When applying chemicals to crops, where the chemical is delivered is sometimes more important than how much is delivered. A team of Agricultural Research Service and university scientists has developed a new laser-guided spraying system that controls spray outputs. “Conventional spray application technology requires excessive amounts of pesticide to achieve effective pest control in floral, nursery, orchard, and other specialty crops,” says ARS agricultural engineer Heping Zhu. “This challenge is now overcome by our automated, variable-rate, air-assisted, precision sprayer.
The system has many parts that have to work together with precision. “It integrates a high-speed laser-scanning sensor in conjunction with a Doppler radar travel-speed sensor, an automatic nozzle-flow-rate controller, an embedded computer, a touch screen, a manual switch box, and four five-port nozzle manifolds on each side of the sprayer,” says Zhu.
The team conducted field trials to assess the technology’s performance in six commercial nurseries in Ohio, Oregon, and Tennessee. “Our field experiments showed that the precision sprayer, when compared to conventional sprayers with best pest management practices, consistently sprayed the correct amount of chemicals. It also deposited the spray more uniformly on the targets, even at different growth stages,” says Zhu.
“Pest control with the new sprayer was comparable to that of conventional sprayers, but the new sprayer reduced average pesticide use between 46 and 68 percent, with an average pesticide cost savings of $230 per acre for ornamental nurseries,” he says.
“This new precision spraying system has significantly advanced the technology for efficient variable-rate pesticide applications, and it offers an environmentally responsible approach to controlling insects and diseases,” says Zhu.
Zhu and his colleagues received a USDA National Institute of Food and Agriculture grant to develop the system. The technology and performance evaluations were described in several papers in the journal Transactions of the ASABE.
“Laser-Guided Crop Sprayer” was published in the February 2016 issue of AgResearchMagazine.