Diagnosing dead spots in lawn - Ask Extension
Last year my lawn developed multiple small dead patches in several areas. Wondered if my fertilizer drop caused it. This year it appears to be more ...
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Diagnosing dead spots in lawn #645884
Asked June 04, 2020, 12:11 PM EDT
Last year my lawn developed multiple small dead patches in several areas. Wondered if my fertilizer drop caused it. This year it appears to be more widespread so I'm thinking there's an underlying problem. Wondering if you have any guidance to diagnose and treat.
Thanks!
Thanks!
Adams County Colorado
Expert Response
Hello,
Thank you for your question. From these pictures it would appear that you may have a fungal disease called necrotic ring spot. This typically comes in lawns that have high fertility and are watered a lot especially in the spring season. It is a disease of kentucky bluegrass. I've got a really detailed fact sheet that I'll include below, but basically to manage this disease we recommend a multi-level approach: reduce watering in the spring if possible, eliminate early spring fertilization, and overseed with a seed mixture that includes ryegrass or fescue as neither of these are susceptible to the disease.
Please read through the fact sheet here: https://extension.colostate.edu/docs/pubs/garden/02900.pdf
note that even though this is a fungal issue, it is not one that is easily treated by fungicides, thus fungicides being the very last option listed in the fact sheet.
Please let me know if you have further questions!
Thank you for your question. From these pictures it would appear that you may have a fungal disease called necrotic ring spot. This typically comes in lawns that have high fertility and are watered a lot especially in the spring season. It is a disease of kentucky bluegrass. I've got a really detailed fact sheet that I'll include below, but basically to manage this disease we recommend a multi-level approach: reduce watering in the spring if possible, eliminate early spring fertilization, and overseed with a seed mixture that includes ryegrass or fescue as neither of these are susceptible to the disease.
Please read through the fact sheet here: https://extension.colostate.edu/docs/pubs/garden/02900.pdf
note that even though this is a fungal issue, it is not one that is easily treated by fungicides, thus fungicides being the very last option listed in the fact sheet.
Please let me know if you have further questions!
