By Paul D. Esker
Recently, a supplemental label for CarambaTM fungicide was approved for use in all corn types. CarambaTM is a group 3 fungicide with an active ingredient of metaconazole. The targeted corn diseases include eyespot, gray leaf spot, northern corn leaf blight, northern corn leaf spot, rust, southern corn leaf blight, southern rust, and yellow leaf blight, although not all of these diseases commonly occur in Pennsylvania.
The product use rate is from 10 to 14 fluid ounces per acre, with a maximum product rate per season of 60 fluid ounces per acre, which is equivalent to six applications at 10 ounces per acre or four at 14 ounces per acre. It is best to use CarambaTM prior to disease development and if conditions for disease warrant, applications should be made on a 7- to 14-day window, although it is important to note that the maximum number of sequential applications to reduce the risk of fungicide resistance is two for this product or other demethylation inhibitor (group 3) fungicide.
The preharvest interval (PHI) is 20 days for field corn grain, field corn stover, pop corn grain, pop corn stover, and sweet corn stover. The PHI is seven days for field corn forage/silage, pop corn forage, sweet corn forage, sweet corn kernel, and seed production corn (all types). There are no livestock feeding restrictions.