Grass is dead in multiple spots over the last few weeks.

SD,
over the last 2 weeks or so a bunch of patches of dead grass have appeared.

We have had very little rain this summer until last weekend when we got nearly 8 inches in 2 days from Hurricane Gordan remnants. I checked both my adjoining neighbor’s yards and they do not appear to have this issue. The biggest difference between our yards is that I do have a lawn service for weed and grub control and fertilizing etc. The grass is flat. like its matted matted down.

This is in southwest Ohio also.

Thanks for any help in advance,
Cncdad

Fertilizer burn? If your neighbors don’t have this problem, seems like your service might have overdone it, thinking the heavy rain would make it okay to apply extra.

I’m no expert, to start with. If it were me I would ask my service what they think, and whether further efforts, like de-thatching and re-seeding, should be taken. If I didn’t trust my service enough to trust their advice, I would find another service.

Dog pee?

That sounds a lot like fertilizer burn, as suggested. Either by dog pee or by fertilizer not being dispersed properly.

Sod webworm
It looks like water stressed grass and grows out in increasing circles

.

With fertilizer burn the grass would would turn bright yellow before it died and dead patches would have bright yellow edges.

Do you have dogs?

Nemotodes?

Looks like grub worm damage to me.

Yeah, I have similar spots in my front yard. But I’m in a different region, have what looks like different grasses in my yard, and it was happening in the front where the dog doesn’t really go. I figured it was june beetle larvae. After we had some rain in July/August, the native ranch grass moved back in before the st. augustine did. So, it’s green and happy right now. If I get hit with the same patches again next year, I’ll treat for them.

It could be a fungus like brown patch. Brown patch can develop in warm weather when the grass is continuously wet for at least 10 hours. It is “particularly severe in turf that has been fertilized with excessive nitrogen.” Brown Patch in Turf | NC State Extension Publications

It doesn’t look like nitrogen burn / dog pee spots to me; looks like a fungus, likely brown patch. When you look at the lawn in early morning do you see little sparkles kind of looking like dew and / or can you see something that looks like little clouds or mist in the grass? That’s fungus.

Brown patch and the like are brought on by high humidity and warm overnight temperatures and exacerbated by strong nitrogen fertilization. There are fungicide treatments available; they do work but are somewhat expensive and don’t last very long. The fungicides don’t get rid of the fungus, just stops them temporarily; it will always be in your lawn, waiting for the right conditions to make a comeback. Using a low nitrogen fertilizer (something like Milorganite) in the hot months may help.

I think your problem will mostly clear up as the weather cools and the lawn will be pretty much recovered by mid October. It’s a little late for over-seeding now; plan on over-seeding in early spring if you want.

Could be fungus as Turble details above.

To check for grubs, grab a handful of the grass and pull. If there are grubs, the grass will pull right up and you’ll see them.

To check for chinch bugs, look closely when hot & sunny where there are still green blades. They are small with white wings crossed over their backs that look like an X.

Sod webworm will show webbing in morning dew and moths above the grass in the evening, or when disturbed by mowing.
The Best Time To Seed

Thanks all. another bit of data, it’s only in the front yard where it gets full sun all day. no shade at all where as the back is shady most of the day.

I did the grub check and its not grubs. and we have no dogs although lots of rabbits that are eating my plants. I will have to wait a couple days to see if there is anything on the grass in the morning.

Cncdad

Agreed that early fall is the best time to plant grass seed (actually, you can plant grass seed at any time – but early fall is best and spring is second best) but I think is a bit late. In the Northeast the usual time is right around Labor Day. You may have some success if you get it down quickly, however, new seed needs to moistened at least once and preferably twice a day … and damp grass is probably the problem right now. If you do over-seed now many of the seeds that don’t germinate this year will sprout in the spring, so it wouldn’t hurt.

I suggest you get one of those hose-end sprayers of lawn fungicide available at most any hardware store and apply it … the stuff works pretty fast and with ideal growing conditions for grass coming right up you will likely see a major recovery.

Something like Bayer Advanced Natria Concentrated Liquid Fungicide

Then be ready to over-seed in the spring – when the overnight soil temperature reaches 50 to 55 degrees (depending on the species of seed) and which is when the forsythias begin dropping their flowers.

I had a similar die off two years ago and also confirmed it wasn’t grubs.
It was never fully diagnosed but I do recall reading about brown patch and thinking it was a prime suspect.
My next door neighbors weren’t affected but I saw it on other lawns in the area which was …reassuring?

I tried that straw or excelsior matting to put down over the new seed in the fall and recommend it very highly.

Looks like chinch bugs to me. Here, they’re more black than white.

I went out and definitely saw a few of the sod webworm moths along with quite a few very tiny white moths that are maybe slightly larger than a gnat. I tried the soapy water in a couple places but could not see any webworms coming out nor any frass.

here are 2 more up close picture. its almost like 2 different issues.

The 1st picture is grass that is in the fairly large area, maybe 2 x 2 that seemed to appear in a very short time. the grass pulls out in chunks.

The 2nd I dug into the dirt a little with my fingers and was able to pull it back fairly easily but not what I have normal had to do with grub damage before.

Lasty we have not seen many if any at all June bugs or japanese beetles this summer and at best we have seen a few moths around the lights.

Thanks again everyone.

Cncdad

It looks like some kind of insect damage to me as well. My sons lawn had patches sonewhat similar and it turned out to be ants.

If it is some kind of insect be sure to use a product that is specific for lawns. Regular insecticide can do even more damage to grass.