We hear the term "sustainable" a LOT these days. But what does it really mean when it's applied to agriculture? Joshua Earl Arnold, professor of sustainable agriculture at Warren Wilson College, explains.  Press play to learn more about:    Socioeconomic to biophysical challenges faced by urban farmers Sustainable agriculture's reliance on ecosystem services, including insect and plant activity and soil-building, and how the ecosystem is disrupted in urban farming   What the lack of agricultural subsidies for irrigation means for urban farmers How nutrient cycling on urban farms works The issue of security of tenure for urban farmers and how parklands, schools, and faith-based communities are helping Interested in learning more? Want to learn more about Joshua and his outlook on sustainable agriculture? Click here now! Episode also available on Apple Podcast: http://apple.co/30PvU9C