Make a plan
A preventative management plan that combines cultural practices and fungicide application is necessary for Microdochium patch in the Pacific Northwest. Management tactics will need to be adjusted throughout the season because the disease can be especially tough on cool-season turf from late summer through spring in British Columbia. It can harm all cool-season grasses, but is most damaging on low mown annual bluegrass. Once turfgrass growth slows, it becomes very difficult to get rid of Microdochium patch symptoms until warmer temperatures prevail in early spring. Here are some recommended cultural practices and fungicide considerations for your management plan.
• Maintain low soil pH – below 6.5
• Control excessive thatch with cultivation practices
• Remove morning dew, improve air movement and provide adequate drainage
• Roll when not mowing – rolling can reduce Microdochium incidence
• Balance soil fertility and increase Sulphur fertilization to 2.5 lb./1,000 ft2 per year
• Initiate fungicide applications once air temperatures fall below 15⁰C
• Rotate modes of action to actively manage fungicide resistance
• Apply fungicides every 28 days – intervals may need to be shortened during peak pressure
• Enhance control using pre-mix fungicides or tank-mix fungicide combinations
• Ensure your fungicide program is compliant with new PMRA regulations
New PMRA regulations
• Iprodione based products – all Iprodione based products, including Interface™ Stressgard® and Trilogy® Stressgard® must be used by June 21, 2021. All purchases must have been made by June 21, 2020.
• Chlorothalonil based products – all applications of chlorothalonil based products at rates labeled for snow mould must result in the immediate closure of treated areas to the public. This affects Instrata®, Daconil® and other generic formulations containing chlorothalonil.
• Click here for more information on PMRA regulatory changes with these active ingredients.
Interface and Trilogy can also help turf recover from pink snow mould damage following snow melt.
Remember – Interface and Trilogy can be used to control Microdochium patch until June 21, 2021.
A comprehensive fungicide program should include multiple modes of action while practicing fungicide rotation. Fungicides should be applied preventatively as temperatures begin to cool in early fall. Maintain applications if environmental conditions remain conducive for Microdochium patch development.
Below is an example of a fungicide program designed for effective season-long disease control of Microdochium Patch throughout the fall, winter and spring months. This program is a suggestion only, based on consistent disease pressure throughout the season. Always refer to product labels for specific instructions for each application.
For more information about disease and insect control strategies, contact your local Territory Sales Manager.
Bayer, the Bayer Cross, Dedicate Stressgard, Interface Stressgard, Trilogy Stressgard are trademarks of Bayer.