Managing Fescue During HOT Summers - Philosophy?

[PW405]

Ahh - that's really digging deep LOL!

I still really think it's more heat related for your (& mine) esp. if you have to really look for tell tale signs that closely.

You think that's digging deep? I present, the macro lens!



While I don't disagree that there is heat stress, especially in the areas that were only established in April, there is certainly some disease as well. I didn't do any preventative treatments, and now I'm kicking myself!

Plan to apply Scott's Lawn Fungus granules on Friday, and I've got some Honor Guard (Propiconazole) and Serenade on the way.

All - thanks again for all the feedback and suggestions! I should have soil test results later this week/early next week. Will this forum still interpret them if they are from an Agriculture university instead of Logan Labs?

[TimmyG]

Will this forum still interpret them if they are from an Agriculture university instead of Logan Labs?

See #3 in Posting A Soil Test for Interpretation.

If you're lucky, a non-ST6 member such as ken-n-nancy may take a stab at an interpretation and recommendation.

[PW405]

Ahh - that's really digging deep LOL!

I still really think it's more heat related for your (& mine) esp. if you have to really look for tell tale signs that closely.

How's this for close?! The macro lens!



While not very prevalent, I hope to get it under control soon. Going to spread the Scott's brand fungus control granules on Friday, and I've got some Propiconazole (Honor Guard) and Serenade on the way. Hopefully the Propiconazole will give some more rapid control, then I plan to apply Serenade regularly as a defense.

Soil test results could be here as early as tomorrow too.

[Green]

Good macro shot! Now fungal disease experts here should really be able to tell what your grass has.

As far as the fungicides go, you're going to want to rotate active ingredients most likely...to prevent resistance. The Thiophanate you bought is pretty broad-spectrum, so it should help halt various diseases.

The first step of course, is to verify which disease(s) this is/are, and then make sure the ones you bought are labeled for that.. Personally, I'm not sure, despite the great macro shots, but I'm not really an expert on lawn disease. I've had Brown Patch, Dollar spot, and a few others in the past. I hesitate to say that's Brown Patch for sure, because it looks different than when I had Brown Patch. Pretty certain it's not Dollar Spot though.

[PW405]

Good macro shot! Now fungal disease experts here should really be able to tell what your grass has.

As far as the fungicides go, you're going to want to rotate active ingredients most likely...to prevent resistance. The Thiophanate you bought is pretty broad-spectrum, so it should help halt various diseases.

The first step of course, is to verify which disease(s) this is/are, and then make sure the ones you bought are labeled for that.. Personally, I'm not sure, despite the great macro shots, but I'm not really an expert on lawn disease. I've had Brown Patch, Dollar spot, and a few others in the past. I hesitate to say that's Brown Patch for sure, because it looks different than when I had Brown Patch. Pretty certain it's not Dollar Spot though.

Thanks for the tips, I was noticing in this zoomed up shot, there is a bubbly red spot of sorts... perhaps a spore? (I know nothing about lawn disease).

I have noticed in my lawn & neighbors, there seems to be randomly dead spots of bermuda grass, which is fairly uncommon in my ~15 years of caring for lawns here. Perhaps our recent high-humidity weather has created excellent conditions for whatever this is

[PW405]

I placed my order yesterday for everything I need to make the Best Lawn Soil Conditioner (BLSC) and Kelp Help.

Soil test from local county extension came in yesterday and indicated low nitrogen & PH of 5.4. P&K were both high. Going to wait for test results from Logan Labs to get more conclusive results about how to best raise the alkalinity.

I applied a round of fertilizer about 1 week after submitting soil test, so hopefully the N is a little higher than what the test shows. Plan to pick up some N only fert this weekend.

Is there any causal relationship between low N and high acidity?

Have been mulching instead of bagging to help retain soil moisture.

Plan to apply Honor Guard fungicide tomorrow.

Again, thanks for all the contributions here! Plan at this point is to dial in everything as much as possible before mid-September over-seed.

[ken-n-nancy]

I applied a round of fertilizer about 1 week after submitting soil test, so hopefully the N is a little higher than what the test shows. Plan to pick up some N only fert this weekend.

Is there any causal relationship between low N and high acidity?

Whether or not the "N" component of the fertilizer affects pH depends upon the type of N used. The most common chemical "N" fertilizers (urea and ammonium sulfate) will have a minor acidifying effect, which will lower pH over time with frequent fertilization. One application isn't going to change much, but regular use of 4-6 pounds (of "N" per ksqft) of chemical "N" per year will push the pH downwards a couple tenths or so.

If you want to learn about some of the chemistry involved with why this is the case, google turned up an article on this for me from the University of Australia, titled Fertilizers and Soil Acidity.

[seiyafan]

Would it be a good idea to apply calcium once a year at bag rate (mag-i-cal) help with the change in pH?

[PW405]

Would it be a good idea to apply calcium once a year at bag rate (mag-i-cal) help with the change in pH?

See "KennNancy's" response from my thread in the soil management forums:

... the test indicates a markedly low pH (5.4), but without knowing the ratio of calcium and magnesium, it's not possible to know whether the lime to be added should be calcitic lime (providing calcium) or dolomitic lime (providing calcium and magnesium). Getting this wrong can lead to issues with soil workability that would be hard to fix afterwards. (It's far easier to raise pH by adding calcium or magnesium than it is to get rid of an excess.) For more information on liming products, see Andy's article, Lime and Your Lawn.

...results are a little odd, at least compared to what I would see in a New Hampshire soil. The low pH, combined with a satisfactory level of potassium, would be very odd for a soil in my area. However, apparently, that may be a pretty common circumstance in central Oklahoma based upon what I stumbled upon in an article on Oklahoma soils, Fertility of Oklahoma Agricultural Soils. However, before making choices of fertilizers based upon
such information, it would be important to have high confidence in the lab testing methods and consistency.

