2010 Florida Citrus Pest Management Guide: Pesticide Application Technology
Most Florida citrus applications are made with air-carrier ground sprayers. These sprayers may be truck/tractor-mounted, tractor-drawn (p.t.o./ engine-driven), or self-propelled. They may be equipped with a positive or non-positive displacement pump to pressurize the spray liquid and generate spray droplets by hydraulic nozzles, air-shear nozzles, or rotary atomizers. Spray droplets are normally transported by sprayer airflow, generated with one or more axial-, centrifugal-, or cross-flow fans. The air is directed toward the canopy by a series of fixed, adjustable, or moving deflectors (oscillators). Some sprayers use a short or tall tower attachment to discharge a portion of the spray-laden air close to the upper parts of the tree canopy. Sprayers may use mechanical and/or hydraulic agitation systems.
The differences in size, shape, design features, and construction material of the sprayers could result in substantial variation in the price of the spray equipment. Nevertheless, a higher price does not necessarily mean a better sprayer or guarantee more satisfactory spray coverage. A pesticide can be expected to be effective if the 'right material' is applied, at the 'right amount', on the 'right target', at the 'right time', with the 'right sprayer', under the 'right weather' conditions. A cheap sprayer, adjusted and operated properly, may result in better pest control than a sophisticated sprayer used improperly under adverse weather conditions.