Lawn problem/Leshinsky

Asked August 12, 2020, 11:16 AM EDT

I have something going on with my lawn is creating a big ugly dead spot. It started about the first week in June and then the patch was about 3' x 3' and now has grown to what you see in the photos that I have attached. Please make note of the photo where the grass is beautiful and healthy, right next to the trouble spot.
I have treated it with both a fugus and insect over the counter common products. I have not seen any type of improvement with either product. Also did the cinch bug test and did not see any type of insect with that rudimentary test.
Any suggestions would be welcome.

El Paso County Colorado

7 Responses

Thank you for your pictures and question.

How often do you water and fertilize? Did you core aerate this year? Do you have children and/or pets? Do you hand water or do you have a system?

We water 3 times a week, more if it is really hot. Fertilize quarterly.
We did aerate last year, and have wondered if the infection/problem may have been on the equipment used.
No children or pets. We have a automatic system and have checked the coverage, seems to be adequate

Thank you for your response. We will keep going with questions:

How many minutes for each zone? Have you actually witnessed the coverage for a full cycle spraying water on that area?

Side Note:
It is unlikely caused from the aeration equipment used.

I will get this information and get back to you. I appreciate your help with this.

We are watering 8 min. 2x a day 3- 4x a week. Did watch the watering cycle in that area and all was good.

Thank you for your patience. We have not forgotten you. I am conferring with my colleagues.

Thank you for your patience.

After consulting with my colleagues we agree that you may have ascochyta leaf blight. Normally we would recommend that you bring a sample into the extension office, where a Master Gardener would take a closer look under the microscope. Unfortunately, the Corona-Covid virus prevents us from doing that.

Below are two links provided by Colorado State University regarding this disease. Please read them and let us know if you have any additional questions.