Column for Peanut Grower Magazine in July (This Is a Little Early)
July brings us to a focus on disease control programs from leaf spot and stem rot perspectives. There are a lot of ways to get to a good place by the end of the season. In North Carolina the first spray is generally applied at R3 with follow up sprays spaced 2 weeks apart or applied based on the advisory system. A key to maintaining fungicides in the future is a good resistance management program, and this always involves rotation of modes of action. In the V-C we also deal with Sclerotinia blight, and good options are available there as well.
Growers are also correcting micronutrient deficiencies and these include boron and manganese. In terms of gypsum, if weather patterns happen to be like 2013 there might be challenges to getting gypsum out. At the time of writing this column the weather in July is an unknown. But to quote Astor Perry, former peanut specialist at NCSU (this is second hand from Gene Sullivan, also a former extension specialist at NCSU,) Dr. Perry stated that “he believed he would put gypsum out after peanuts were harvested if he had to.” The point is that gypsum is critical for Virginia market types and even delayed applications provide value no matter what the delay is caused by. Aside from disease, there will also be insect pests that cause problems, especially foliage feeders. Check local thresholds for these with a knowledge of resistance in the population. Some weeds will have slipped through and cleanup will be needed there as well. The potential for mixing pesticides and other products (fertilizers, Apogee, etc.) exists. Use some caution when mixing, making sure efficacy, crop safety and settling of materials in the tank are considered.
If anyone notices a nitrogen deficiency, get ammonium sulfate out as soon as possible because time is the enemy late in the season. You also can’t dabble around with the rate as it will take 120 pounds actual N to correct a real nitrogen deficiency. For Apogee, apply at 50% row closure and then repeat 2 to 3 weeks later. Applying Apogee with spray grade ammonium sulfate or with liquid nitrogen in the spray solution is critical for adequate performance of this product. There is a little nuance to all of the suggestions and comments above. Check with Extension folks, consultants, reputable Ag business people, and other farmers when making these decisions.
Article first appeared as North Carolina Peanut Note (PNNC-2014-070)