Wisconsin Winter Wheat Disease Update – May 20

Winter wheat plots were examined this week by my graduate student, Brian Mueller, near Sharon, WI (far southern Wisconsin). Flag leaves had recently emerged and wheat looked very good in this location. No rust or other diseases were observed in this part of the state. Further north, we examined winter wheat fields near Arlington, WI.  No rust or other diseases were observed here either. Many varieties had fully emerged flag leaves and will soon be in the ‘boot’ stage. Now is the time to consider fungicide applications for protecting flag leaves. Also, growers in the southern and south central portion of Wisconsin, should start watching the weather and checking the Fusarium head blight (scab) Prediction Center frequently to make a decision about applying fungicides to protect wheat against scab. Remember, the best time to apply fungicide to control scab is at anthesis and up to 5-7 days after anthesis.  However, weather conditions prior to anthesis can affect the level of risk for scab, so start making weighing your options now. Remember, to scout, scout, scout!