It is hard to maintain a lush and uniform lawn that stays green throughout the year. Many external factors creep in and can cause chaos on an unsuspecting lawn. Sometimes when we are reseeding a lawn these weeds that look like wheat might cause problems. Or sometimes you want to make your lawn even richer. You might even add white clover to naturally fertilize your lawn. But even that could expose your yard to lawn weeds that look like clover. Fortunately, you can easily tell these common weeds from the grass on your lawn. But what happens when the weeds destroying your lawn are weeds that look like grass?
Most Common Weeds That Look Like Grass
I have found 17 lawn weeds that look like grass. Annual bluegrass, crabgrass, quackgrass, carpetgrass, goosegrass, bentgrass, johnsongrass, smooth bromegrass, and alexandergrass might sound like turf you’d want on your lawn but that is not the case. Nutsedge, broom sedge, blue fescue, foxtail, slender rush, wild onion and garlic, dandelion, and yellow salsify can also masquerade as a grass until the damage is done. To stop these lawn weeds that look like grass, we need to take a closer look at these imposters.
A Closer Look at Lawn Weeds that Look Like Grass
Lawn weeds that look like grass can be harmful to your turf and cause dry patches or leave lawns exposed to pests and diseases. The best way to keep a lush green lawn is to know what grasses are turf and which ones are weeds. Find out what to do when these 17 lawn weeds that look like grass invade by learning about each one.
1. Annual Bluegrass (Poa annua)
What It Does
This invasive grass creeps into moist, cool lawns. During the spring and wetter seasons, it gets a hold but when the dry summer heat hits it, annual bluegrass dies off leaving ugly blotches on your poor lawn. You can quickly remove the bluegrass when it dries up but then you will be left with a bare spot you need to reseed.
What It Looks Like
It is best to identify annual bluegrass before it spreads. You can recognize this lawn weed that looks like grass by its long ligule or membrane which attaches the leaf to the stem. Annual bluegrass is also a brighter and lighter green than other bluegrasses used for turf. Once you have identified this weed you can get rid of it.
How to Get Rid of It
Since annual bluegrass prefers cool and damp lawns you can easily cause it to die off by letting your lawn dry out. Once the bluegrass has started to brown you can easily remove it and resow or resod accordingly. If possible, try to do this before the summer to avoid stressing the rest of your lawn. If you found it late in the summer pre-emergent herbicides such as dithiopyr, bensulide, and oryzalin can be applied to stop bluegrass from returning in the spring.
2. Crabgrass (Digitaria sanguinalis)
What It Does
Crabgrass can affect hot humid lawns and pops up in large patches. Unlike some of the other lawn weeds that look like grass, crabgrass is not an indicator of an unhealthy lawn. This weed thrives in lush moist turf and can be a real problem. It tends to die off when temperatures drop and can leave bare spots on your lawn that you will need to attend to next spring.
What It Looks Like
Fortunately, it is very easy to tell crabgrass from your preferred turf. This grass weed is much courser than other grasses and grows in a crab shape out to either side instead of straight up. It grows quicker than the surrounding turf so you will notice it as it tries to smother your lawn.
How to Get Rid of It
Crabgrass is an annual and will not make it through the winter to spring. However, it can still do tremendous damage and needs to be eradicated immediately. The best way to kill crabgrass is to dilute vinegar to 5% acidity and then spray 3 times a week through till spring. Once you have established a strong lawn canopy, crabgrass will no longer be able to germinate.
3. Quackgrass (Elmys Repens)
What It Does
This lawn weed that looks like grass grows quickly in thin lawns and thrives in full sunlight. It prefers cooler climates but can spread very quickly through a lawn. It can spread by rhizomes underground as well as with seeds by air. Once it is established it is nearly impossible to manually remove.
What It Looks Like
Also known as common couch, this lawn weed is easy to identify by its fingerlike growth. It produces multiple blades off of a thick stem and can sprout up anywhere the lawn is thin. It produces mat-like growth and spreads over surrounding turf choking it out. The leaves are light green and the patches appear an ashy blue-green color.
How to Get Rid of It
The best way to control quackgrass is to prevent it from sprouting. As long as there are no thin areas of turf in full sun you should be able to avoid this grass taking over. However, if you have an infestation of common couch you will need to take serious action. You can use a non-specific herbicide but will likely harm the turf surrounding it. Alternatively, you can pull up the lawn weed and cover it with black plastic throughout the summer. This will kill the rhizomes and seeds and protect your lawn. When spring comes around be sure to thicken these areas of turf to prevent any regrowth.
4. Carpet Grass (Axonopus sp.)
What It Does
This lawn weed that looks like grass is most likely to appear in a humid climate where poor drainage has led to a boggy area. These boggy areas tend to be acidic and these conditions cause carpetgrass to take off. This weed grass grows quickly reaching 12 inches by summer. It spreads out and as the name implies carpets your turf killing it and taking its place.
What It Looks Like
You can easily identify carpetgrass by its crinkly leaves. The weed has a waxy and shiny appearance and is bright green. There may be some red and purple along the base of the stem. In the summer, carpetgrass turns brown and shoots up a seedhead.
