Leaf Spot/Melt Out??

Cool season grasses like Kentucky Bluegrass, Fescue & Rye
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Topic Author
dgrove12
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Leaf Spot/Melt Out??

Post by dgrove12 »

Newbie warning. Year 2 of taking lawn care seriously. Didn't do anything crazy to the grass so far this year. 3/4 lb of N via ProPeat in April. Another 1/4 recently post-aeration, at the recommendation of the company who did the work. Also spot sprayed Speedzone 3 weeks apart to clean up the weeds. Now my TTTF, KBG lawn is showing what I think is leaf spot/melt out. Looking for confirmation and thoughts about dealing with it.

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jha4aamu
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Re: Leaf Spot/Melt Out??

Post by jha4aamu »

dgrove12 wrote:
Thu May 13, 2021 3:06 pm
Newbie warning. Year 2 of taking lawn care seriously. Didn't do anything crazy to the grass so far this year. 3/4 lb of N via ProPeat in April. Another 1/4 recently post-aeration, at the recommendation of the company who did the work. Also spot sprayed Speedzone 3 weeks apart to clean up the weeds. Now my TTTF, KBG lawn is showing what I think is leaf spot/melt out. Looking for confirmation and thoughts about dealing with it.

Image
Can you wipe off that white stuff thats on the blades?
FRONT
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Topic Author
dgrove12
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Joined: Sat Jun 06, 2020 4:23 pm
Location: South Central Pennsylvania
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Mower: Toro Super Recycler 21382

Re: Leaf Spot/Melt Out??

Post by dgrove12 »

jha4aamu wrote:
Thu May 13, 2021 3:11 pm
dgrove12 wrote:
Thu May 13, 2021 3:06 pm
Newbie warning. Year 2 of taking lawn care seriously. Didn't do anything crazy to the grass so far this year. 3/4 lb of N via ProPeat in April. Another 1/4 recently post-aeration, at the recommendation of the company who did the work. Also spot sprayed Speedzone 3 weeks apart to clean up the weeds. Now my TTTF, KBG lawn is showing what I think is leaf spot/melt out. Looking for confirmation and thoughts about dealing with it.

Image
Can you wipe off that white stuff thats on the blades?
First time I've tried that, but yes... it does wipe off to uncover a yellowish-brown color. This is interspersed throughout the entire front yard. Strangely, I don't treat the back yard because of the dog. This condition doesn't exist back there. Is this my doing?

Also, forgot to mention that I had mixed tenacity in with the first Speedzone spot application.

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Re: Leaf Spot/Melt Out??

Post by Lawn Noob »

Rust, maybe?

jha4aamu
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Re: Leaf Spot/Melt Out??

Post by jha4aamu »

dgrove12 wrote:
Thu May 13, 2021 3:19 pm
jha4aamu wrote:
Thu May 13, 2021 3:11 pm
dgrove12 wrote:
Thu May 13, 2021 3:06 pm
Newbie warning. Year 2 of taking lawn care seriously. Didn't do anything crazy to the grass so far this year. 3/4 lb of N via ProPeat in April. Another 1/4 recently post-aeration, at the recommendation of the company who did the work. Also spot sprayed Speedzone 3 weeks apart to clean up the weeds. Now my TTTF, KBG lawn is showing what I think is leaf spot/melt out. Looking for confirmation and thoughts about dealing with it.

Image
Can you wipe off that white stuff thats on the blades?
First time I've tried that, but yes... it does wipe off to uncover a yellowish-brown color. This is interspersed throughout the entire front yard. Strangely, I don't treat the back yard because of the dog. This condition doesn't exist back there. Is this my doing?

Also, forgot to mention that I had mixed tenacity in with the first Speedzone spot application.
If you can wipe if off, id guess thats powdery mildew
FRONT
40% Mazama
40% Midnight
20% Champion GQ PRG

Topic Author
dgrove12
Posts: 21
Joined: Sat Jun 06, 2020 4:23 pm
Location: South Central Pennsylvania
Grass Type: TTTF, KBG
Lawn Size: 2650 sq ft
Mower: Toro Super Recycler 21382

Re: Leaf Spot/Melt Out??

Post by dgrove12 »

jha4aamu wrote:
Thu May 13, 2021 8:06 pm
dgrove12 wrote:
Thu May 13, 2021 3:19 pm
jha4aamu wrote:
Thu May 13, 2021 3:11 pm


Can you wipe off that white stuff thats on the blades?
First time I've tried that, but yes... it does wipe off to uncover a yellowish-brown color. This is interspersed throughout the entire front yard. Strangely, I don't treat the back yard because of the dog. This condition doesn't exist back there. Is this my doing?

Also, forgot to mention that I had mixed tenacity in with the first Speedzone spot application.
If you can wipe if off, id guess thats powdery mildew
Looks like Scott's Disease Ex addresses both leaf spot and powdery mildew. I'm tempted to let it go but I guess I'll get some and spread it out. I suppose it can't hurt anything. I'm not a fan of dumping so much stuff on the lawn and I wanted to try Milorganite for the first time soon. Maybe it'll have to wait.

Thanks for the feedback.

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Re: Leaf Spot/Melt Out??

