If you were at field day on August 3rd, you likely saw the experimental area that was highlighted by Dr. Megan Kennelly. A turf-type tall fescue blend has been treated the past two years as either: High N level; or Low N level. High level involved 4.5 lbs of N/1,000 ft2/yr (Months applied listed in lbs N/1,000 ft2 – 1 in April; 1 in May; 1.5 in Sept.; 1 in Nov) and low N level was 1.5 lbs of N/1,000 ft2/yr (single application in September). In addition, half of the plots receiving these treatments either received two fungicide applications from azoxystrobin (Heritage) each growing season or none. You’ll see a photo below of how N impacted brown patch on tall fescue. More details will come out in the 2024 K-State Turf Research Report. Bottom line summaries:
- High N levels provided high quality turf, but fungicide application was required to maintain it when brown patch infection began. Turf receiving high N without fungicide declined quickly in quality starting in July.
- Brown patch levels were comparable in July in turf receiving high N from standard urea, humic coated urea, or combinations of 50% slow release + 50% quick release N.
- Low level N generally provided turf quality that was at or just below an acceptable level (but not high quality) and had little brown patch even when fungicides were not applied.
Impact of N level on brown patch in tall fescue with no fungicide application.
