dollar spot?

[mitch88]

Recently (2 weeks ago) fertilized and also put down lime at the same time. Now I have brown spots or patches...in the morning looks like a silky spider web on the top of the grass. Is this dollar spot? Is this from too much nitrogen? How do I fix it?

Thanks,
Mitch
Acworth, Georgia

[marko]

could be. Could also be Pythium or brown spot. All of these can have the cotton or spider web appearance when there is dew on the ground. Can you git a close up picture of some affected grass blades? I think dollar spot usually is a tan lesion on the blade, sometimes bordered by maroon or brown, in the shape of an hourglass.

[GreenUtah]

Here are some useful pages for identifying and managing various turf diseases.

http://turfgrassmanagement.psu.edu/turfdis5.cfm

http://grounds-mag.com/mag/grounds_maintenance_unfab_five/

http://www.ipm.uiuc.edu/diseases/series400/rpd408/

http://extension.usu.edu/plantpath/turf/turf_disease_utah.htm

http://extension.usu.edu/plantpath/

[ThreeWide]

My viewpoint might help since I'm located near you.

Several of the Bermuda lawns I manage have developed Dollar Spot over the last week. This is mainly because of the persistent wet weather we've had. Another contributor to DS is low N. Since you fertilized 2 weeks ago, it might not have had enough time to take effect. Remember it was very dry until last week. If you used a good bit of slow release, the temps have been too cool for that as well.

You didn't mention what turf type, but if it is Bermuda chances are you have DS. Brown patch usually doesn't happen until we have much hotter and humid weather.

The form of N that I applied on my lawns was slow release, and our cool weather has slowed that process as well. Since the N didn't release much since my application, the constant cool and wet conditions triggered DS. At least that is my theory.

I will be applying 1/2 lb per K of Urea to try and remedy the DS situation. If that doesn't help, fungicide will be the next step.

This weather here has been driving me nuts.

[goforgreen2]

First off urea is a source of N not K. The best way to determine if you're dealing with brown patch is to look at the burn back, if there is a purple line separating the burn and green it's bp. If you've been dry lately, you could be looking at drought stress.

[ThreeWide]

In my post above K=1000 sq ft, not the symbol for Potassium.

[mitch88]

My viewpoint might help since I'm located near you.

Several of the Bermuda lawns I manage have developed Dollar Spot over the last week. This is mainly because of the persistent wet weather we've had. Another contributor to DS is low N. Since you fertilized 2 weeks ago, it might not have had enough time to take effect. Remember it was very dry until last week. If you used a good bit of slow release, the temps have been too cool for that as well.

You didn't mention what turf type, but if it is Bermuda chances are you have DS. Brown patch usually doesn't happen until we have much hotter and humid weather.

The form of N that I applied on my lawns was slow release, and our cool weather has slowed that process as well. Since the N didn't release much since my application, the constant cool and wet conditions triggered DS. At least that is my theory.

I will be applying 1/2 lb per K of Urea to try and remedy the DS situation. If that doesn't help, fungicide will be the next step.

This weather here has been driving me nuts.

Thanks Turf. It's definitely DS. This is in the front yard where I have bermuda. Your right about the weather, this constant hard rain in the afternoons is not making it any better. I found more of it this morning. I guess I need to use a fungicide at this point to keep it from spreading any more. Is it better to try and stay away from the fungicide? Is there any you recommend? Can it only be applied when it's dry for a period of time??

Mitch88

[ant]

yeah what TurfUnlimited said....

sit

[ThreeWide]

DS has gotten worse by the day around here this week.

Since several of mine have DS right now, I've went back and applied about 1/2 lb per thousand of 46-0-0. This should help it push through the DS. If not, fungicide will be necessary.

I like to try the cheap and easy solution first.