Small vegetable growers may find pesticide applications with a tractor driven sprayers impractical. Such growers may turn to hand sprayers. In a separate article, I argued that garden sprayers are not appropriate for most commercial pesticide applications.  In this article, I will discuss the use and calibration of a backpack sprayer, an excellent alternative to a garden sprayer for small growers. The remainder of this article will discuss one method of calibrating a backpack sprayer. Most pesticides are labeled for use on an area basis, typically an acre. Therefore, the first task in calibration is to measure the area to be treated. Let’s say that tomatoes are grown in a greenhouse where the production covers 30 X 100 feet = 3,000 square feet. For our staked tomato example, we will use a volume-based method of pesticide measurement. For this method: Determine the volume of water required to cover the fully-grown crop[Read More…]

Vegetable growers are familiar with pesticide labels that specify how much of a product may be applied. As commercial growers, we usually think about such instructions as telling us how much pesticide is the right amount to apply to a crop to be effective. While such an interpretation is correct, there is more to the labeled rates of a pesticide. While many researchers (including myself) are involved with experiments to try to manage pests with pesticides, others are involved in trying to determine the pesticide concentrations that may safely exist in the produce we all eat. The latter is known as the pesticide tolerance. Both efficacies of the pesticide and human safety are involved in determining the label rates and timing of each pesticide. Indeed, some pesticides are not labeled for certain crops for reasons of safety. There is mostly good news in the just released 2015 Pesticide Data Program. Each year, the USDA’s[Read More…]