Updated: Jul 18, 2019
To help answer this question we referred to the University of Mississippi, which is the only federal marijuana testing facility. The terms “marijuana” and “hemp” describe varieties of the Cannabis sativa plant having high and low levels of tetrahydrocannabinol (THC) respectively. While both have medicinal value, marijuana has traditionally been abused for its psychoactive effects, while hemp has traditionally been used for industrial purposes such as seeds and fiber products. Both have been considered DEA Schedule-I controlled substances for decades in the U.S., but the 2018 Farm Bill includes amendments to the Controlled Substance Act (21 U.S.C. 812) which makes the hemp variety (with <0.3% THC content) no longer a controlled substance. Marijuana, however, remains as Schedule-I.