How to Get Rid of It
There are a few ecological methods to removing carpetgrass without resorting to harmful chemicals. Dissolving ¼ cup of salt in a gallon of water and dousing the lawn weed should be enough to kill it. If it is still alive after that you can let it dry out. The last resort would be broad leaf herbicides.
5. Goosegrass (Eleusine indica)
What It Does
This lawn weed will grow in large clumps wherever there is poorly drained and compacted soil. It can branch out like crabgrass and reaches 16 inches high. It will quickly smother out all of the turf that is struggling from reduced aeration and can affect a large area. As an annual, it will die out at the end of the year leaving unsightly gaps throughout your lawn.
What It Looks Like
Although goosegrass resembles crabgrass it is not related. It gets its name from the seed heads that grow and spread out like a goose’s foot. To identify this lawn weed that looks like grass before it bolts, look for light green grass growing in large clumps with long, flat stems. Once you’ve identified this weed grass you will need to get rid of it.
How to Get Rid of It
It is possible to prevent goosegrass from ever getting established if you keep your lawn well fed and aerated. Applying corn meal gluten in the spring can also act as a pre-emergent. If you have a clump already you can manually remove it. Herbicides such as mesotrione and dithiopyr can be used in an emergency.
6. Bentgrass (Agrostis palustris)
What It Does
This grass weed prefers cool weather and can grow quickly in the spring outpacing slower-growing turf grasses. Once the temperatures rise in the summer this grass turns brown and leaves your lawns exposed in large areas.
What It Looks Like
Bentgrass can be identified by its blue-green patches and quick puffy growth. It is a lighter green than other grasses and is most commonly seen as the green of a golf course. So while this plant is tolerated more than other weeds that look like grass it still isn’t wanted on most lawns.
How to Get Rid of It
This grass weed is very easy to spot early in the spring and can quickly be removed by hand. When pulling make sure to remove the entire root so it doesn’t continue to spread. If you have a large patch you can use an herbicide such as mesotrione.
7. Johnsongrass (Sorghum halepense)
What It Does
This fast-growing grass weed can reach a height of 7 feet and has leaves that are up to 2 inches wide. It can quickly spread seed by wind or divide by rhizomes. Johnsongrass can very quickly crowd out a thin area of lawn and once it is established can be difficult to completely remove.
What It Looks Like
In addition to being a fast-growing tall grass, you can recognize this weed by its bright green color and the noticeable white line running along the center. Purple flowers can be seen on this weed from when they emerge in spring till when they die off in the fall.
How to Get Rid of It
There are several ways to remove this lawn weed that looks like grass. The least destructive is to remove the weeds by hand and pour vinegar where the roots were. If the area is too large to hand pull you can til when the weather cools in the fall. The colder temperatures will kill the rhizomes and prevent them from spreading. Finally, you can use sulfosulfuron, a herbicide that doesn’t harm most turf grasses but effectively destroys johnsongrass.
8. Smooth Bromegrass (Bromus ramosus ramosus)
What It Does
This weed that looks like grass grows quickly and spreads underground via rhizomes. Once established, the perennial smooth bromegrass is very hard to completely get rid of. It can quickly take over and choke out a thin lawn and can survive cold temperatures. It is important to identify this grass weed quickly to prevent turf damage.
What It Looks Like
This weed grows similar to other grass weeds and resembles hay as it grows. It can reach 2 to 4 feet and puts up purplish flowers. The leaves can grow to be 4 to 10 inches. On the leaves, you can see a short “w” near the tip.
How to Get Rid of It
The best way to remove smooth bromegrass is by mowing it low and then surrounding it with rich lush turf. Once your lawn is reestablished it will be easy to keep this grass weed under control. To weaken it further you can apply herbicides that are gentle for your existing turf.
9. Alexander Grass (Brachiaria plantaginea)
What It Does
Another lawn weed that looks like grass is alexandergrass. This is a warm-season annual that creeps into a thin turf and takes root. When the cooler season comes it browns and dies off.
What It Looks Like
Alexandergrass has a smooth stem and roots at the nodes. It creeps low and can sprout up to 18 inches tall. Leaf heads are smooth and it has a darker green color.
How to Get Rid of It
Since this lawn weed that looks like grass is an annual it will naturally die off at the end of the year. Once it has died off you can resod and add some pre-emergence herbicide.
10. Nutsedge (Cyperus sp.)
What It Does
This weed that looks like grass will invade an overwatered lawn. It grows little nutlets in the root. Nutsedge spreads by seed and rhizome and can quickly take over a boggy lawn.
What It Looks Like
This is a fast-growing grass that is either yellow or purple. It comes up quickly and will out-grow the turf between cuts. Nutsedge can be dug up in clumps to reveal the nutlets.
How to Get Rid of It
To avoid spreading the lawn weed further do not pull it or dig it up. If you do this you will break off portions of the rhizome which will quickly propagate. You can let the lawn dry out and choke out nutsedge with thick turf. If you need it gone fast you can apply nutsedge-specific herbicides directly to the plant.
