What is this stuff in my yard?

Over the years, I've become less inclined to maintain my lawn with fertilizer and weed control, but that's all caught up to me now. I've used Ortho Weed B Gon on the clover and the crabgrass, so I have a strategy for those, but I'm not sure what this stuff is.

Hopefully it can be identified to be sprayed and killed or stopped with pre-emergent. It started out as 2' circles and now occupies large swaths.

Could it be Bermuda grass?

Thanks in advance for any thoughts.

I don't think it's Bermuda grass. My best guess is this is the same stuff. Found this larger specimen at the edge of the property.

bsruther said:

There are a lot of weed type grasses. What about nimblewill, I think it might be a bermuda grass variation, not sure.
I have a constant battle with weeds in the yard, plantain, knotweed, clover, crabgrass you name it. Never ending battle.
I really hate the plantains, especially the broadleaf one.

Click to expand...

When I first got a house, I figured I'd get the yard done and that'd be it! Man, was I in for a surprise. My conclusion is that there is nothing other than yard "maintenance". I'd be kicking myself in the spring for fertilizing it and having to mow every 4-5 days, but it could look so gorgeous in the fall.

What I read about Bermuda grass indicated it's a long-term fight. This stuff looks really close except for the seeds. Suppression was the only word used by websites. And I thought Creeping Charlie and Honeysuckle were going to be the worst...

The bright side is it's not Kudzu?

Hey, I think you totally NAILED it with Nimblewill. Web photos are identical. OK, now it's time to see what my options are!! Thanks!

Brother Bart, over the 12 years I've been here, many's the time it was the only green stuff in the yard. I can't believe how persistently this stuff is on the march.

Here's what I found on a Purdue website.
Chemical control: There are nonselective and selective control options available for nimblewill. Usually, stoloniferous, perennial grasses are controlled by spot-treating with a nonselective systemic herbicide such as glyphosate (Roundup). For best results, apply when the plants are young and actively growing. However, because nimblewill is capable of re-establishing through surviving stolons, at least two glyphosate applications are recommended, but three or more may be needed for complete eradication. It is important to allow the weed to regrow before making any follow-up applications.

Two new herbicides provide selective control options for nimblewill in cool-season turf. These herbicides are applied at relatively low use rates and homeowners are encouraged to hire lawn care professionals to make applications.

Mesotrione (Tenacity) can be used for selective control of nimblewill growing in a cool-season turf. To control nimblewill, start applying mesotrione in the spring (late-April) with a nonionic surfactant at 0.25% (v/v). You will need to make two or three applications. If you make three applications, use the 5 fl oz/A rate (or 6, 6 and 4 fl oz/A). The product does have a yearly maximum use rate, and the label states “do not apply more than 16 oz of Tenacity per acre per year or per crop (equivalent to a maximum of 0.50 lb of mesotrione per acre per year).” You can also apply mesotrione in late summer and fall, but you should initiate them by August for best results.

Another option is to apply topramezone (Pylex) at 1-1.5 fl oz/A at 21- to 28-day intervals starting in late April. For best results, include a methylated seed oil at 0.5-1.0% (v/v).

When we moved in I was really gung-ho to get a lawn going because cutting grass was a big chore growing up (and I liked it), and this place had severe erosion, so I had to do something. So between seed and sod I got front, back and side done. I always tried to spread any chemicals thinly, because I secretly referred to Dad as "Chemical Ali" when he'd have a spill or pour a runway strip out in the yard, and I realized I have to drink that stuff, too.

I had it managed down to mainly water and spot-killing dandelions, but we lost so many trees the whole thing changed. I've been overseeding with the low-water tall fescues, but that drought+full sun a couple summers ago really gave a leg-up to this Nimblewill.

With all the scrounging and splitting this summer, I don't have the ambition to Round-up 3X, till, seed and water. Even though the patches are big, I'll still be spot treating them with my 5-gallon back-pack (or jet pack, as my wife calls it).

I ordered Tenacity and got it applied 9/16. $60 for 8 oz and also bought surfactant. Thought it to be hugely expensive until I confirmed the mix ration is 1/2 Tsp/Gl. They actually include a syringe so you can draw the product in and measure it. It is w/o a doubt the most fiddly to mix stuff I ever worked with. I concluded to mix in a 2 Gl bucket by adding surfactant first, then Tenacity, then stir, then pour in my 5 Gl sprayer.

The photos don't reflect 100% of the treatment (no side yard, etc), but I did 16 gallons of spot treatment. It's crazy; the sprayed stuff is turning white. It's not brown and burned, it's like the chlorophyll gets sucked out. If things get any whiter, I'm going to add it to my laundry.

Though it's supposed to be selective, if a blade of grass is wide enough it's got a white stripe through it. The narrow blades can be unaffected.

I'm not sure now whether to spray again to achieve a complete kill, or let the grass to try outcompete it, or throw some seed in there and spray the Nimblewill once or twice next year.

Here are some close-ups. You can see the grass with a zebra stripe, and it's very hard to tell if the Nimblewill has been affected down the entire length of the stalk. Time will tell.