It's a good comparison of how metal-working has changed, to being more specialized and requiring more investment in dollars.......  and the same with agriculture.

I would also like to add that pesticides have reduced the labor costs in growing crops.  And if you know what labor costs are, you know what that means.  Before the advent and widespread use of pesticides (herbicides in particular), farmers would plow their soil, work it down 2,3,4 times, then plant their crops.  And then, they would cultivate (their corn, in particular) a couple of times during the growing season. Herbicides have enabled farmers to reduce a lot of these trips, especially the cultivators after the crop is growing. 

The use of pesticides has also been instrumental in the shift of cropping rotations.  75 years ago, a typical crop rotation was 1-2 years of corn, followed by oats, then maybe wheat or barley, and clover-timothy hay.  Today, many farmers who grow corn, no longer grow oats or clover-timothy.  The number of soybeans acres has exploded in the last 75 years, in part, I am sure, due to the use of pesticides which makes growing soybeans a lot easier.  And for the guys who grow hay - especially dairy farmers - there is more alfalfa grown than clover-timothy.  And the increased useage of alfalfa has help the cow nutritionally, to produce more milk.