There are relatively few herbicides registered for use in lettuce. In fact, the principle 3 herbicides used, Kerb, Balan and Prefar, were all first registered almost 50 years ago. Additionally, lettuce is planted starting in the summer when summer annual and perennial weeds are a problem and through the winter when winter annual weeds are a problem. This larger number of potential weed problems combined with the limited number of available herbicides, makes it necessary to try to kill as many weeds as possible prior to planting.

Almost any herbicide registered for fallow conditions can be used prior to planting lettuce as long as the preplant and preharvest intervals are observed. The herbicides most commonly used for this purpose all have a 0 preplant or preharvest interval. ET is 1 day and Metam Sodium is 14 days preplant. For more information click on the following link to see the table: Herbicides for Ground Preparation in Lettuce.

To contact Barry Tickes go to: btickes@ag.arizona.edu.

For questions or comments on any of the topics please contact Marco Pena at the Yuma Agricultural Center.
College of Agriculture, The University of Arizona, Tucson, AZ.