Which primary outcome resulted from the Three Sisters farming technique in pre-Columbian North America?

💡 Explanation

When beans, maize, and squash are planted together, nitrogen fixation by beans occurs because symbiotic bacteria convert atmospheric nitrogen, enriching the soil which minimizes nutrient depletion. Therefore, the practice reduced soil depletion compared to monoculture. Pest resistence, lower irrigation or lower labor hours were secondary benefits, rather than primary ones caused by fundamental biological interactions.

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