Iowa biofuel supporters rallied in Nevada this weekend to voice their displeasure with potential changes to the renewable fuel standard. Members of the Iowa Renewable Fuels Association, the Iowa Corn Growers Association, biofuel manufacturers and retailers were among the approximately 170 people on hand at Crouser Farms Saturday to sign a letter to President Trump urging him to keep his promise to maintain the RFS. Trump is considering changes supporters say would greatly reduce demand for biofuels.