Poa Triv? Thats whats invading my lawn currently because my Pre-em didnt go down early enough.

You'll notice the light green grass grows taller/faster than the other grass around it. If thats the case its probalby Poa.

 

From the close up photo, it looks like the beginning of a late season fungal outbreak. You can see some lesions forming (discoloration in certain sections)on several leaf blades, and there are already some dead/brown blades present.

 

Poa Triv? Thats whats invading my lawn currently because my Pre-em didnt go down early enough.

You'll notice the light green grass grows taller/faster than the other grass around it. If thats the case its probalby Poa.

Not sure that it's Poa as the light green grass actually seems to be growing slower than everything around it.

 

From the close up photo, it looks like the beginning of a late season fungal outbreak. You can see some lesions forming (discoloration in certain sections)on several leaf blades, and there are already some dead/brown blades present.

I'm leaning this way. I put down some Azoxystrobin to fight off a Pythium blight issue I had about a month so I would suspect that it wouldn't be anything under that umbrella.

I was mowing with dull mower blades but I've swapped them out and noticed a big difference in my last cut. If it's fungus I'm not really sure where to go from here. Will the cold kill it off?

 

The cold might kill it off. Have you hit first frost or average first frost yet? If you haven't, you might be able to grow it out with spoon feeding some urea.

 

The cold might kill it off. Have you hit first frost or average first frost yet? If you haven't, you might be able to grow it out with spoon feeding some urea.

Yeah, I've been putting down about 1/3 lb of Urea a week for the past 3 weeks.

 

@Greensby I recognize that look. I saw it in my big reno last year, and I've noticed it in other reno lawns this year. I don't have a clear answer, but here is what I think:
Sharp blades are important, but I don't think that happened because of dull blades.
The mind always goes to N deficiency, but it sounds like you've got your bases covered there.
Iron perhaps?
In my own situation, I tried to link it up to overly saturated soil or excess moisture on the blades. That could lead to some kind of fungus. However, I could never draw a conclusion. The discoloration was present for most of the winter, with varying severity. In early spring, it promptly disappeared.

If I were to encounter this again, I would not panic. I would be mindful of putting extra water down in this area. I would test for compaction or subsurface rocks. I would give some thought to fungicide apps (though I would pass on this). I would make sure that I am not missing the areas with my N apps. And then I would look to spring, hoping that it regains its color and starts a growth pattern consistent with the rest of the grass.
FWIW

 

The cold might kill it off. Have you hit first frost or average first frost yet? If you haven't, you might be able to grow it out with spoon feeding some urea.

Yeah, I've been putting down about 1/3 lb of Urea a week for the past 3 weeks.

Where you at in NE Tennessee?

 

This looks similar to the problems I'm seeing in my lawn. I have been thinking I need to sharpen my blade, and the areas are particularly thick, so could be related. Are your areas shallow rooted at all? I wasn't too concerned about mine until I was able to pull them up so easy, just a light pinch and a pull and I'd bring a whole bunch of growth up.

 

The cold might kill it off. Have you hit first frost or average first frost yet? If you haven't, you might be able to grow it out with spoon feeding some urea.

Yeah, I've been putting down about 1/3 lb of Urea a week for the past 3 weeks.

Where you at in NE Tennessee?

Tri-Cities area, why do you ask?

 

@Greensby I recognize that look. I saw it in my big reno last year, and I've noticed it in other reno lawns this year. I don't have a clear answer, but here is what I think:
Sharp blades are important, but I don't think that happened because of dull blades.
The mind always goes to N deficiency, but it sounds like you've got your bases covered there.
Iron perhaps?
In my own situation, I tried to link it up to overly saturated soil or excess moisture on the blades. That could lead to some kind of fungus. However, I could never draw a conclusion. The discoloration was present for most of the winter, with varying severity. In early spring, it promptly disappeared.

If I were to encounter this again, I would not panic. I would be mindful of putting extra water down in this area. I would test for compaction or subsurface rocks. I would give some thought to fungicide apps (though I would pass on this). I would make sure that I am not missing the areas with my N apps. And then I would look to spring, hoping that it regains its color and starts a growth pattern consistent with the rest of the grass.
FWIW

Could be overly saturated soil. I'll look at the sprinkler placement a little closer when I get home. Though, I haven't watered since last week after my Urea application. I'll check for compaction, but that would also be surprising since i just put down a few tons of nice, loose top soil and compost over the entire lawn prior to the reno. Sub-surface rocks could also be an issue because I'm not sure what was under the existing lawn pre-reno.

