There is more than that. He needs to decide which corn seed to plant (he is behind here - seed companies run sales if you order in October for delivery in mid march). He needs to decide what fertilizer to apply, and when. He needs to monitor the crop - he might or might not need to buy and apply a fungicide. He needs to decide when to harvest - too early and he pays a lot of money to dry the corn (and likely money to someone you hired to work who doesn't do anything), but too late and a storm can blow the corn off the cob... Those are just a few of the things a farmer needs to figure out that the AI would need to do (but will it)