Corn fungicides have been going on a good number of acres in areas that have aerial application options.  We have more May planted corn this season that is tasseling now and pretty good soil moisture.  We typically have more disease pressure in May planted corn although reports of Gray Leaf Spot and other diseases have been sporadic in rotated ground.  A better return on your money is most likely where some disease is evident, yield potential is decent and the hybrid has shown more of a response to a fungicide based on field testing.  We have fungicide response data generated at Milan for early and medium hybrids included in the County Standardized Testing program for 2009 and 2010.  (There was an issue with our link to the 2010 data but that is fixed and all information should be accessible).  In addition to sometimes improving yield, fungicides can keep the field greener later and help with standability which may be beneficial for difficult to get to areas that have to wait on a combine. 

• Tassels emerge approximately 60 days after planting.  Silks emerge soon after and fungicide should be applied as early into silking as practical.   A higher water volume with aerial applications is preferred and Dr. Newman recommends including a spreader/sticker with his sprays. 
• We do not get strong yield responses with all hybrids.  Some hybrids do not yield enough extra corn to even pay for the cost of the treatment.  Response varies with susceptibility to disease, disease pressure and other factors that are not well understood.  Agventure R7938, Dairyland 7313, Dekalb DKC 62-97, DynaGro 57V40, Mycogen 2V732 and Wyffels W6871 were the early hybrids with close to 8+ bushels response to a Quilt Excel treatment in a dryland field with last year’s heat and lower moisture environment.  Medium hybrids responded less as a group compared to the early maturity hybrids.  AgVenture RL8042, Dairyland 7214Q,  DynaGro V5683, NK N77P-3000GT, and Wyffels W8681 were the better responders in that group in 2010.
• Fungicide response data for other hybrids can be found at utcrops.com under corn disease information.