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SD Mesonet Small Grains Tool
The SD Mesonet Small Grains Disease tool helps producers understand the possiblity that diseases may be impacting crops based on modeling from recent local weather conditions.
Step one: Select a station near your field from the dropdown or map below.
Infection periods of tan spot, Stagonospora (Septoria) blotch and leaf rust
Step Two: Using the dropdown below, select the stage of growth. Then, select the date when 50% of your flag-2 or flag-1 leaves had disease symptoms on the graph below.
Consider a fungicide when the bar graph has passed the colored background thresholds indicating 6 to 8 days of risk.
Steps One and Two must be completed for this graph to display.
Fusarium Head Blight (Scab) for Wheat
Step Three: Select Spring or Winter wheat. Find the your grain variety (column) then select the date (row) your field came into flower. Finally, assess the risk of scab via the color displayed.
Interpretation: This model estimates the percent risk of serious head blight.
Red indicates scab is more likely than not.
Yellow indicates a moderate risk of scab.
Green indicates that scab is unlikely.
Steps One and Three must be completed to display this graph. The growth stage from Step 2 must NOT be Boot or Flagging.
Many factors that influence plant diseases are used within the modeling process. You can visit our Archives or Archive Maps to compare measured weather information to your local conditions.
Credits and further information
The models used in this prediction were originally developed by NDSU Small Grains Program. SDSU takes no responsibility in fungicide application decisions. This is only a guide. Growers should scout individual fields and make their decisions based disease level in comparison to what is being predicted.
For further information please visit SDSU Extension or more info.
Questions and comments can be emailed to