How much people does it take to harvest and process manually a hundred acres ? Scale that to the average Canadian farm size of 780 acres. Today, a crew of a few people (one driver for the harvester, one support tractor + trailer, plus a pair of dump truck) can harvest and process that much in a 40h week. Now, a diesel engine in a truck in pretty much the same as the diesel engine in the harvester, so job redundancy, the mechanics shop has now 3 employee instead of 2. At worst, you get a few more people in a fab shop when the farmer cannot hack something up, but that pretty much stop here. So really, you can harvest a complete farm with 12 people (including shared support). That doesn't even compare to the hundreds of jobs cut when mechanization was introduced.