The glyphosphates used to kill weeds, also kills the microbes which are needed to convert that N into a plant usable form...
The crop rotation helps to break the pest cycle.
I don't have a farming background but live in a predominately farming county. I need to learn more about what the farmers do and why so I can spar with them a little better.
Around here, it's a bean and corn rotation year after year after year. I was surprised a few weeks ago when one of the farmers mentioned that he had to fertilize before he could plant his corn. I always thought that the beans replaced the nitrogen. He said the beans do but they use it for themselves, therefore, he needs to fertilize... What the heck is the purpose of rotation then? I thought I had read that legumes have nodes that leave nitrogen or am I confused with something else?
Last night I was told the corn stalks left on the field will raise the acidity and so every few years, they need to lime the field. Is that because no "greens' ever get left? My favorite sparing partner said that my way of composting in place, will also eventually raise the acidity in my beds.
I really need to learn as much as I can about what they do and why, so I can sound half way intelligent when I'm combating their practices.