Autonomous Robots Plant, Tend, and Harvest Entire Crop of Barley
The amount of labor involved in grain crops like barley per dollar of output is minimal already - the guy running the tractor/combine/etc is mostly making sure nothing breaks and keeping an eye on things (which is important when you're operating $N00,000 worth of heavy equipment on open ground).  You do need guys, however, for when things do go wrong, and for all the other farm tasks (equipment maintenance, fencing, maintaining irrigation, and so on).