What Types of Weeds Look Like Grass?

Maintaining a flawless, vibrant golf course lawn is a top priority for many of us. However, the battle against weeds that look like grass can be a relentless one. These deceptive intruders not only jeopardize the aesthetic appeal of the lawn but can become invasive, competing with the grasses you want to keep in your lawn.

In this comprehensive guide, we will delve into the world of grass-like weeds commonly found in lawns. We will explore their distinct appearances, growth sizes, and control methods so that you can ensure your lawn remains a haven of lush, immaculate grass.

Identifying Grass-like Weeds on Your Lawn

Identifying grass-like weeds is essential for implementing appropriate control measures. While these weeds may bear resemblances to desirable turfgrasses, there are key characteristics that can help differentiate them. Understanding their appearances and distinguishing features will help you accurately identify and eliminate these weeds.

Crabgrass (Digitaria sanguinalis)

Crabgrass is one of the most common and persistent grass-like weeds found on lawns. This warm-season annual weed spreads horizontally across the turf and forms dense patches. Its appearance and growth can make it particularly challenging to control. 

If you come across crabgrass growing in sidewalk cracks or areas without other desirable grass, you have a couple of options for removal. You can pull it out by hand or use a non-selective herbicide for spot treatment.

For effective control of crabgrass in cool and warm-season lawns, we recommend using pre-emergent and post-emergent herbicides. Tenacity is ideal for cool-season and Centipede lawns because it can prevent growth and eliminates mature plants, all-in-one. The best part is that Tenacity specifically targets over 45 broadleaf weed species without harming your grass. Its versatility allows for application during seeding, including overseeding of established turfgrass, renovation projects, or bare ground seeding.

On warm-season lawns, a great choice is Celsius® WG, a broadleaf and grassy weed killer that does a great job controlling weeds while minimizing damage to your lawn. Mature crabgrass may take more than one Celsius application to control. Quinclorac also works well when temperatures are below 85 degrees.

Once the crabgrass is under control, do your best to get your lawn in great shape. Like most weeds,  crabgrass thrives in poorly maintained lawns.  

Appearance	Crabgrass typically has light green, coarse-textured leaves that radiate from a central point. The leaves are broader than desirable turfgrasses and may have a slightly bluish tint. As the weed matures, it produces finger-like seed heads that can rise above the turf canopy, giving it a distinct appearance.
Growth height	Typically grows to a height range of four inches.
Looks like	Bermuda grass, Kentucky bluegrass.
Weed control tip	Mulching  Hand-pulling young plants Tenacity, a post and pre-emergent herbicide on cool-season lawns Celsius® WG combined with surfactant on warm-season lawns. Quinclorac when temperatures are below 85 degrees.

 

Annual bluegrass (Poa annua)

Annual bluegrass is another grass-like weed that commonly infiltrates lawns. Despite its name, annual bluegrass can act as both an annual and a perennial, depending on environmental conditions. This weed is all about cool and moist climates, and it loves hanging out in the shady spots of your lawn, especially under big trees.

It's related to Kentucky bluegrass but has a lighter and brighter shade of green. You can spot it by looking for that long membrane that attaches the base of the leaf to the stem.

To tackle it, the best move is to deny it the conditions it craves, so try to avoid creating shaded and moist areas where it thrives. If you spot some of it growing, you can hit it with herbicides. An ounce of prevention is worth a pound of cure when it comes to Poa annua. Pre-emergent herbicides are a great way to keep this weed out of your lawn.

If you have a warm-season lawn such as Bermuda, Zoysia, or St. Augustine, Certainty herbicide which is included in our Celsius and Certainty Herbicide Kit will do a great job controlling annual bluegrass (and many other grass-like weeds). Around two weeks after application, the weeds should begin to yellow, eventually dying off. 

For cool-season grass, go with Velocity PM herbicide to selectively control Poa annua.

Appearance	Annual bluegrass has fine-textured, light green leaves that form dense tufts or patches in the turf. Its leaves are typically narrow and boat-shaped, distinguishing it from desirable grass species. During its reproductive stage, it produces seed heads with small white flowers that give it a distinctive appearance.
Growth height	Generally grows to a height range of between four and eight inches.
Looks like	Kentucky bluegrass.
Weed control tip	Use pre and post-emergent herbicides. Warm-season lawns: Certainty herbicide with surfactant. Pre-emergent options include Prodiamine 65 WDG or Spectacle Flo. Cool-season lawns: Velocity PM herbicide for post-emergent control. Dithiopyr or Prodiamine pre-emergent herbicide such as Dimension or Prodiamine 65 WDG.

