A row crop farm will plant 300 acres in one to three days, harvest it in one to three days, spray it in a half a day.  That's just the reality of the industry at this point in time.  50 years ago, farmers could only buy tractors with 50-100 hp.  Today, we can purchase 4-500 hp tractors.  50 years ago, combines also had 50-100 hp.  Today they have 300.  If the farmers 50 years ago could have bought machinery with the capabilities we can today, they would have.  It just wasn't available, because the 'off-farm' portion of the country had not had time to develop it for us.  50 years ago, the country had only moved about 1 generation away from subsistence agriculture.  Lots more people and talent were being expended simply making enough food to feed everyone.  Today, thanks to the advances made by those who were freed up from having to toil constantly to produce food, we don't have to work nearly as many hours to produce the food we eat. 

50 years ago, a construction worker didn't have to move nearly as many yards of dirt to make a living for a year, either.  Moving dirt was a lot more expensive because it took a lot more work....just like growing food was more expensive because it took more work.