noticed that your water-starved lawns are slowly starting to recover from the drought, but another problem is lurking outside in the form of many bright green patches. Your first thought is to blame it on that pesky crabgrass that we try to block every spring. However, at a closer glance, you’ll notice a distinct difference in appearance, which indicates that you have one of the most invasive weeds in your lawn, Nutsedge.
Nutsedge is a species of sedge that, at first, will resemble normal grass, but has a distinctive shape to its leaves. You can differentiate Nutsedge from crabgrass and regular turf grass by cutting a cross-section of the leaf or stem. If it is Nutsedge you will notice an obvious triangular shape.
Not only is Nutsedge extremely invasive to your lawn, but it’s very difficult to control. The name ‘Nutsedge’ itself is derived from its tubers (which is how it reproduces) just like many perennials. It’s because of these tubers in the soil that the Nutsedge can continue to thrive year after year, even if you’ve treated for it. Most herbicides are ineffective in treating Nutsedge, and the ones that are only kill the leaves you see in your lawn, not the root system or tubers.
You’ll also notice that Nutsedge tends to grow in the areas of your lawn that retain the most moisture and/or have the thinnest turf density. The most effective chemicals to treat Nutsedge are not usually sold to home gardeners. However, proactive measures can be taken to help healthy turf grass “choke out” the presence of these weeds.
Core aerating and overseeding your lawn in the fall are great ways to fight back in the war against weeds, especially on newer lawns that have recently been established. Creating a dense, thick lawn will help your healthy grass overtake difficult weeds like Nutsedge and crabgrass. Also, be sure to cut your lawn at a height no less than 2 ½ to 3 inches, as cutting it shorter will reduce the turf’s root system and its ability to compete with weeds like Nutsedge.
If you’re seeing a great deal of bright green patches in your lawn, take a moment to pull a sample and compare to this article. If you do have Nutsedge it’s not the end of the world, but taking action sooner rather than later will increase your chance to eradicate the problem. If left untreated, Nutsedge will continue to thrive and spread each summer, and become an unsightly inhabitant of your lawn!