Earlier quoted context omitted.
Drones do not seem like a logical step for me. I'm not a laser expert, but seems like the energy storage needed to kill hundreds to thousands of something with light is heavier than flying would realistically allow. Wheels and tracks are what farming is built around, no need to literally reinvent the wheel here.
Completely agree about flying: but I wonder about the wheel. A spider-carriage walking robot which could step around the valuable plants, climb steeper hills, and wouldn't dictate a row-and-plow approach to agriculture, that could be pretty compelling. Less soil compaction, more flexibility, could work inside forested regions as well. It has potential.
It's not just the robot though, it's the millions or tens of millions of dollars of wheeled or tracked equipment he already has.