As you travel over your field with your herbicide this season, you may be considering adding a fungicide to that pass. If so, there are a few things to think about. In general, early fungicide applications on corn (V5-V7) have not been shown to provide much yield benefit over no treatment (average is +1 bushel per acre). In repeated trials across the country, we see the best opportunity for yield response with a treatment at tassel (average: +8 bushels per acre). However, there are some situations in which an early treatment may be more economical.

Corn is all over the board in terms of growth and development, ranging from V6 to R2. Late-planted fields are usually at greater risk for foliar disease development, and reports coming in indicate that gray leaf spot is already present on the lower leaves in some areas.