Farmers from 17 southern states supply more than a third of the world’s cotton and bring in $7 billion a year. But brands and retailers — cotton’s customers — are getting picky about how their cotton is produced. They want to assure their customers that farmers care about the environment. The U.S. Cotton Trust Protocol gives farmers a way to measure and improve soil carbon, greenhouse gas emissions, water use and energy use, among other things. Dr. Andy Jordan, who helped write the protocol, explains how it works to Field Work hosts Zach Johnson and Mitchell Hora. They also discuss how the protocol might be adapted to other crops.

Read more: Five questions about the U.S. Cotton Trust Protocol