Back when I was in the elementary, we were taught how to cultivate plots and plant vegetables. We would later bring home the vegetables we planted. As early as those days, we were taught to bury deep down in the plot the fallen leaves of vegetables. The object was to let the soil reabsorb the nitrogen and minimize costs on fertilizers.
We were also taught how to make compost pits. In high school, a very avid teacher even required us to have a compost pit at home. At the end of the school year, he literally went around to check who did the assignment. Again, the motivation was to save on costs.
The ideal of recycling things within the farm was already implanted. This was when in the early 70s. There was no "green" movement then.
The one thing, it seems, that has changed from then to now is the motivation: from saving costs to saving Costs, in capital "C." The Cost is the Planet Earth itself.
I get this feeling that the "green" things we talk about is simply a wake up call that everything "instant" has its repercussions. You see, urea works faster than compost. Insecticides and pesticides work faster than developing an organic environment. Driving a car is faster than riding a horse.
What the "green" movement is hammering into our collective consciousness is the need to include in all our calculations all those things that we usually take for granted as inexhaustible: earth, wind, air and fire. We are in the age of realizing that there is an edge somewhere in the horizon where the entire earth can actually fall to oblivion if we are not careful.