In many conventional production systems, the search for economic return and high productivity makes herbicide application a common and necessary practice. One of the observable examples is in pasture rearing systems, which present the need for weed control with auxin herbicides, such as Picloram. However, application of this herbicide can lead to problems such as leaching and contamination of waterways and groundwater. Therefore, the search for information about the leaching processes is necessary to understand the dynamics of the application of these pesticides in the field.