Smart sprayers are on-off affair
Some orchard sprayers used by fruit growers are gaining intelligence; and the smarter they get, the more money they save — if the farmers can just afford them.
This cerebral economic conundrum was embraced in the current issue of California Agriculture, a peer-reviewed quarterly journal from the University of California. The article also explored the benefits to the environment when "smart" spray equipment is used.
In this case, "smart" means a sprayer that is smart enough to shut itself off between trees or when a tree is missing. After all, trees and foliage are the targets of sprayers that dispense pesticides, not the soil or the air.
Several studies included in the article were undertaken in orchards in Chico, Oroville and Modesto, each examining a different aspect of the efficiency of smart sprayers. The patent on the novel technology recently expired, so other manufacturers will likely begin building equipment with the feature. Upgrading or retrofitting older, less-educated sprayers with the technology now is also an option.
UC Davis experts Durham Giles and Daniel Downey joined Franz Niederholzer, UC Cooperative Extension farm adviser for Sutter and Yuba counties, and Parry Klassen, executive director of the Coalition for Urban/Rural Environmental Stewardship, to author the article, and each participated in one or all of the studies.
Giles, a professor in the Department of Biological and Agricultural Engineering, and Downey, associate project engineer in the same department, began studying the equipment soon after its introduction in the 1980s.
The authors reported that reduction of applied spray materials varies, based on the type of orchard by 15 gallons per acre in mature prunes, 22 gallons in almonds, and in a younger prune orchard, 40 gallons per acre. That amounts to substantial savings for the orchard owners.
Further savings were recorded because the spray tank required less frequent filling by support equipment and because spraying an orchard required less time with the on-and-off smartness built in. The estimates of pesticide costs were extrapolated from several UC Cooperative Extension publications.
From an environmental standpoint, the runoff of chemicals from a simulated rainfall in the Oroville prune orchard was reduced from 976 gallons to 854 gallons. Klassen's organization has encouraged growers of orchard crops to reduce or prevent chemical runoff from their orchards and fields.
Because a smart sprayer operates for less time per acre, it can significantly decrease the amount of volatile organic compounds (VOCs) released, thereby reducing the potential for smog, reduced visibility and inhalation by humans, livestock and other animals and living creatures.
Measuring the amount of chemical compounds released by the sprayers was done by suspending small cylinders with fiber filters from target trees, and laying out sensitive ceramic tiles on the orchard floors.
Just like education for humans, the smart sprayers' degrees don't come cheap, either as new units or retrofits of older equipment.
Durand-Wayland, a Georgia manufacturer, supplied the smart sprayer that was used in the tests reported in the article. The company, which holds the original patent along with a trademark for the name "Smart Sprayer," has pioneered development and sales of the automatic stop/start feature on the powerful, high-rpm spray equipment used in orchards.
The researchers are not promising that educated sprayers will solve all the issues that go with annual orchard soak-downs. It's a little like passing out of the fourth grade, knowing that several further grade progressions will be necessary before education can be considered complete.
Orchardists will be hoping that the teachers along the way will be likeable and given to easy grading.
CONTACT Don Curlee at agwriter1@sbcglobal.net