Post by MachoManMooch »

If you didn't treat the backyard but did so for the front, maybe you hit it a little too hard with Nitrogen to start off the year? I think it could depend on temperatures and rainfall as well. Have you been getting a lot of rainfall recently?

Sometimes there can be so many factors involved! I always find my frontyard does better in general with than my backyard with respect to fungal pressure. My backyard, however, has a tendency to stay a little more moist than the front (sun coverage, yard slope).

Topic Author
dgrove12
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Re: Leaf Spot/Melt Out??

Post by dgrove12 »

MachoManMooch wrote:
Fri May 14, 2021 4:54 am
If you didn't treat the backyard but did so for the front, maybe you hit it a little too hard with Nitrogen to start off the year? I think it could depend on temperatures and rainfall as well. Have you been getting a lot of rainfall recently?

Sometimes there can be so many factors involved! I always find my frontyard does better in general with than my backyard with respect to fungal pressure. My backyard, however, has a tendency to stay a little more moist than the front (sun coverage, yard slope).
Ya know, I thought that too. I'm new to all this. It's the spring after my first fall overseed, which went very well. I figured 3/4 lb of N was light to "wake up" the yard. I regret listening to the guy who aerated and suggested to spoon feed more N when the holes were open. In retrospect and for next year, I'll use something slow-releasing like Milo.

Even if it is excessive N, wouldn't the treatment be the same? It doesn't look like I "burned" the yard, at least from what I can tell. It looks like legit disease. Wouldn't I still want to apply Disease Ex?

Topic Author
dgrove12
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Re: Leaf Spot/Melt Out??

Post by dgrove12 »

Ok, so I don't think it was my doing. I looked more closely in the back yard where I don't fertilizer or treat at all. It suffers from the same issue.

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Harts
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Re: Leaf Spot/Melt Out??

Post by Harts »

It looks like powdery mildew. It's affects are primarily aesthetic. Chemical control can be done if the appearance is intolerable. Headway G will help.

Powdery milder typically develops because of poor air circulation and/or excessive N.

Are these areas in the shade for a good portion of the day?

Check out this article: https://www.extension.purdue.edu/extmed ... -111-w.pdf

Topic Author
dgrove12
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Joined: Sat Jun 06, 2020 4:23 pm
Location: South Central Pennsylvania
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Re: Leaf Spot/Melt Out??

Post by dgrove12 »

Harts wrote:
Fri May 14, 2021 11:16 am
It looks like powdery mildew. It's affects are primarily aesthetic. Chemical control can be done if the appearance is intolerable. Headway G will help.

Powdery milder typically develops because of poor air circulation and/or excessive N.

Are these areas in the shade for a good portion of the day?

Check out this article: https://www.extension.purdue.edu/extmed ... -111-w.pdf
The lawn on the each side of the house has it worst, for sure. Those spots get full sun for 4ish hours a day as it passes by, but it's definitely more shaded than the front and back lawns. The poor circulation makes a lot of sense. I mow high and I have a HUGE thatch issue (>1"). It's been my main focus for the 2 years I've been doing this, with light dethatching and aeration twice a year as attempted corrective actions. The thatch just never goes away. The adjoining property has grass that is beyond spongy... like walking on a pillow. It greens up in the spring and fall but I really want a healthy lawn that does better in the Pennsylvania summer heat and all that thatch just does not help matters.

I wouldn't say the aesthetics of the disease are intolerable... it certainly triggers my OCD though :) I just got back from Home Depot and will probably put down the Disease Ex at the preventative or slightly higher rate. I'm curious to see if it has an affect.

Appreciate all the feedback.

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Harts
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Re: Leaf Spot/Melt Out??

Post by Harts »

Have you ever rented a power rake from Home Depot and done a heavy dethatch? It sounds as though you may need to get aggressive with it.

Are you sure it's thatch? Greater than 1" after aerating and light dethatching twice a season makes me thing it isn't thatch.

Are you able to pull a core sample and post a picture of the soil profile?

Topic Author
dgrove12
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Joined: Sat Jun 06, 2020 4:23 pm
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Re: Leaf Spot/Melt Out??

Post by dgrove12 »

Harts wrote:
Fri May 14, 2021 1:03 pm
Have you ever rented a power rake from Home Depot and done a heavy dethatch? It sounds as though you may need to get aggressive with it.

Are you sure it's thatch? Greater than 1" after aerating and light dethatching twice a season makes me thing it isn't thatch.

Are you able to pull a core sample and post a picture of the soil profile?
I'm pretty sure it's thatch. Both times I've aerated, only the tips of the plugs were soil.... the rest was thatch. You could pull it apart like a slinky. If you dig your fingers into the lawn, it's VERY difficult to get through that layer to the soil. I'm certain water has a hard time finding it's way through. This is only the second season I've tried to address it and every time I do, the lawn turns to hell. Turns brown because the majority of the roots are shallow and in thatch, NOT in soil. It's better this spring. The Hogan seed is doing ok but I did a light raking last week and it's browning up already. I'll try to take some pictures. It sucks.

I agree though. I may rent the power rake and get crazy with it this fall.

EDIT: See attached pics that show more disease and the thatch. Hard to see, but I had to dig deep to get to soil and it looks devoid of any nutrition. It's like dust lol.
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