As spray gun applications use a more dilute spray mix, this type of application must thoroughly wet the foliage, stem and root collar. Brush should be treated after foliage is well developed in spring or early summer. To ensure thorough coverage and minimize drift, brush to be treated should be less than 2.5 m tall. For broadleaf herbaceous weeds, apply broadcast in spring or early summer after growth begins. Residual Activity Soil residue carryover into the year following application is minimal when applied at recommended rates.
Degradation is most rapid under warm, humid conditions.
Because small residues of picloram in soil can be phytotoxic to crops such as soybeans, tobacco, tomatoes, potatoes, grapes and many desirable ornamental plants, picloram may not be applied to land used, or land that may be used, for the production of agricultural and horticultural crops. This information is provided as a public service, but we cannot guarantee that the information is current or accurate. Readers should verify the information before acting on it.