Tank Mixing and Crop Oil Concentrate Peanut Notes No. 176 2019

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I was recently asked about mixing herbicides, fungicides and insecticides and Apogee for a single application. This is a lot in the same tank. In the conversation the question of crop oil concentrate with clethodim came up and how that might affect crop injury. In the discussion we talked about concerns about getting fungicide to the base of the plant for stem rot control if we use crop oil. We don’t know how ammonium sulfate or UAN would affect fungicide performance but it is critical for Apogee to perform well. Not all clethodim formulations require crop oil but most do for consistent control. From a crop injury standpoint with crop oil and fungicides, chlorothalonil is the major concern. There have been occasional issues with foliage burn when chlorothalonil is applied with crop oil (not excessive but noticeable under some conditions.)  I don’t know of other fungicides where this is an issue. Chlorothalonil will decrease grass control by about 40%. In the end the recommendation was going to be to make two trips across the field.