 

Carpetgrass (Axonopus)

Carpetgrass (sometimes known as Louisiana grass, flatgrass, or "petit gazon") is a warm-season grass well-adapted to humid and tropical regions. It thrives in areas with moderate to high moisture levels and can tolerate partial shade. It is also often added as a nurse grass in centipede seed mixes.

While it has some desirable attributes, such as its ability to withstand heavy foot traffic and grow in poor soils, carpetgrass is often considered a weed in lawns where it is not intentionally planted.

Carpetgrass loves moist soils, so if your lawn has high moisture in the area where these weeds congregate, improve drainage, aerate it, and see if the weeds die off naturally. Test your soil, too, as carpetgrass thrives in low-fertility, acidic soils. Your weed problem may be simply remedied with a lime application and fertilizer. Alternatively, you can use both post and pre-emergent herbicides to control carpetgrass, but remember to choose the “selective” type. Using a selective herbicide will prevent damage to your lawn as you target carpetgrass. 

Appearance	Carpetgrass has broad, coarse leaves with a dense, low-growing habit. Its leaf blades are typically light to medium green in color, and it forms a dense carpet-like growth pattern.
Growth height	Typically grows to a height range of between two and six inches.
Looks like	Centipede grass or St. Augustine grass.
Weed control tip	Test your soil and use fertilizer and lime to raise soil ph if your soil has low fertility and high acidity. Warm-season lawns: Celsius and Certainty Herbicide Kit  Cold-season lawns: Tenacity SedgeHammer Herbicide Kit

 

 

Related: What Are the 3 Most Common Lawn Weeds?

 

Common couch / Quackgrass (Elymus repens)

Common couch is a persistent and invasive grass-like weed that can quickly spread across lawns if left uncontrolled. Also referred to as quackgrass, it has strong rhizomatous roots that enable it to establish and multiply vigorously.

It prefers sparse and unhealthy lawns, so the key to keeping it at bay is ensuring your lawn is always in great shape. For cool-season lawns, you can try digging it up by hand or using a hand weeder tool. But you've got to make sure you pull out every single piece. If you leave anything behind in the soil, it'll just bounce back and start growing all over again. If you let it go unchecked, quackgrass can spread like wildfire across your lawn. So, it's important to tackle it as soon as you notice it.

Common couch (quackgrass) can be controlled in warm-season lawns using Certainty herbicide and surfactant. 

Appearance	Common couch has long, flat, and broad leaves that are often a shade of light green. The leaves have rough edges and a distinct midrib. It produces seed heads with spike-like structures that rise above the turf canopy.
Growth height	Typically grows to a height range of 12-30 inches.
Looks like	Bermuda grass.
Weed control tip	Warm-season lawns: Certainty herbicide and surfactant.  Cool-season lawns: Dig it out or spot spray with glyphosate, such as Roundup Quikpro (note that glyphosate is non-selective, so it will kill your lawn if the couch is not isolated before treatment).

 

 

Nutsedge (Cyperus esculentus)

Nutsedge is a grass-like weed that can be particularly troublesome on lawns. Also known as nutgrass, it is a perennial weed that spreads rapidly through underground tubers, or it can find its way in through airborne seeds, making it difficult to control. 

Nutsedges are weeds that you definitely don't want hanging around on your lawn. Once they settle in, they become incredibly stubborn to remove. This weed thrives in damp areas with poor drainage. Unfortunately, pulling them up won't do much good because they'll grow again from tiny fragments left behind in the soil. 

The smart move is to keep your lawn thriving and healthy so that it’s more difficult for these sedges to take hold. If they've already present, you’ll have to turn to herbicides to get rid of them. 

Appearance	Nutsedge has long, narrow, grass-like leaves that emerge in clusters from triangular stems. The leaves have a distinct midrib and a light green color. Nutsedge produces small, brownish seed heads that appear at the top of the stems.
Growth height	Typically grows to a height range of 8-24 inches.
Looks like	Bermuda grass, Kentucky grass.
Weed control tip	Prevention is easier than cure. Keep lawn well-maintained and manage drainage. Warm-season lawns: Certainty herbicide and surfactant.  Cool-season lawns:  SedgeHammer® is a great choice for sedge control.

 

Related: Identifying the Weeds That Could Destroy Your Lawn

 

Green foxtails (Setaria viridis)

Green and yellow foxtails are those pesky grass-like weeds that appear out of nowhere and start causing trouble for your beautiful lawn. They grow fast and can give tough competition to the desirable turfgrasses you want. So, you should have some solid management strategies up your sleeve to tackle them effectively. 

Foxtail isn't a big fan of cool and dry climates due to its weak roots, and it takes longer to sprout than it does to grow. In low light conditions, it grows slowly and stays relatively small. As it is an annual weed, you can uproot it or let it die naturally, then take steps to improve the health of your lawn to prevent it from coming back next season. 

