Sod several months old, now has several areas of "rusty blades". See picture.

[MowerMark]

Our old bluegrass lawn was >20 years old and we never had the problem described below.

A few months ago 80/20 Blue/Rye sod was installed. Watering 20 minutes 3x/week starting at 5AM. Mowing to 1.5 inches. In the past two weeks, areas of "rust" has appeared on some blades, but not in all areas of the lawn.
We have used professional high nitrogen fertilizer every month, more than recommended.

Article on grass rust (and it doesn't seem like rust is the problem): https://www.thisoldhouse.com/lawns/what-is-grass-rust-and-how-to-remove-it

Anyone here know what this is and how to cure it?

 

[Auto Doc's]

Our old bluegrass lawn was >20 years old and we never had the problem described below.

A few months ago 80/20 Blue/Rye sod was installed. Watering 20 minutes 3x/week starting at 5AM. Mowing to 1.5 inches. In the past two weeks, areas of "rust" has appeared on some blades, but not in all areas of the lawn.
We have used professional high nitrogen fertilizer every month, more than recommended.

Article on grass rust (and it doesn't seem like rust is the problem): https://www.thisoldhouse.com/lawns/what-is-grass-rust-and-how-to-remove-it

Anyone here know what this is and how to cure it?

Cut back on the water and definitely the fertilizer. Let nature take care of itself without so much intervention.

 

[MowerMark]

Cut back on the water and definitely the fertilizer. Let nature take care of itself without so much intervention.

Thanks, Doc. However the saying of "common things happen commonly" might apply here. A moisture meter shows each of these rusty grass areas to be dry to very low, and the ground is difficult to pierce with a sharp object, consistent with the area being super-dry.

I don't like the Toro 4" pop up nozzles...;. they do not spray evenly and especially leave a void close to each head.

Will try watering the largest of the rusty areas and report back here.

Does anyone here know how to improve the spray patterns of the Toro adjustable nozzles?

 

[slomo]

A moisture meter shows each of these rusty grass areas to be dry to very low, and the ground is difficult to pierce with a sharp object, consistent with the area being super-dry.

Dump more water then. If you can't punch a screwdriver into the dirt, too dry.

Watering 20 minutes 3x/week starting at 5AM.

You seriously need to be looking at a minimum 40+ minutes per zone. 20 min 3x a week, from an irrigation system, is nothing. All brands are said to "save water' meaning throwing less water ON your grass. In 85F plus temps, you are shy on water.

I don't like the Toro 4" pop up nozzles...;. they do not spray evenly and especially leave a void close to each head.

Go Rain Bird. Never look back.

Does anyone here know how to improve the spray patterns of the Toro adjustable nozzles?

Which nozzles are you running? Don't try to run them wide open. To me, all perform better if you diffuse the water stream into a more misting pattern.

 

[MowerMark]

Dump more water then. If you can't punch a screwdriver into the dirt, too dry.

You seriously need to be looking at a minimum 40+ minutes per zone. 20 min 3x a week, from an irrigation system, is nothing. All brands are said to "save water' meaning throwing less water ON your grass. In 85F plus temps, you are shy on water.

Go Rain Bird. Never look back.

Which nozzles are you running? Don't try to run them wide open. To me, all perform better if you diffuse the water stream into a more misting pattern.

Thank you. YES... areas are dry. Have called the sod and irrigation installer. Using 15 ft. adjustable Toro nozzles with center screw NOT moved.

1. should I first try turning the center screw clockwise until the spray is altered?
2. will RainBird nozzles fit the 4" Toros?
3. is there a specific model of RainBird nozzle you recommend?

Twenty minutes per channel seems okay since many areas measure high with moisture meters; so this is more a matter of dispersion.

 

[MowerMark]

Oh my! I mowed the lawn and a golden brown powder coated the inside of the grass collecting bag, so there must be a big time fungal infection in the lawn. I've never experienced this in my >40 years of caring for a lawn.

Is this due to the sod grower? Bad luck? Something we did in caring for the lawn?

Is this a reason why the entire lawn is not as green as the prior lawn? The lawn has received fertilizer and ironic and did not respond like prior lawns.

How would you treat now this disease?