# What is killing my Tall Fescue?



## uncken (Oct 14, 2021)

I decided to start a new thread because this seems completely separate from my previous issue and on a totally different and unconnected area of my lawn, and I feel like my lawn is at risk of needing another complete reno if I don't figure out how to stop what's happening.

Pictures:







I started noticing these yellowing spots even on the areas of my lawn, so I decided to fertilize (since I hadn't since seeding) with granular Urea at .25N/1k and watered in, followed the next week with Simple Lawn Solutions 28-0-0. I noticed no change, and started to see the grass wasn't just yellowing, but turning brown/gray and dying off.

I have put down 1 application of DiseaseEX at the curative rate, and 24-hour grub killer, and this past week I did an application of Propi at 2oz per 1k sq ft - though I used a hose end sprayer and not a backpack sprayer.

I am watering twice per week with a hose pretty deep watering in order to hit ~1"/week everywhere. The ground has not been soggy - if anything, it was a bit more dry than normal the week of Halloween because we were busy. Temps have been in the 40's at night and 60-70s in the day here in the Piedmont area of NC.

I'm not sure what to do at this point, but happy for any advice or I can take additional pictures, etc.


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## Delmarva Keith (May 12, 2018)

Do you have soil test results? My knee jerk reaction to the pics is fungus on baby grass but your temps don't jibe with out of control fungus. I think I see lesions on some of the live blades but it's hard to tell from the photos. I'd suspect a deficiency of some sort (first thought is lack of potassium but you need a soil test) that is either killing it or making it overly susceptible to fungus.


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## uncken (Oct 14, 2021)

I don't have soil test results unfortunately (live and learn), but I just ordered two MySoil kits (which I know is not well liked on here, but seemed to be the fastest way to get some results while we still have a bit of warm weather).

Absent a soil test, would you recommend I put down some more starter fertilizer? I have some starter left over (18-24-6) that I could put down, but not sure at what rate.. the label says 3.2lb/1k initially.

I could do another application of DiseaseEx or Propi, but not sure about doing more Propi within a week of a previous application..


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## Delmarva Keith (May 12, 2018)

Can't know what to do without data. It's getting a little late in the season to fertilize. Since it's not clear what's wrong and you already applied a fungicide, all I can tell you is what I would try at this point - pick a maybe 5' x 5' area and apply the starter at about 0.5 lb N per 1,000 (3.2 lb of product per 1,000 is close enough). Wait a week or preferably two and see what happens. If the turf still alive improves, apply the fert to the rest of the lawn and hope for the best in terms of continued growing season weather. If it doesn't improve or seems to get worse on the test area, then something else is still wrong.


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## Grass Clippins (Apr 30, 2018)

How much 28-0-0. I did you put down? Sounds like you might be in the process of loving it to death. My overseeding is looking rough this year because my soil temps are about 10 degrees lower than normal. It's taking forever for things to get rolling with these cooler temps. If I were you I would do nothing and see how it looks in the spring. I'll be doing my winterizer next week but you may not need it depending on how much 28-0-0. I you put down.


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## g-man (Jun 15, 2017)

For background information:

https://thelawnforum.com/viewtopic.php?p=453772#p453772


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## nikmasteed (Apr 30, 2020)

Grass Clippins said:


> Sounds like you might be in the process of loving it to death.


This has been the best way to characterize what I've been thinking as I read through your other thread and now this one. You've clearly put alot into this reno, so I get it, but lawncare is a marathon not a sprint. I'd recommend getting the soil test as you're planning, because it'll help you gameplan in the spring. Aside from that, unless this issue is spreading rapidly, I would cut my losses and just keep mowing until it stops for the year. You'll have a base off of which to improve in the spring. Given the amount of products you've put down lately, I'd be hesitant to put down more, even fert.

That's me, maybe someone will be able to help actually pinpoint your problem. Good luck!


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## uncken (Oct 14, 2021)

Thanks for the advice all - for the 28-0-0, it was a Simple Lawns Solution sprayer advertised at covering ~3200 sq ft. I have a bit over 2k sq ft, so I used about 2/3rds of the bottle on the lawn. It wasn't super precise. I would say maybe a bit more than 2/3 if anything.

The soil testing kits are coming today, so I'll be shipping them out tomorrow at the latest, hopefully have results by next week.

I decided to rip out a few strands of grass to get some closer pictures and check for grubs (I did not see any, but have already put down an application of 24 hour grub killer, so that didn't surprise me). The pics to me look like it may be Gray Leaf Spot - what do you all think?