...if you take action without getting an additional test, that recommendation to apply 64 pounds of lime shouldn't all be applied at once (the test results you posted say this, too) and also makes presumptions about the type of lime being used (you wouldn't want to make a single application of 40 pounds per square foot of the fast-acting limes typically recommended by the ST6 gurus).

[ken-n-nancy]

Would it be a good idea to apply calcium once a year at bag rate (mag-i-cal) help with the change in pH?

Maybe. However, it'd probably be a better idea to get a detailed soil test done once a year and decide the amount of calcium, magnesium, and potassium application (all of which will affect pH) based upon that.

In that way, one's adjustment isn't just to just to neutralize the acidifying effect of the urea or ammonium sulfate fertilizer, but also measures what is there, to understand the impact of all the other factors which may be affecting pH (e.g. leaching due to rainfall, pH of watering (whether natural rain or irrigation), changes to soil chemistry due to the growth of plants, other fertilizers, decomposition of organic matter, etc.)

[PW405]

So yesterday I applied Honor Guard liquid fungicide. About 2-3 hours after, we had 10-15 minutes of light/medium amounts of rainfall. I'm wondering if this will effect HG's foliar fungus fighting ability?

[Owlnsr]

That's propiconazole, correct? Propiconazole is systemic... that rain will help the roots will soak it up.

[PW405]

That's propiconazole, correct? Propiconazole is systemic... that rain will help the roots will soak it up.

Yes, it is 14.3% Propiconazole. Good deal, I think it is OK, but I've never used the stuff before, so wasn't sure.

[bernstem]

Propiconazole is a systemic. It can be absorbed by the roots and will be transported up to the leaves. You should be fine as long as it wasn't washed past the root zone.

Fungicides won't bring back dead or brown turf. You will need to allow the damaged blades to grow out before the lawn returns visually. As long as the disease has stopped spreading the fungicide is working.

Fungicides should ideally be targeted at the disease. Very few fungicides are broad spectrum enough to kill the majority of lawn diseases, and many fungicides are impressively bad at killing non-labeled diseases.

When using different fungicides, you should also consider fungicide class and active ingredient. Obviously, even with different names, if the ingredients are the same they will work the same. Also consider fungicide class. Propiconazole and Tebuconazole, for example, are in the same class (the very similar names are a good hint) and can be consider similar enough to be essentially the same. That means mixing them, for example, is a waste of time and money, and, if you were looking for a broader spectrum of control, you won't get it. It also means that they count the same for fungicide rotation to prevent disease resistance.

[PW405]

Thanks for the advice Bernstem. I have little experience with fungicides, so this is helpful to know!

[PW405]

Got the call from Logan Labs today to take payment for my soil test. Hopefully that will reveal some useful information.

With the new watering schedule, a treatment of Honor Guard, and 1 application of BLSC and KH, and a round of N only fertilizer, the fescue is hanging in there better than I would have hoped a few weeks ago. Still haven't decided on an a cultivar for fall overseeding, but I think I'm on the right track thanks to the suggestion of members here.

I was considering doing some SPF 30 Kentucky Bluegrass in pots to make a "transition zone" between the fescue and bermuda sections. I have half a sack of SPF30 left over from last fall.

I wonder how that would work out? (In the image below, the bermuda is on the left side of the frame (east), fescue is under the giant tree.)

[Green]

Don't forget that since bluegrass is a prolific spreading grass (not like Bermuda when it's hot, but still prolific at spreading) it might not be the optimum choice if your goal is to create a demarcation line...the Bermuda will spread into the bluegrass, and the bluegrass will spread into both the Fescue and the Bermuda. If you don't mind everything mixing together, then go for it.

[PW405]

Don't forget that since bluegrass is a prolific spreading grass (not like Bermuda when it's hot, but still prolific at spreading) it might not be the optimum choice if your goal is to create a demarcation line...the Bermuda will spread into the bluegrass, and the bluegrass will spread into both the Fescue and the Bermuda. If you don't mind everything mixing together, then go for it.

My only concern for a mix would be if the colors were dramatically different. I know KBG tends to be a little lighter colored than fescue, but with a little iron treatment and Kelp Help (KH), I wonder how dark I could get the KBG? My bermuda is very close to being the color of fescue. i actually planted quite a bit of KBG last fall when I did my fescue overseeding, but I honestly can't tell if any of it sprouted and grew.

My reason for wanting to do use the KBG is that where the bermuda and fescue meet, there seems to be a "no man's land" where neither of them really grow too well.

[Green]

Most KBG is not lighter than Tall Fescue; some KBG is even darker than most Tall Fescue. I'm not sure about the hybrid bluegrass, though...those may in fact be a lighter green, and maybe that's what you meant. Pretty sure that Bermuda is a bit duller/grayer in general. I think you'd be able to see the three grass types if they were mixed.

[PW405]

Most KBG is not lighter than Tall Fescue; some KBG is even darker than most Tall Fescue. I'm not sure about the hybrid bluegrass, though...those may in fact be a lighter green, and maybe that's what you meant. Pretty sure that Bermuda is a bit duller/grayer in general. I think you'd be able to see the three grass types if they were mixed.

Oh great, I love the darker green shades of grass. I think I'm going to go ahead and start some KGB pots if nothing else just to see how it grows & looks. There are some backyard areas that could also benefit.

The giant tree creates varying amounts of light, so I was hoping that KGB's shade tolerance may help fill in a few of these areas a little better. This is roughly what I was thinking: