My vague recollection leads me to https://en.wikipedia.org/wiki/Peak_phosphorus https://en.wikipedia.org/wiki/Peak_phosphorus While they can pump in nitrogen a

My vague recollection leads me to https://en.wikipedia.org/wiki/Peak_phosphorus https://en.wikipedia.org/wiki/Peak_phosphorus While they can pump in nitrogen and phosphorus, they can get away with trashing the soil as much as they want. But if phosphorus becomes scarce they'll be suddenly left with ruined soil and no cost-effective work-around.