11. Broom Sedge (Andropogon virginicus)
What It Does
This stubborn, sun-loving lawn weed grows quickly and in large bunches. If areas of your lawn have low fertility and low pH then there is a good chance this lawn weed that looks like grass will appear.
What It Looks Like
During the summer Broom Sedge is medium green and looks like an overactive area of lawn. As summer turns to fall, the leaves change to orange with a copper tint. It puts up seed heads that look like broom bristles.
How to Get Rid of It
Manual removal of broom sedge is effective and can help reduce the chance of regrowth the following year. As it is a true grass and not a sedge as the name implies, any plant-specific herbicides will harm the turf grass. Adding lime to the soil over many seasons can adjust the pH enough that this weed can no longer grow.
12. Blue Fescue (Festuca glauca)
What It Does
This grass weed is usually grown as an accent or ornamental grass. However, because it thrives in the cool season and grows in mounds, it can quickly overtake too much of a lawn during the spring.
What It Looks Like
The leaves of blue fescue are green and blue and cut an intense contrast against traditional turf. Throughout the spring the spikey leaves produce bright green blooms. It can be identified by its mounding growth pattern.
How to Get Rid of It
If you find patches of blue fescue where it doesn’t belong you can pull them up by hand. If it is a larger spot and you need to resod quickly, you can apply an herbicide with glyphosate.
13. Foxtail (Setaria sp.)
What It Does
This lawn weed that looks like grass can be as tall as 40 inches and produces hundreds of seeds per foxtail plume. It spreads far by wind and can germinate in any moist and warm soil. Once it is established it can grow in clusters and invade a thin unhealthy lawn.
What It Looks Like
The green foxtail looks like a fast-growing grass while it is sprouting. The grass-like thin green stalks are topped by a fuzzy fox tail of seeds. When the seeds mature they fly away in the breeze.
How to Get Rid of It
You can use a spot treatment of vinegar to try and remove this weed grass. If you have a larger cluster you will need to apply herbicide regularly throughout the summer. Herbicides with acetochlor or non-selective varieties should take care of foxtails.
14. Slender rush (Juncus Tenuis)
What It Does
Grass weeds like this can establish themselves quickly through seed and rhizome propagation. Once it appears it looks just like turf grass making it hard to recognize before it matures. It tends to be very difficult to remove once it has spread and matured.
What It Looks Like
Slender rush has a thin and upright stem that is a medium green. It can grow up to 2 ft and its roots divide rapidly underground. It tends to grow in clumps like crabgrass and may be misidentified and improperly treated.
How to Get Rid of It
To remove small patches of this lawn weed that looks like grass you can dig up the entire clump and all the rhizomes. If there is a larger area than can be dug up you can increase the frequency by which you mow to prevent the speeds from maturing and spreading. Over time your rich lawn should choke the resort out.
15. Wild Onion and Garlic (Allium canadense and Allium ursinum)
What It Does
These weed grasses can quickly overtake extra fertile areas of the lawn. They grow sprouts quickly in the spring and go dormant throughout the summer. In the fall they produce seed heads. They can spread and take over a lawn if left alone.
What It Looks Like
In the early spring, the vivid green leaves look like a rapidly growing turf grass. They grow in clumps and outpace the rest of your turf grass between cuttings.
How to Get Rid of It
Since wild onion and garlic are edible the best option for removal is to manually dig them up. Then you can add to your table greens if you have been organically treating your lawn.
16. Dandelion (Taraxacum)
What It Does
Dandelions grow up undetected in lawns and produce incredible amounts of seeds that are spread by the gentlest breeze. They are very invasive and can completely cover a lawn.
What It Looks Like
This weed grass resembles crabgrass as it grows in clumps that push out to the sides. Once it reaches summer and begins to mature it produces recognizable yellow flowers. At the end of the season, those flowers become fluffy seed balls that quickly cover a thin dry lawn.
How to Get Rid of It
If you are proactive you can manage a dandelion infestation by manually pulling up the weeds as they sprout. Make sure you get the roots as they can be used as a coffee alternative. If there are too many to pull you can spot treat with a turf-safe herbicide and mow frequently to prevent seed balls from forming.
17. Yellow Salsify (Tragopogon Dubius)
What It Does
This lawn weed that looks like grass can grow quickly and invade a lawn. It grows in full sun and produces big fluffy seed balls in the fall. These can spread and take root all over a lawn and sprout all over the following spring.
What It Looks Like
Yellow salsify looks like other weed grasses with its thin stem and upright leaves. It produces yellow flowers in the summer and large wind-borne seed balls in the fall.
How to Get Rid of It
To keep yellow salsify out of your lawn, manually pull it up at first sight and regularly mulch areas that are susceptible to grass weeds.
Stopping Weeds that Look Like Grass Once and For All
As you can see, many lawn weeds look just like grass. Once these imposters make their way into your lawn it can be difficult to recognize them until they have become established. By going through this list you should have a much better idea of what these intruders look like and how to spot them on your lawn.
Once you have identified these problem weeds, you can use specific ways to get rid of the grass weeds above. Remember the best way to stop these weeds is by prevention. A well-fertilized, properly-watered, and thick lawn will stop many of these plants from ever getting started.
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