By Louis Sutton
Regional Product Manager | Agronomy Lead

(Photo courtesy of University of Nebraska-Lincoln.)

Time seems to be in short supply, especially right now as farmers are busy with planting, last-minute fertilizations, and field prep. In the midst of all the chaos, it can be easy to lose track of the fields that have been planted and what they need as they develop, emerge and grow.

The first step is applying pre-emergence herbicides or doing a burndown. Once the crop emerges, it’s time to tackle the next item on today’s to-do list. Next thing you know, weeds begin sprouting throughout your field. Most years, this crop of weeds continues growing and spreading in the field until the corn plants surpass the V7 stage of development, sometimes even longer. By now, the weeds have reduced the yield by competing with the corn plants during the critical yield-determining stages. The weeds have used up the applied fertilizer and moisture that was intended for – and needed by – the corn. Weeds also competed with corn for sunlight and space to grow in. All these factors add up to reduced yields, ultimately lowering the return on your investment. I know in many areas, the weeds are not to this point in development, but in some areas, they are. So, for some, this could be a warning, and for others, a call to action.

(Photo courtesy of University of Arkansas.)

With spring rains delaying planting completion and slowing down spraying, many weeds may be nearing or have already outgrown the height listed on the label. When weeds are sprayed and not fully controlled, it leads to herbicide resistance. Some farmers are choosing herbicides and spraying beyond the labeled time, which leads to the need for expensive rescue treatments. You may have heard the adage, “Spray when the weeds are soda-can tall,” (or pop can, depending on where you live). The truth behind that adage allows you to arrange the weeds to be sprayed before they reach six inches tall. But remember, if the corn has reached V7, you have already lost some yield. With an expected drought, weeds will harden off and become even more difficult to kill. Don’t be that guy that A) waits until the field is a carpet of weeds to act or B) is trying to kill weeds that are two feet tall. Plan for success and stick to the plan.

So, if you want to maximize your profits, you need to prioritize field scouting on a regular basis, with no excuses. If you can’t get this done, call your AgVenture Yield Specialist and ask for some help. I would suggest that you spray when the weeds are two to three inches tall. This should help control the weeds and add a good post-emergence residue product to the spray mix. Make sure to get this done before the corn reaches the V5 stage of development. Always read and follow all product labels – they put requirements on the label for a reason! Based on the Maximum Profit System strategy for your operation, you and your AYS should work together to select the best crop protection products for your area. If your AYS cannot answer your questions, they can always reach out to me or another member of the AgVenture team for additional assistance.