Issue No. 9, Article 3/May 23, 2008
Insecticides and Replanting Decisions
With wet weather and cool soils affecting corn emergence, some corn growers have decided to replant or are contemplating it. When considering such a decision, make certain you consider the agronomic guidelines. From an insect management perspective, however, it's important to think about the possibilities for applying a soil insecticide during replanting. Many soil insecticide labels have restrictions related to the maximum pounds of a given insecticide that can be applied in one season, which often is the same as the pounds per acre for 30-inch rows. Some labels also suggest that the product can be applied only once per season, whereas others allow for a second application if replanting is necessary. Following are the indications for the most commonly used soil insecticides:
- Aztec 2.1% Granular--maximum of 7.3 lb per acre per season
- Aztec 4.67G--maximum of 3.27 lb per acre per season
- Counter 15G--maximum of 8.7 lb per acre per season
- Capture LFR--Do not apply more than 0.1 lb active per acre per season as an at-plant application. Do not apply more than 0.3 lb active per acre per season including at-plant plus foliar applications of bifenthrin products.
- Force 3G--Use only once per crop.
- Fortress 2.5G or 5G--Do not make more than one application per year.
- Lorsban-4E--Do not apply more than 6 pt (3 lb ai chlorpyrifos) per acre per season.
- Lorsban 15G--Retreatment with a second soil application is allowed under replant situations due to loss of crop during establishment. Do not apply more than a total of 3 lb active ingredient of chlorpyrifos per acre per season.
The labels of soil insecticides typically do not prohibit the use of other soil insecticides with different active ingredients if corn is replanted in a field where a soil insecticide was applied during the first planting. There don't seem to be any restrictions for replanting situations with Poncho- or Cruiser-treated seed.--Kevin Steffey