“We are going to run out of money before we run out of pigweed” one veteran West Tennessee weed manager stated last week. That really sums up where we are now in many fields. These are fields where frequent rain has made timely POST applications very hard to get done or in fields where timely applications were made but herbicide resistance limited the control. Fortunately, that does not describe every field as many are relatively clean.  Overall this year though, it is clear we will have to live with Palmer amaranth in more fields than we would like.

The limited money to pigweed ratio also comes into play on the many prevented plant fields that were either never planted this year or that were planted and then lost to flooding. The question is what is the most economical strategy to not allow weeds to go to seed in these fields?

An economical path would be to till up the fields to take out the weeds that are up and then spray a herbicide to provide residual control.  A relatively inexpensive herbicide that could fit the bill here would be Valor. According to the label, the rates for non-crop areas goes up to 6 to 12 ozs/A. Those rates with crop oil would likely provide pretty good burndown on fields that cannot be tilled. These higher use rates might also be overkill and burn up what is left of the budget. Lower rates in the 3 to 4 ozs/A range should provide enough residual control to get to September. The shorter day length and typical dry weather of September typically hinders the emergence of most summer annual weeds.

If wheat is the next crop to be planted into the field then most any residual herbicide is not an option as they can impact wheat emergence.  The lone exception could be Valor as the plant back to wheat after a 3 oz/A application is 2 months. Since it is already mid-July,  tillage if possible may be the best option followed by Gramoxone as a burndown in September.