Early-season Fungicide Applications and Spring Clean-Up
By Mike Agnew, Ph.D., technical services manager for Syngenta
As winter transitions to spring, you have an excellent opportunity to ensure a successful start to the 2021 season. A strategically planned fungicide program will not only help clean up any lingering winter diseases, but also serves as an excellent preventive approach to spring diseases.
By applying the proper product at the right time, you can start spring clean-up and precondition your course to reduce the severity of several diseases, including anthracnose and brown ring patch.
In areas with snow cover, evidence of Typhula blight (gray snow mold) can persist as the snow melts:
- Gray snow mold symptoms can appear as a light brown, gray or bleached patches ranging from a few inches up to 2 ft. in diameter. Leaves will appear matted. Curative fungicide applications usually aren’t needed. Instead, rake or otherwise break up matted tissues and lightly fertilize in early spring to encourage new growth.
- Microdochium patch, on the other hand, can occur any time from late fall to early spring whenever conditions are overcast, cold and wet, and at snow melt. A curative fungicide application, such as Posterity® XT fungicide at 2.25 - 3.0 fl. oz., is warranted in severely blighted stands.
Diseases such as yellow patch (Rhizoctonia cerealis) and brown ring patch (Waitea circinata) typically show up in the spring as temperatures begin to warm:
- Yellow patch occurs in the spring during periods of extended overcast, rainy and soil temperatures between 50° - 65° F. As a disease that impacts annual bluegrass and creeping bentgrass greens, collars and fairways, it is most severe when the thatch is cold and wet for long periods.
- Brown ring patch is a disease of annual bluegrass greens that is promoted by soil temperature ranges of 50° - 75° F, including overcast and rainy periods.
- Anthracnose (Colletotrichum cereale) can occur in conditions that range from cold and wet to hot and dry. This is a stress-related disease, primarily on annual bluegrass greens and collars. Weather conditions and cultural practices that enhance plant stress will make the plant more susceptible to infection. It has been demonstrated that seedhead suppression can exacerbate the disease; therefore, it is recommended to begin fungicides at the time of seedhead control.
- The timing of clean-up applications coincides with the first fairy ring applications in many regions of the country.
Click the link of each disease above for more information including management tips, identification photos and how to mitigate disease pressure. For additional diseases, visit our full disease ID guide.
Posterity XT, Ascernity®, Briskway® and Daconil® Action™ fungicides are excellent choices in the spring for the diseases listed above. Each contains multiple active ingredients that provide broad-spectrum disease control.
Posterity XT is a reliable tool for early-season applications that was recently added to the Syngenta product portfolio. It contains the active ingredient included in Posterity (pydiflumetofen), Heritage® brand products (azoxystrobin) and Banner Maxx® (propiconazole) fungicides and formulated in a concentration optimized for extended control of more than 25 diseases. It provides turfgrass protection from important spring diseases, such as anthracnose, brown ring patch and Microdochium patch.
Ascernity fungicide is another recently added product for early-season applications. It contains the active ingredients in SOLATENOL® technology and difenoconazole (an SDHI and DMI combination). This fungicide is an excellent greens option for controlling brown ring patch and anthracnose. It contains one of only two SDHI fungicides that control anthracnose while partnering with a cooling DMI.
Briskway fungicide has a recently updated expanded rate range on its label. Featuring a combination of a DMI (difenoconazole) and QoI (azoxystrobin), this fungicide makes it an excellent option to start your season.
For more information about spring clean-up, contact your local Syngenta territory manager.
©2021 Syngenta. Important: Always read and follow label instructions. Some products may not be registered for sale or use in all states or counties and/or may have state-specific use requirements. Please check with your local extension service to ensure registration and proper use. Action™, Ascernity®, Banner Maxx®, Briskway®, Daconil®, Heritage®, Posterity® and the Syngenta logo are trademarks of a Syngenta Group Company.