Solution sheet Patch – Cool Season // The Problem Microdochium patch (Microdochium nivale) can be a tough problem on cool-season turf from the fall through early . This disease is also known as ‘ patch’ in older references, and is caused by the same pathogen responsible for pink mold. Microdochium patch develops in cool to warm, wet weather as opposed to pink snow mold that develops under extended snow cover. What To Look For Symptoms start off as small, water-soaked spots on turf that expand and turn gray or tan with a red-brown or dark, greasy-appearing margin. Fluffy, white mycelia can be observed at the edge of the patches, and often, dead tissue is covered by pink masses. Wet conditions during maximum daytime temperatures of 45-68°F favor this disease, and explosive outbreaks can occur when daytime temperatures are in the low to high 60s with overcast, foggy or wet weather. It is most common on cool- season turf, especially annual bluegrass, but can occasionally occur on warm-season turf such as bermudagrass and seashore paspalum. This disease is favored in shaded or poorly-drained locations and excessive nitrogen fertility conditions. // The Solution Interface® Stressgard® is a proven solution for Microdochium patch with excellent preventive and curative activity. Interface Stressgard can also help turf recover from pink snow mold damage following snow melt. Interface Stressgard contains two fungicidal modes of action and provides plant health benefits for turf growth promotion under cool and low-light conditions when Microdochium patch is most active. Interface Stressgard provides great disease control plus improved turf color and density when you need it – in cool, wet weather. Apply Interface Stressgard at 4-7 fl. oz. per 1,000 sq. ft. as a preventive or early curative treatment. 26GT® is also effective for Microdochium patch control, and offers flexibility as a stand-alone application or as a tank-mix partner. Tartan® Stressgard can be used as part of a fall or disease control program when additional broad-spectrum or patch disease control is needed. Bayleton® FLO, Mirage® Stressgard, and Compass® 50 WG and Exteris® Stressgard are best when used as tank-mix partners to control Microdochium patch and other diseases that may be active at the same time. Rotate classes when multiple applications are used in the season for Microdochium patch control to prevent resistance development. Addition of a multi-site fungicide when making curative applications will also help minimize resistance development. Microdochium Patch Solutions

Solution1 Rate (per 1,000 sq. ft.) Application Interval

Interface® Stressgard®2, 4 4.0 - 7.0 fl oz 14 - 21 days 26GT®3, 4 4.0 - 8.0 fl oz 14 - 21 days Tartan® Stressgard5 2.0 fl oz Fall - early spring

® 6 Apply before conditions are Bayleton FLO 1.0 - 1.9 fl oz favorable for disease Mirage® Stressgard7 1.0 - 2.0 fl oz 10 - 14 days Apply before conditions are favorable Compass® 50 WG8 0.2 - 0.25 oz for disease in fall - early spring Apply before conditions are Exteris® Stressgard9 4.1 - 6.0 fl oz favorable for disease 1See fungicide labels for complete details. Always read and follow label instructions carefully. 2Do not exceed more than 30.0 fl. oz./1,000 sq. ft. or 6 applications/year. 3Do not exceed more than 35.0 fl. oz./1,000 sq. ft. or 6 applications/year.4 Products are only labeled for Microdochium (Fusarium) patch in the Pacific Northwest, registration in additional states is pending. See updated product labels for additional state registrations. 5Do not exceed 345 fl. oz. of Tartan Stressgard/acre/year. Do not make more than 3 sequential applications. 6Do not exceed 3.8 fl. oz./1,000 sq. ft./year. Bayleton is not registered for Microdochium (Fusarium) patch control in California. 7Do not exceed 6.5 fl. oz./1,000 sq. ft./year, except in New York state where the maximum of three 1.0 fl. oz. applications/year can be used. 8Do not exceed 34.5 oz./acre per year. Do not make more than 3 sequential applications for Microdochium (Fusarium) patch control. 9For Exteris Stressgard, Do not exceed 12.6 fl oz/1000 sq ft per year.

Early symptoms of Microdochium patch developing on an Typical symptoms of Microdochium patch on annual bluegrass showing annual bluegrass green; initial symptoms may be mistaken bleached patches with a reddish edge. (Bayer) for dollar spot. (Bayer)

Active Microdochium patch will produce aerial Pink sporodochia of Microdochium nivale on infected at 25X in the early morning or after incubation in a moist chamber magnification. Each sporodochium contains thousands of fungal overnight. (Bayer) conidia. (Bayer)

ALWAYS READ AND FOLLOW LABEL INSTRUCTIONS Bayer Environmental Science, a Division of Bayer CropScience LP, 5000 CentreGreen Way, Suite 400, Cary, NC 27513. For additional product information, call toll-free 1-800-331-2867. Not all products are registered in all states. Bayer, the Bayer Cross, Interface, Stressgard, 26GT, Tartan, Bayleton, Mirage, Compass and Exteris are registered trademarks of Bayer. © 2019 Bayer CropScience LP. ES-1018-GCS-474-A-R1