All of these are great suggestions! thanks!

 

This looks similar to the problems I'm seeing in my lawn. I have been thinking I need to sharpen my blade, and the areas are particularly thick, so could be related. Are your areas shallow rooted at all? I wasn't too concerned about mine until I was able to pull them up so easy, just a light pinch and a pull and I'd bring a whole bunch of growth up.

Haven't looked at root depth yet. But as another poster suggested if I do have root depth issues, I may have some sub-surface rocks that could be causing the issue.

 

Yeah, I've been putting down about 1/3 lb of Urea a week for the past 3 weeks.

Where you at in NE Tennessee?

Tri-Cities area, why do you ask?

I'm in the the same area. About 20 minutes from Johnson City. I think we are the only ones east of Knoxville that I have seen.

 

Here's a few more pictures of a different spot. You can really tell the difference between the healthy fescue and the part that is struggling. It seems like the pattern seems to roughly follow mowing lines, but may just be me trying to associate it with something. If it's a fungus, I'm having a hard time ID-ing. The brown tips and lack of growth is what's concerning me the most right now.

 

Did you tug on it to check for shallow roots yet? A long screwdriver will detect sub soil rocks. Have you core aerated in the last two years? Stolons spread by core aeration would cause the same striping pattern.

 

Did you tug on it to check for shallow roots yet? A long screwdriver will detect sub soil rocks. Have you core aerated in the last two years? Stolons spread by core aeration would cause the same striping pattern.

Checked for shallow roots and it seemed well rooted. Screwdriver test didn't seem to hit anything of notice. No core aeration at all. This one is really throwing me for a loop. The only thing I've come across that looks similar is pythium root, but I think I would have loose roots, and I treated pythium about a month ago..

 

That is pretty good news for you. Keep an eye on it, but don't sweat it too much and don't forget to watch it again in the spring.

 

How long does the azoxy remain active?
I believe I see lesions in the last set of pictures.

 

The images are out of focus. I cant see the leaf damage too good. I see 3 possibilities: lack of nitrogen, leaf spot or maybe gray leaf spot. When was the last time you fertilize? What rate of azoxy and how far back? more than 30days? I also dont see TTTF in the area struggling. Is this a reno?

 

Any slow release in the urea fertilizer?

 

How long does the azoxy remain active?
I believe I see lesions in the last set of pictures.

Im not exactly sure, but the bad says I can re-apply at 14-28 day intervals. So maybe that long?

 

The images are out of focus. I cant see the leaf damage too good. I see 3 possibilities: lack of nitrogen, leaf spot or maybe gray leaf spot. When was the last time you fertilize? What rate of azoxy and how far back? more than 30days? I also dont see TTTF in the area struggling. Is this a reno?

1.Lack of nitrogen - I would be surprised if it were this, as I have been applying about 0.3 lbs/M per week for the last 3 weeks.
2. When was the last time you fertilize? - Last Friday, the 26th
3. What rate of azoxy and how far back? I used the curative rate of Scott's DiseaseEx which is 4lbs/M and applied on Oct. 6. So, getting close to the 30 day mark.
4. Is this a reno? - This is a reno, and in the newest pictures, the only grass that was planted there was TTTF so if it's anything else then it's unwanted. In the the first pictures its a mix of KBG and TTTF.

 

Any slow release in the urea fertilizer?

Nope. Just double checked the bag and its all Urea nitrogen.

 

I think you ruled out Nitrogen issues. Soil/pH is all good per a soil test?

Melting out (leaf spot type) is a risk in a new grass/reno. I would do more fungicide, but funicide is not always successful in a reno.

Check the fungicide guide. This link has specific info on efficiency and re-application intervals. Azoxy is 14-21 days.
http://www2.ca.uky.edu/agcomm/pubs/ppa/ppa1/ppa1.pdf
https://www.extension.purdue.edu/extmedia/BP/BP-103-W.pdf

 

I also like the disease explanation best at this point.
I just looked at a neighbor's newly established fescue lawn yesterday evening, and I saw a very similar pattern to yours. I suggested that he look into treatment with a fungicide or wait it out over winter to see if it will recover on its own during the spring. I did the latter last year, and it worked out fine, but I don't remember seeing lesions on mine.

Putting faith in the resilience of the fescue vs treatment: IMO, that's a complicated and personal decision.