It is likely that there will be increased interest in preharvest herbicide application as a harvest aid in wheat. The following is a review of the herbicide options and some points to consider in making a decision. Therefore, this practice is generally not recommended. Check the herbicide label for details. Application can be made after the small grain has reached the hard dough stage.
Earlier application carries a serious risk of crop injury.
The best choice between the amine and ester form of 2,4-D will depend upon the individual situation. The ester will be more effective on the weeds, however, the risk of off-target injury from volatilization must be considered. To minimize this problem, the ester form of 2,4-D should not be used if the temperature is expected to exceed 80oF within one day of treatment. The amine form of 2,4-D will be less effective but does not have the risk of volatilization. Both herbicides can cause off-target injury from spray particle drift.