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BEAN WHITE MOLD - FUNGICIDE DECISION STRATEGY
See Bean Pesticide Summary for pesticide details
Colorado State University Integrated Pest Management Program
CHECKLIST FOR APPLICATION Your Score
 Current Season Rainfall, Dew, Humidity from Planting to V - 4 Stage  
 Above Normal: 2  Normal: 1  Below Normal: 0
Current Season Temperature from Planting to V - 4 Stage  
Below Normal: 2  Normal: 1 Above Normal: 0
Forecasted Rainfall, Dew, Humidity Between V - 4 and R - 4 Stages  
Above Normal: 2  Normal: 1 Below Normal: 0
Forecasted Temperature Between V - 4 and R - 4 Stages  
Below Normal: 2  Normal: 1 Above Normal: 0
 Distance to Nearest Field with a History of White Mold Within the Last 2 Years  
less than 2 miles: 2  more than 2 miles: 0
Rotational Crops Include Potato, Sunflower, Soybean and/or Other Susceptible Host  
Yes: 4  No: 0
Yield Goal above 2500 lb/Acre or 42 bushels/Acre  
Yes: 2  No: 0
Variety Reaction to White Mold (based on growth habit and/or genetics)  
Susceptible: 4  Unknown: 2 Resistant: 0
Irrigation Practice/Schedule after Mid to Full Flower (R2 Growth Stage)  
more than 1/4; inch/day: 4  less than 1/4; inch/day: 2
Total Score:  

ENVIRONMENTAL THRESHOLDS (weekly) for Disease Forecast:
Temperature: Normal = average high temperature of 86 F
Moisture: Normal = 0.25 inches of rainfall
DISEASE RISK SUMMARY - If the Total Score was:

more than 15 = High Risk 10 - 15 = Moderate Risk less than 10 = Low Risk
If the susceptible variety is planted in a field with a history of disease and the total score was 10 or higher, treatment with a labeled fungicide such as Topsin M or Endura at 100% Bloom (R1 = every plant has 1 or more open blossoms) should be considered. A second application 7 days later at Full Bloom (= 7 to 10 days after R1) may be beneficial if conditions conducive to white mold continue.
Note: As with any pesticide, always read and follow instructions and precautions. Refer to the Dry Bean Growth Stage Chart, and incorporate other Integrated Pest Management approaches such as crop rotation, sanitation, certified seed, plant resistance, tillage, moderate irrigation and fertility, and timely scouting.
[Checklist adapted for Colorado and surrounding region by Dr. H. F. Schwartz, M. S. McMillan, and K. L. Otto, 6/98]