Hemp and marijuana alike, come from the same plant family, cannabis sativa. The main difference between the two is their levels of tetrahydrocannabinol (THC) - the federally illegal, psychotropic cannabinoid. According to the Agriculture Act of 2014, American legislation describes legal hemp plants as containing less than 0.3 percent THC. The Hemp Farming Act of 2018 was a law proposed to remove hemp from Schedule I controlled substances and making it an ordinary agricultural commodity. Its provisions were incorporated into the 2018 United States farm bill that was signed into law on December 20, 2018.