(Olympia, WA)  --  A bill that would legalize hemp farming in Washington is headed to the full Senate.  Senate Bill 6206 would license hemp farmers, control the seed supply, and regulate cultivated plants to ensure low levels of THC, the psychoactive substance in marijuana.  The measure would also provide for a study by Washington State University to explore the commercial potential for hemp and whether it could spread diseases harmful to other crops.  The state Agriculture Department aims to have the program ready for the 2017 growing season, should the bill pass.