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Guidelines for the Use of Chlorothalonil for Anthracnose on Putting Greens in Massachusetts

The Commonwealth of Massachusetts protects public drinking water supplies by restricting the use of specific pesticides in primary aquifer recharge areas (either 'Zone II' or Interim Wellhead Protection Areas). The Public Drinking Water Supply Protection Regulations do not apply to wells that pump less than 100,000 gallons per day. When applied to established turfgrass (more than 50% groundcover), pesticides on the Groundwater Protection List may be used only if it has been determined that there is "no viable alternative," but a MA Department of Agricultural Resources (MassDAR) approved Integrated Pest Management (IPM) plan must be followed. MassDAR has a website available for "no viable alternative" pesticide uses:

At this time, there is no viable alternative to the use of chlorothalonil for anthracnose on putting greens located within Zone II or IWPA areas. If you wish to use chlorothalonil for anthracnose in such an area, you must:

  1. Obtain a diagnosis, at least once, from a diagnostic lab and keep the report in your records. Information for submitting samples to the UMass Extension Plant Diagnostic Lab and the case history sheet are available online at:

  2. File the Notification Form with MassDAR within 10 days of the end of each calendar month in which chlorothalonil is applied (you also must record all applications of chlorothalonil on the IPM Program form listed below.) The Notification Form can be filled in online and submitted directly to MassDAR:

  3. Obtain a copy of the UMass Extension fact sheet "Anthracnose-Why is it so Difficult to Control?"
  4. Manage anthracnose using the MassDAR-approved Turf Anthracnose Management Approved IPM Program and maintain the required records with your pesticide application records. This is available at the MassDAR website listed above or directly by using the link below. You can print out the PDF and fill in the information by hand.

If you have questions about these requirements, you may contact MassDAR through their website or by calling (617) 626-1700. If you have questions about the diagnosis and/or management of anthracnose on turfgrass, please contact the UMass Extension Plant Diagnostic Lab.


Dr. Gail Shuman, 2011: revised by Dr. Angela Madeiras, 2021
Last Updated: 
January 2021