While there are a number of weeds that can cause problems we will focus on a couple that conistently bring the most; kochia and waterhemp. The quick suggestion for better control is to just switch herbicide traits in next years seed and go that route. Switching traits can help but if you aren't adjusting a herbicde program to go along with these switches you will not solve the problem. To add some math to illustrate this lets say your combine is rolling though a field and you have 500 waterhemp and 500 kochia that escaped control and went to seed. The waterhemp plants produced 100,000 seeds per plant and the kochia has 20,000 seeds. So now we are looking at a potential 50,000,000 waterhemp and 10,000,000 kochia to control. Not 100% of these seeds will germinate the following year but we will stick to these numbers for this example. So if we stick to a program and hope for 95% control of these weeds (which is rated excellent in most guides) we will have 2,500,000 waterhemp and 500,000 kochia escape. Either of these number of escapes will make it tough to even see next years crop in August. But this is how weed seed bank is built up and then all at once it seems a field is lost. We went from 500 escapes which still seemed manageable to having a way bigger problem while still maintainng 95% control. The danger of just switching to a different post spraying chemical option and not adding anything else is we are relying on killing these huge numbers of weeds with just contact herbicide. This is not a formula for conistent success. The goal will have to be getting pre emerge products to attain better than 95% control and also find a better post option to pick up the remainder. We will continue to build upon these concepts in the following days here.
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Producer Marketing Manager
Director of Agronomy Technical Services