Peanut Pointers

If you do plant early, in part to avoid southern corn rootworm, make sure you have an effective thrips control program in place. We often need more than one insecticide treatment for thrips in the upper V-C region, especially when we plant early. This will be the case if you are using imidacloprid. This insecticide is less effective now in controlling thrips than it was five or so years ago. Peanuts are also slower growing when planted early, and we often experience higher populations of thrips in early May.

Keep in mind that we are also at greater risk for Tomato Spotted Wilt Virus when we plant early. Thrips are the vector for this virus. If planting early, in addition to effective insecticide treatments for thrips, make sure you establish four to five plants per foot of row across the entire field. This is a buffer against TSWV. Consider using Phorate/ Thimet if you plant early.

registered because it is not widespread yet; however, growers should realize quickly if herbicide-resistant populations are in their fields. Those weeds would survive following applications of effective herbicide. We can slow down the development of herbicide-resistant weed populations by rotating herbicide modes of action.

Thrips Control Options And Cautions

As we move into April, planting is just around the corner. My columns may seem repetitive; I’m certainly guilty of that. But in a short article, it’s important to get to the core elements. With peanut production, some of those have remained the same over time.

Weed control starts early with either effective tillage or burndown herbicides. Overlapping residuals play an important role in weed management. Investment early in the season is often more effective than spending the same amount of money cleaning up fields later in the season. If possible, incorporate a DNA herbicide and apply a Group 15 (usually Dual Magnum) with Valor right behind the plant. In a few weeks, you will likely need to apply a contact herbicide (Gramoxone plus Basagran) with another residual herbicide (often a Group 15). This approach takes a lot of pressure off the PPO inhibitors as we move through the remainder of the season. It also helps us control ALS-resistant weeds that are in many of our fields.

In North Carolina, we have used imidacloprid for many years. While there is concern about having more spotted wilt when this insecticide is used, in our region, the level of spotted wilt has been low enough and the resistance within our varieties good enough to have allowed this use pattern. Unfortunately, thrips control with imidacloprid has dropped dramatically over the past five years. For this reason, growers

DAVID JORDAN North Carolina State University Extension Agronomist

Based on the current southern corn rootworm index for the Virginia-Carolina region and, in particular, North Carolina, the most probable way you can minimize damage from this insect pest is to plant early. The reason this is somewhat effective is because pods tend to be more developed when this insect becomes an issue in soil in July and August. A stronger hull limits the insect’s ability to puncture pods.