Located on our Lake Wheeler Turf Field Lab, this green has a history of Pythium root dysfunction and fairy ring problems, and we were also hit with Pythium root rot last year during an extended period of wet weather. Dollar spot, brown patch, and algae are also problems on this green as they are on most bentgrass greens.
We used an excel spreadsheet to assist with developing the program. The diseases we need to control were listed at the top, with each column across the sheet corresponding to a week during the growing season. Using our knowledge of the weather conditions that trigger each disease and historical weather data from the State Climate Office of North Carolina, we highlighted the weeks that each disease is likely to be active. This gives you a good visual image of what diseases need to be controlled with each fungicide application. We used the Disease Management Utility on Turffiles to select a fungicide or tank-mixture that would control the diseases that are expected to be active during each week. We tried to avoid having to make fungicide applications on back-to-back weeks, but in several cases we needed to do that because application methods (foliar vs. watered-in) were not compatible.
Here's the program we came up with:
March 14: Segway (0.9 fl oz, watered-in)
April 4: Bayleton (1 fl oz, watered-in)
April 11: Honor (1.1 oz, watered-in)
May 2: Torque (0.6 fl oz, watered-in)
May 9: Signature + Banol (4 oz + 2 fl oz)
May 23: 26GT + Fore (4 fl oz + 6 oz)
May 30: Terrazole (4 oz, watered-in)
June 6: Disarm C (5 fl oz)
June 13: Subdue Maxx (1 fl oz, watered-in)
June 20: Honor + Fore (1.1 oz + 6 oz)
July 5: Signature + Daconil Ultrex (4 oz + 3.2 oz)
July 11: Segway (0.9 fl oz, watered-in)
July 18: Disarm C (5 fl oz)
Aug 1: Stellar + Daconil Ultrex (1.2 fl oz + 3.2 oz)
Aug 15: Spectro + Alude (5.76 oz + 6 fl oz)
Aug 29: Subdue Maxx + Fore (1 fl oz + 6 oz)
Sept 12: Reserve (3.2 fl oz)
Sept 26: 26GT + Daconil Ultrex (4 fl oz + 3.2 oz)
If this seems like a lot of applications and an expensive program, you're absolutely right. Several of these applications are specifically to control Pythium root rot, which can develop any time between May and October in North Carolina depending on when the wet weather comes. This is why adjusting your fungicide program based on the current conditions is so important - many of these Pythium applications could be avoided if the weather is dry and unfavorable for Pythium root rot development at that time.
This year we'll be comparing this NC State program to other common fungicide programs, and one that we adjust on the fly based on the current weather conditions, to see which method provides the best disease control and highest turf quality.
For more information about our Program '11 Project, or to follow along on Facebook or Twitter, please visit our website turfpathology.org.
No comments:
Post a Comment