Which application method is effective on lower portions of brush or small trees and can be applied anytime except when there is snow on the ground?

The basal application method is specifically designed for effectively targeting the lower portions of brush or small trees. This technique involves applying a herbicide to the lower trunk or base of the plant, which allows for absorption through the plant's bark and into the vascular system. This method is particularly useful for controlling woody plants because it minimizes damage to surrounding desirable vegetation and maximizes herbicide uptake.

Timing is also crucial in the effectiveness of basal applications. They can be performed any time of the year, excluding conditions where snow is covering the ground. Snow can hinder both the application's effectiveness and the herbicide's ability to penetrate through to the plant.

In contrast, band and broadcast applications typically cover larger areas and are not specifically aimed at the bases of brush or trees. Band application treats only a specific section or strip of ground, while broadcast application covers a wide area indiscriminately. Physical incompatibility refers to the inability of certain substances to mix or function together properly, which does not apply to application methods directly.