Symbiotic nitrogen-fixing bacteria such as Rhizobium usually live in the root nodules of legumes (such as peas, alfalfa, and locust trees). Here they form a mutualistic relationship with the plant, producing ammonia in exchange for carbohydrates.
Tony Yardley is a national treasure living in Jacksonville, Alabama. Way back in the early 70s, I was fortunate to play in an acoustic group along with Tony called Woodfork. He was fabulous then and he just keeps getting better!
Greg Kearsley is currently the Director of Graduate Studies in the Department of Education at the University of New England, where he manages online programs with over 700 students and 40 faculty. He has written over 20 books and hundreds of technical articles on the topic of education and technology.