Round mounds of grass in my lawn

Question: Is this an undesirable grass? It sure looks bad because it’s in big round tufts all over the back yard. It grows much thicker and taller than the rest of the grass and bogs my mower down. I read that it’s because of my dog urinating and adding nitrogen to those areas. I hate using weed killers so I’d like to know if it’s a weedy grass first. Thank you in advance. You are all so helpful and informative.

responder: An Ask Extension Expert Replied May 01, 2023, 6:02 AM EDT
response: Hello,  Based on what I see in your images - I believe your problem is quack grass. There are several options for trying to discourage, remove or eliminate it from turf.  Option 1: Management Many folks have effectively "eliminated" quack grass by masking its presence in the lawn. This is usually accomplished by increased nitrogen fertilization and increased mowing frequency. (Just what everyone wants, mowing more often!) This approach has been implemented with relative success by more than a handful of turf managers. The idea is that the quack grass only has a competitive advantage when the desirable grass sits idly by. By increasing the vigor of your lawn, you will choke the quack grass, make it darker green, and, for the most part, make it disappear.  This method could be accomplished by fertilizing your lawn with 0.25 to 0.5 pounds of nitrogen per 1,000 square feet every two weeks during the growing season. If this ends up being one of those dry summers, you would definitely want to suspend this program because unless you’re irrigating, the turf will not be able to use the nitrogen. If you follow this program, you will notice that the quackgrass patches are much smaller next spring.  Option 2: Mechanical removal Due to the perennial nature of quack grass and its well-developed rhizome system, it is very difficult to remove by mechanical means. Methods include digging up the offending patches, including several inches of soil and replacing them with new topsoil, and reseeding. However, the rhizomes of quack grass can grow 6 to 8 feet deep in the ground, and these rhizomes could potentially "push" new plants to the surface.  Another option is solarization. This method uses clear plastic fastened securely to the ground over the quack grass areas. Be sure to cut the plastic slightly larger than the patches. Leave the plastic in place for five to seven days in the spring or summer when the weather is nice. The plastic will help trap the heat close to the soil surface and hopefully devitalize the plant material. After removing the plastic, you may reseed the area.  Option 3: Non-selective chemical removal - Roundup! Use a non-selective herbicide like Roundup to kill the patches. Keep in mind that non-selective means that it kills whatever plant it touches. This method will create dead patches in your lawn that can be re-established. In our opinion, you will need to apply the Roundup twice. Make the second application 14 days after the first. Seven days after the second application, you can rough up the area and sow your new grass seed.  Quack grass is an insidious, rhizomatous, perennial grassy weed that infests turf and ornamental beds. Quack grass stands out in turf this time of year due to its rapid top growth. This is a one-time-of-year occurrence due to the top growth difference when quack grass could be effectively wicked with a non-selective herbicide such as glyphosate to kill the quack grass without injuring the desirable turf. A weed wick is a braided rope that gets soaked with herbicide - and then would be dragged across the taller blades of the quack grass. Getting rid of quack grass is tough. Wicking should work with Round-Up, and they will never be 100 percent, and you will most likely kill off some turf. By using glyphosate, you can quickly follow up with seeding those areas. When you use herbicides, be sure to read and follow the label and wear the appropriate personal protective equipment.   Option 4: Do nothing Obviously, quack grass is green and takes mowing. You may decide after looking at the other options that it is better than bare soil. From the article: Quack grass control in the turf at this link: https://www.canr.msu.edu/news/quackgrass_control_in_turf   Check out the following links for some additional information Quack grass now appearing in the turf at this link: https://www.canr.msu.edu/news/quackgrass_now_appearing_in_turf Quack grass - MSU at this link: https://www.canr.msu.edu/ipm/diseases/quackgrass  I hope this helps!

responder: Dick M.  Replied March 15, 2024, 4:46 PM EDT
response: Until I looked at your photos I thought you might have tall fescue growing in your lawn.  I don't think the photos show that clearly (not enough detail).  It looks like healthy cool season turfgrass that needs to be mowed.  I do see some tall fescue grass clumps in the photo with the shed.  More info here: Pain In The grass: Tall fescue-MSU Turfgrass identification - Ohio State Most of the lawn looks to be (non-weedy) cool season turfgrass. The best ways to eliminate the tall fescue are mechanically (digging) or with non-selective herbicides (glyphosate). I recommend doing a soil test on your yard. Knowing the type and fertility of your soil is the starting point to establishing & maintaining a strong turf that can resist diseases, weeds, moss and insects/grubs, look great and at an optimal cost. More info here: Don't Guess-Soil Test-MSU and MSU Home Soil Test-self mailer  Your lawn looks fairly healthy in the photos (taken last year?).   More lawn care info in these links: Why Mow High-MSU  Lawn Weed Control Options-UMN Smart Lawns Tip Sheets-MSU  MSU Turf disease ID  Home Lawns | MSU Extension

responder: The Question Asker Replied March 16, 2024, 10:31 AM EDT
response: Dear Dick, thank you for responding. The photos I sent originally were all taken this year.  I believe this will be the third year of dealing with this strange grass. I’m including pictures from last year to show what it looks like once the mowing process starts. It’s kind of gnarly and yellow underneath all that green. I read an article about “mowing out” unwanted grasses and gave it an attempt although I later read it might make it worse. I did attempt to mow the affected areas real low every few days for a while last year. The thing I don’t understand is why it grows so much faster than the rest of my lawn, why it grows in clumps, and worst of all, why it bogs my mower down? We had a dry summer in 2022 and the lawn wasn’t growing much but then one day I notice seed stalks poking up everywhere. I went out there and hand picked them in case it was something unwanted but I don’t know if I got to them in time before they released the seeds. I’m also including a side by side of a picture of tall fescue that was in an article you sent me and what my strange grass looks like today. If there’s a specific photo you need to identify I’d be more than happy to get it for you.My neighbor who has a lawn like a carpet thinks it might be because of mole activity which is aerating the ground underneath, trapping water and causing thick, mushy grass?Lastly it seems suspicious that this thick clumping grass started in my yard and is now invading my next door neighbor’s yard. Would good desirable grass do that? Thank you, JoyceSent from my iPad On Mar 15, 2024, at 4:46 PM, Ask Extension <<personal data hidden>> wrote:﻿

responder: Dick M.  Replied March 17, 2024, 9:46 PM EDT
response: I have reviewed grass identification info and must admit I don't know the identification of the plant growing in your lawn.  It's time to send you to MSU Plant & Pest Diagnostics  (MSU Plant & Pest ID) for an answer.  Open the 'contact us' button and you will find contact info for Dr. Erin Hill the Weed Science Diagnostician.  I recommend you send her an email.  Tell her your concern about the grass growing in our yard and attach the photos you have put in Ask Extension.  Also, provide a detailed description of cultural practices (irrigation, fertilization, pesticide application, etc.) for her knowledge in providing an answer.