Late Season Burndown Options for Cotton. The call of the last week has been what should my burndown strategy be with planting time upon us? A number of these calls have been from folks who have moved to higher rates of dicamba to manage horseweed. Remember, for dicamba rates higher than 8 oz/A, the waiting period to plant cotton is 30 days.  With cotton planting time just around the corner dropping back to the 8 oz dicamba rate would be a good option.  The waiting period for 8 oz/A of dicamba to plant cotton is 14 days and an inch of rainfall.  Due to the light horseweed pressure this year, 8 oz of dicamba should do a good enough job in most cases.  

For those that are using Reflex as a residual for pigweed, you might consider tankmixing the Reflex in with the dicamba at the 14 days before planting timing.  If there is a delay in planting then plan to use Cotoran or Caparol at 32 oz/A rate Pre.  That way there are two modes of action which should help alleviate Palmer developing resistance to Reflex. On top of that you are assured to start clean which is a must.

One final thought is that it is critical to start clean.  If the burndown is delayed to near planting or Palmer has started to emerge near planting, the weeds must be controlled.  The best bet is Gramoxone Inteon (paraquat) as suggested below:

Gramoxone Inteon 40 to 48 oz/A + 0.25% NIS + Caparol 32 oz/A or Cotoran 32 oz/A  

Management Considerations:
a. This application can be applied right up to planting.
b. Gramoxone Inteon rates below 40 oz/A will not provide as consistent control of Palmer amaranth or horseweed as higher rates.
c. For larger horseweed or Palmer amaranth (>6”) use 48 oz/A of Gramoxone Inteon.
d. Apply at 15 gallons of water per acre with flat fan nozzles.