Appearance	Green foxtails have narrow, cylindrical leaf blades that are light green. The leaves may be covered in fine hairs. The weed produces compact, bristled seed heads that resemble a fox's tail, giving it its name. Initially, the seed heads are green but turn yellowish-green as they mature.
Growth height	Typically grows to a height range of 12-36 inches.
Looks like	Kentucky bluegrass, Fine fescue.
Weed control tip	Mulching Warm-season lawns: Celsius herbicide and surfactant. Cool-season lawns: Tenacity herbicide and surfactant.  All grass types: Pre-emergent herbicides such as Prodamine 65 WDG.

 

 

Johnsongrass (Sorghum halepense)

Johnsongrass is a perennial grass-like weed that can be invasive and challenging to control. Native to the Mediterranean region, it has spread to various parts of the world, including North America.

It is relatively easy to get rid of by digging it up, but if you're dealing with larger patches, another natural option is to till the soil and let the rhizomes face the chilly winter temperatures. That frosty treatment will take care of them, but keep in mind that you'll need to reseed/sod the area the following year. It's a small trade-off for a natural approach to a weed-free lawn. 

Appearance	Johnsongrass has broad, lance-shaped leaves with a prominent midrib. The leaves may be hairy and have a bluish-green color. The weed produces tall, erect seed heads with clusters of grain-like seeds.
Growth height	Grows to a significant height, typically ranging from 24-72 inches.
Looks like	Tall fescue, prairie grass.
Weed control tip	Dig it up Warm-season lawns: Certainty herbicide and surfactant. Cool-season lawns: Acclaim herbicide and surfactant.  All grass types: Pre-emergent herbicides like Prodiamine 65 can tackle Johnsongrass seedlings.

 

 

Creeping bentgrass (Agrostis stolonifera)

Creeping bentgrass is a perennial grass-like weed, often deliberately planted, but you usually won't find it in regular yards. It's more commonly seen on golf courses, specifically on the fairways and putting greens. It is a cool-season grass that spreads through stolons, forming a dense and low-growing turf.  

Appearance	Creeping bentgrass has narrow, fine-textured leaves that are typically a vibrant green. The leaves grow densely and form a thick mat close to the ground. This grass-like weed produces inconspicuous seed heads that can be difficult to notice.
Growth height	Typically grows to a height range between two and four inches. Its low-growing habits and dense mat-like growth can impact the uniformity of your lawn.
Looks like	Fine Bermuda grass.
Weed control tip	Warm-season lawns: Celsius herbicide and surfactant. Cool-season lawns: Tenacity herbicide and surfactant.

 

 

Smooth bromegrass (Bromus inermis)

Smooth bromegrass is a perennial grass-like weed that, if left unchecked, can quickly take over your entire lawn. This is thanks to its dense root system and its knack for spreading through rhizomes. Once it sets its roots, getting rid of it becomes quite a challenge.

But if you keep your lawn well-maintained and show it some love, smooth bromegrass will struggle to compete with your desired turf grass. Mow it short and let the healthy grass crowd out the intruder. However, for more stubborn patches, there are effective herbicides out there that can come to your rescue.  

Appearance	Smooth bromegrass has broad, flat leaves that are typically bluish-green. The leaves may have a smooth texture, hence the name "smooth" bromegrass. The weed produces seed heads with clusters of spikelets that contain tiny seeds.
Growth height	Typically grows to a height range of 12-36 inches. Its ability to form dense clumps or patches can disrupt your lawn.
Looks like	Meadowbrome.
Weed control tip	Mow regularly, don’t let it grow tall  Use glyphosate herbicides, or for an organic alternative, try Mirimichi Green Organic Weed Control spray (this is a non-selective treatment, so you must isolate the weed to prevent your turf grass from damage).

 

 

Yellow salsify (Tragopogon dubuis)

Yellow salsify is a grass-like weed that often infiltrates lawns. Also referred to as western salsify or yellow goat's beard, it is a perennial plant with a deep taproot that allows it to establish and persist in various soil conditions. 

This weed enjoys full sunshine, but if you mulch your garden and keep your lawn healthy, it won’t have a chance to grow.  

Appearance	Yellow salsify features long, narrow leaves that are typically smooth-edged and covered in fine hairs. The leaves form a basal rosette close to the ground. As the plant matures, it produces tall flower stalks with vibrant yellow flowers resembling dandelions.
Growth height	Typically grows to a height range of 12-36 inches.
Looks like	Slender rush, some dandelion species.
Weed control tip	Mow regularly, don’t let it grow tall  Easy to pull up — make sure you take all the roots. Warm and Cool Season Lawns: Triad Select and surfactant.

