'Nitrogen fixer' refers to plants that host symbiotic microorganisms in nodules among their roots that "fix" nitrogen gas from the air by combining it with carbon to make amino acids and related molecules. Includes most members of the pea or bean family (Fabaceae), plus certain other species.
- Toby Hemenway, "Gaia's Garden - A Guide to Home-Scale Permaculture ". 2nd. White River Junction, Vermont: Chelsea Green Publishing, 2009. Print. p. 287. Amazon.com
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