OAKVILLE, Calif. (AP) — Small, unmanned helicopters are being tested by University of California, Davis researchers for use in pesticide spraying at farms and vineyards in Napa Valley.

A team of agricultural engineers flew a 200-pound RMax helicopter built by Yamaha over the university’s research vineyard Wednesday in Oakville, according to the Sacramento Bee (http://bit.ly/1b8bQec).