Which application method is associated with aerial application?

Aerial application is a specific method of pesticide application that involves the use of aircraft to distribute chemicals over a large area. This method is particularly effective for treating expansive aquatic environments where other methods may be cumbersome or inefficient. Aerial application allows for uniform coverage and can reach areas that are difficult to access via ground equipment, making it suitable for managing aquatic pests over lakes, rivers, and other water bodies.

The other methods listed are not associated with aerial application. Handgun spraying of surfaces typically refers to ground-level treatments utilizing handheld sprayers, while subsurface injections and bottom placement focus on delivering materials directly beneath the water's surface. Such methods generally require more controlled approaches and are utilized for specific applications rather than for widespread coverage that aerial application provides. Thus, aerial applications remain the distinct method identified in this context.