Farmers are increasingly deploying drones to spray their fields as growers look for alternatives to tight labor markets and heavy machinery that can knock over crops.

While traditional land-based tractors and crop-dusting airplanes can still deliver larger amounts of herbicides or other crop chemicals, drones hovering over fields are less disruptive to developing plants during the growing season.

For Rantizo LLC, an Iowa-based startup providing drone equipment and training, flights more than tripled last year over some 92,000 acres. A few years ago, the company’s flights were limited to about a single acre in an hour. Now, it can cover six to 26 acres in that time.

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