Reintroducing Hemp NPR's David Welna reports on efforts to reintroduce hemp as a legal farm crop in the United States. The Drug Enforcement Agency still considers hemp to be marijuana. Technically, both hemp and marijuana plants are classified as 'cannibis sativa'. But hemp has almost none of the pyscho-active ingredient found in marijuana. Hemp has many uses, mainly as a fiber. Its cultivation goes back to colonial times.