Peanut Grower Magazine Article for July 2015
Many of the foundational decisions have been made for the peanut crop in the V-C region by the time July arrives.
Weeds, thrips, and gypsum have been taken care of by this point, although there will be weed escapes in many fields running through July and August. Annual grasses that escape can be a challenge even when they emerge later in the season. A well-timed application of a graminicide will be worth the expense.
Fall armyworms and corn earworms and possibly beet armyworms can be an issue and populations need to be kept in check. Careful identification and insecticide choice are important when making management decisions for these insects. While this column will come out on the end of applications for rootworms, there may be some fields that are at risk. Take a look at the risk index Ames and Rick developed and treat accordingly.
Always be mindful that spider mites can be an issue and applying as few insecticides as possible can minimize issues with mites. Treating patches of mites as they first begin showing up is a good way to manage this pest in many fields. Leave ditches and border areas undisturbed as farming a “little ugly” can minimize movement of mites into fields. Try not travel across fields too often as mites can hitch a ride and spread quickly.
If we run into a situation where gypsum and insecticide for rootworms is delayed (excessive rainfall for example) these inputs can still be valuable when applied all the way through the month of July. Certainly the major focus in July will be disease management.
With our improved genetics, we can be successful with a 4-spray program for leaf spot and stem rot in many fields. Starting and ending with chlorothalonil alone or in mixture serves us well, with the 2 or 3 sprays in the middle being very flexible in what is used. Always rotate chemistry to minimize resistance development. There will be a lot of questions about mixing plant protection products. Read product labels, check with other farmers, consultants and extension/research folks to see what can and cannot be applied together. There are just under a zillion possible combinations and we just don’t want any major surprises.
For the upper V-C, keep in mind that Sclerotinia blight is still a major player in the region. A well-timed early spray often brings in the most dividends. There are certainly some options and a number of good resources to make your selection. Production guides in NC and VA have good information on what programs to pursue for this disease and others. And don’t forget boron and manganese, especially boron on sandy fields.
Article first appeared as North Carolina Peanut Note (PNNC-2015-044)