How to Use the South Dakota Mesonet Small Grains Tool

Written collaboratively by Ciera Kotaska, Madalyn Shires, and Connie Strunk.

The South Dakota Mesonet Small Grains Tool is a tool for South Dakota growers to help identify the disease risk for small grain crops based on local weather data collected by the South Dakota Mesonet stations. This easy-to-use and efficient tool can help identify disease risks associated with wheat leaf rust, wheat leaf spot diseases, and Fusarium head blight. It is important to note that this is only a tool to assist with management decisions. If the risk of disease is high, please scout your fields before considering fungicide application and consult with SDSU Extension plant pathology specialists or agronomists as needed. This article serves as a guide for using the SD Mesonet Small Grains Tool. To get started using the tool, click or tap the button below.

Using the Small Grains Tool

Step 1. Location Selection

SD Mesonet Small Grains Tool location input with “Cottonwood” selected. For a detailed description, please call SDSU Extension at 605-688-4792. — Select the station closest to your field from the drop-down area. For this example, we’ll be selecting the “Cottonwood” station.

Step 2. Disease Selection

SD Mesonet Small Grains Tool “Disease Selection” input fields for leaf diseases and Fusarium Head Blight. For a detailed description, please call SDSU Extension at 605-688-4792. — Determine if you are estimating disease risk for “Leaf Diseases” (tan spot, Stagnospora blotch, and leaf rust) or “Fusarium Head Blight” of wheat.

Step 3. Leaf Diseases - Growth Stage Selection

SD Mesonet Small Grains Tool “Leaf Disease” growth stage selection input. For a detailed description, please call SDSU Extension at 605-688-4792. — For leaf diseases, select the current growth stage of your field from the options listed (flagging, boot, heading, flower, or milk).

Step 4. Leaf Diseases - Growth Stage Output

SD Mesonet Small Grains Tool leaf disease output graph. For a detailed description, please call SDSU Extension at 605-688-4792. — After you have selected the current growth stage, a bar graph will appear of the past 7 days of risk based on weather conditions for that area. By clicking on a specific day, you will be able to look at the risk prediction for that day in a white pop-up box. If you see consistent disease risk for your field, scout your field to identify any disease present in your field before considering making an effective fungicide application.

Step 5. Fusarium Head Blight - Grain Selection

SD Mesonet Small Grains Tool “Fusarium Head Blight” grain selection input. For a detailed description, please call SDSU Extension at 605-688-4792. — For Fusarium Head Blight for wheat, select whether you are growing spring wheat or winter wheat.

Step 6. Fusarium Head Blight - Grain Output

SD Mesonet Small Grains Tool “Fusarium Head Blight” grain selection output chart. For a detailed description, please call SDSU Extension at 605-688-4792. — After wheat selection, you will be shown the average risk for each day across four different susceptibility levels (very susceptible, susceptible, moderately susceptible, and moderately resistant). It is important to know what the disease ratings for your wheat varieties are in order to effectively use this map.

Related Topics

Wheat Diseases

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