 

 

Slender rush (Juncus tenuis)

Slender rush, or path rush, is a perennial weed that thrives in moist or wet areas, making it particularly challenging to control. Make sure you correctly identify this plant because using regular herbicides that work on grassy weeds won't do the trick. Even though sedges and rushes look a bit like grasses, they require different treatment methods altogether. 

Appearance	Slender rush has long, slender, round, vibrant green stems. The stems are smooth and leafless, with small clusters of tiny flowers at the tips. The leaves are reduced to sheaths that wrap around the stems.
Growth height	Typically grows to a height range of 12-36 inches.
Looks like	Sedges.
Weed control tip	Cultural control techniques are recommended for managing these plants. Hand pulling ensuring to get the roots. Following specified watering and mowing schedules can prevent establishment and spread. Mow lawn at shorter heights.

 

 

Goosegrass (Eleusine indica)

Goosegrass is a grass-like weed that commonly infests lawns. It is an annual weed that spreads rapidly through seed production and can quickly invade bare or thin areas of turf, especially where the soil is compacted and the sun shines bright.

Unfortunately, it can survive being mown closely and still produce seeds, so using herbicides is an option to kick it out of your lawn, but be warned, some strains have developed resistance to them. 

Goosegrass is best controlled by preventing it using a pre-emergent containing Prodiamine. If you have warm season grass, Specticle FLO is an excellent pre-emergent option.

Appearance	Goosegrass has wide, flattened leaf blades that are light green. The leaves have a distinct midrib and rough texture. The weed produces dense clusters of finger-like seed heads with small spikelets.
Growth height	Typically grows to a height range of 6-12 inches.
Looks like	Crabgrass.
Weed control tip	Cool-season lawns: Tenacity herbicide and surfactant. Zoysia lawns: Fusilade 2 Ensure good drainage in your soil Pre-emergent herbicides. Warm-season grass, Specticle FLO.

 

Related: How to Nail Weed Management This Summer

 

Preventing and Controlling Grass-like Weeds

Controlling grass-like weeds on lawns can be achieved through a combination of regular maintenance, herbicides, chemical control, and an integrated pest management (IPM) approach. By implementing these strategies, you can effectively manage weed infestations and maintain healthy, aesthetically pleasing turf.

Regular Maintenance Tips

• Mowing - Maintain the appropriate mowing height for your turfgrass species, ensuring that the grass remains at an optimal length. Regular mowing helps prevent weed seed production and encourages healthy turf growth, reducing opportunities for weed establishment.
• Watering - Practice proper irrigation techniques to avoid overwatering; this can promote weed growth. Water deeply and infrequently to encourage deep root growth in your turfgrass, making them more competitive against weeds.
• Fertilization - Apply fertilizers based on soil test results and the specific nutrient requirements of the turfgrass. Adequate fertilization helps maintain a dense, vigorous turf, limiting space and resources available for weed growth.
• Aeration - Regularly aerate the lawn to alleviate soil compaction and promote proper water and nutrient absorption. This supports healthy turf growth and helps prevent weed invasion.
• Overseeding - Overseed bare or thin areas with your cool-season turfgrass species to promote their growth and fill any spaces susceptible to weed encroachment.

Herbicides for Weed Control

• Pre-emergent Herbicides - Apply pre-emergent herbicides at the appropriate time to prevent weed seed germination. These herbicides create a barrier in the soil, inhibiting weed growth before it emerges. Spring pre-emergent should be applied before average soil temps reach 55 degrees. Fall pre-emergent works well when applied as soil temperatures reach 70 degrees trending cooler.
• Post-emergent Herbicides - Utilize post-emergent herbicides to target and control established weeds. Selective herbicides are specifically formulated to effectively target grass-like weeds while minimizing damage to desirable turfgrasses.
• Herbicide Application - Follow herbicide labels for proper application rates, timing, and safety precautions. Ensure even application and avoid overspray or drift to prevent damage to non-target plants.

Integrated Pest Management (IPM) Approach

• Monitoring - Regularly inspect the lawn for weed presence and identify areas prone to weed infestation. Early detection allows for timely intervention and prevents weed spread.
• Mechanical Control - Employ mechanical methods like hand-pulling, spot treatment, and mowing practices to remove isolated weed patches. This can be effective for small-scale infestations or sensitive areas where herbicide use is limited.

 

Related: What’s the Best Weed Killer Spray for Your Lawn?

 

Weed Out the Weeds

A proactive and multifaceted approach to weed control is key to maintaining the beauty and quality of golf course-like lawns. By implementing cultural practices, utilizing herbicides when necessary, and adopting an integrated pest management approach, you can successfully manage grass-like weeds, ensuring a well-maintained turf that enhances the enjoyment and experience of your lawn.

Browse our full range of weed killers and find one which works for your lawn.