> That's why people had to leave fields fallow, to allow nitrogen fixing plants (such as clover) to grow and then compost in-place Leaving fields fallow does a

> That's why people had to leave fields fallow, to allow nitrogen fixing plants (such as clover) to grow and then compost in-place Leaving fields fallow does allow the land to recover and can reduce certain pests and diseases. However, the primary purpose of leaving fields fallow historically wasn't necessarily for nitrogen-fixing plants to grow. That said, some traditional farming systems deliberately planted nitrogen-fixing cover crops, like clover, in rotation with other crops to replenish soil nitrogen. And let's not forget about nitrogen fixing trees. > an extremely poor efficiency of biological nitrogen fixation Biological nitrogen fixation may not be as immediately effective or efficient as directly applying synthetic nitrogen fertilizers, but it's a natural process that has sustained ecosystems for millennia. To say it has "extremely poor efficiency" might be an overgeneralization. In sustainable agriculture, the efficiency of nitrogen-fixing plants isn't solely measured by the speed or volume of nitrogen delivery but also by the myriad of other benefits they provide, such as improving soil structure, suppressing weeds, and promoting beneficial soil microbes. > It's a wonder that it works at all Biological nitrogen fixation is a well-established and crucial ecological process.