If it's that, is it worth another application of DiseaseEx (~2 weeks ago) and another application of Propi next week with a backpack sprayer? I also ordered some Clearys 3336f just in case/to have on hand for the spring.


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## tgreen (Oct 20, 2018)

Your last set of pics looks a lot like gray leaf spot with the fish hook pattern of die back from the tip but your pics are missing the characteristic lesions of GLS. If that was GLS then the disease should die with a frost and certainly would die with a freeze. I don't know your recent weather but I personally would not treat for anything, including GLS, this late in the season.

Here's a pic of a GLS lesions on tall fescue for reference.



and also pics of tall fescue seedlings succumbing to GLS. Notice the fish-hook but if you zoom in you can make out the lesions.


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## uncken (Oct 14, 2021)

Thanks for the advice. I also read the other thread that made a good point where if the fungus isn't growing due to temperature, then it doesn't really matter how much fungicide you put down as it isn't feeding/growing.. so that makes sense.

I got my soil testing results back and was REALLY surprised at what it says my level of P is (excessively high). It also says my Nitrogen is low (which makes sense since high P can fix available N for the plants), and I wonder if this could be part of the cause for some of the dieback?

Here's the results:





Any advice on how to lower P in my yard? I know the MySoilTest isn't a fan favorite here, so not sure exactly how accurate it is, but since I've done basically the same thing to both sides of the yard and both independent samples are showing excessive P, it stands to reason that it's at least seeing similar issues on both sides.


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## Green (Dec 24, 2017)

@tgreen, what's the fish hook? The blade tips curling down? And is it a hallmark of GLS on seedlings?


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## tgreen (Oct 20, 2018)

uncken said:


> I got my soil testing results back and was REALLY surprised at what it says my level of P is (excessively high). It also says my Nitrogen is low (which makes sense since high P can fix available N for the plants), and I wonder if this could be part of the cause for some of the dieback?
> 
> Any advice on how to lower P in my yard? I know the MySoilTest isn't a fan favorite here, so not sure exactly how accurate it is, but since I've done basically the same thing to both sides of the yard and both independent samples are showing excessive P, it stands to reason that it's at least seeing similar issues on both sides.


Your soil is not causing that. Your PH is optimal. Nitrogen is used quickly and is not usually tested. Remember, this is a soil test, not a test of the amount of nitrogen in the plant.

I don't see organic matter concentration which is usually reported. I have clay soil and excessive P as well. It has never been a problem. I would post your soil test on the soil fertility forum. Don't be surprised if they suggest that you use a different lab. Good luck.


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## tgreen (Oct 20, 2018)

Green said:


> @tgreen, what's the fish hook? The blade tips curling down? And is it a hallmark of GLS on seedlings?


The fishhook is not unique to seedlings with GLS, it also occurs on more established plants. Unfortunately, I don't have any great pics of that particular feature. The lesions are probably the better ID but I would say the fishhook adds more certainty to the ID. You really want to get it tested though if you suspect GLS. Here's the other pics I have. If you look really close, you can see lesions and the die-back from the tip on a couple blades.


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## uncken (Oct 14, 2021)

tgreen said:


> Green said:
> 
> 
> > @tgreen, what's the fish hook? The blade tips curling down? And is it a hallmark of GLS on seedlings?
> ...


I do see some spots like that on some of the turf, I just can't really get a close enough picture it seems like. And the blades are pretty thin being so young, so maybe that's why they're not showing up?

It warmed up for a couple of days here, so I put down another application of Propi and Clearys 3336f just on the off chance that the cold weather hadn't killed anything. I felt like it couldn't hurt anything but if whatever it was started growing again I wanted something to head it off before it spread any further. I'll have a bunch of stuff on hand to rotate through in the spring when I overseed to fill in some of these spots.


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## uncken (Oct 14, 2021)

tgreen said:


> uncken said:
> 
> 
> > I got my soil testing results back and was REALLY surprised at what it says my level of P is (excessively high). It also says my Nitrogen is low (which makes sense since high P can fix available N for the plants), and I wonder if this could be part of the cause for some of the dieback?
> ...


I'll do a crosspost there, thank you! I've sent off for our state lab as well, but they're several weeks out and I wanted at least to have some sort of preliminary information while we're still getting some days in the 70's. I'm going to put down another application of Nitrogen (either Urea diluted in my tank sprayer or another 28-0-0 from Simple Lawn Solutions) this week


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