Defining Hemp: A Fact Sheet
Congressional Research Service 3
Statutory Definition and Regulatory Oversight
Congress expanded the definition for hemp in the 2018 farm bill (amending the 2014 farm bill
definition of industrial hemp), further distinguishing hemp and marijuana under U.S. law. Hemp
is codified in Section 297A of the Agricultural Marketing Act of 1946 (AMA, 7 U.S.C. 1621 et
seq.) as:
the plant Cannabis sativa L. and any part of that plant, including the seeds thereof and all
derivatives, extracts, cannabinoids, isomers, acids, salts, and salts of isomers, whether
growing or not, with a delta-9 tetrahydrocannabinol concentration of not more than 0.3
percent on a dry weight basis.
As defined in statute, hemp must contain no more than a 0.3% concentration of delta-9
tetrahydrocannabinol (delta-9 THC)—marijuana’s primary psychoactive chemical. In general, a
level of about 1% THC is considered the threshold for cannabis to have a psychotropic effect or
an intoxicating potential.
Some suggest that cannabis with a THC level of greater than 1% be
considered a drug varietal (e.g., marijuana),
with some suggesting that marijuana plants often
have a THC level of 5% or more.
In the United States, hemp varieties or cultivars having less
than 0.3% THC may be cultivated under USDA-approved license as hemp, while plant varieties
or cultivars having higher amounts of THC may not be cultivated as they are considered to have
too high a potential for drug use.
By contrast, marijuana (or “marihuana,” as it is spelled in the older statutes) is more broadly
defined in the CSA and does not specify a permissible limit for THC or any other cannabinoid:
(16) The term “marihuana” means all parts of the plant Cannabis sativa L., whether
growing or not; the seeds thereof; the resin extracted from any part of such plant; and every
compound, manufacture, salt, derivative, mixture, or preparation of such plant, its seeds or
resin. Such term does not include the mature stalks of such plant, fiber produced from such
stalks, oil or cake made from the seeds of such plant, any other compound, manufacture,
salt, derivative, mixture, or preparation of such mature stalks (except the resin extracted
therefrom), fiber, oil, or cake, or the sterilized seed of such plant which is incapable of
germination.
Marijuana is a Schedule I controlled substance under federal law, and, as such, the unauthorized
manufacture, distribution, dispensation, and possession of marijuana is prohibited.
A definition of hemp was originally established in the 2014 farm bill and amended by the 2018 farm bill (P.L. 115-
334, §10113). The 2014 farm bill defined industrial hemp to mean “the plant Cannabis sativa L. and any part of such
plant, whether growing or not, with a delta-9 tetrahydrocannabinol concentration of not more than 0.3 percent on a dry
weight basis” (7 U.S.C. §5940(b)(2)).
See, for example, E. Small and D. Marcus, “Hemp: A New Crop with New Uses for North America,” in Trends in
New Crops and New Uses, ed. J. Janick and A. Whipkey (Alexandria, VA: American Society for Horticultural Science
Press, 2002).
F. Grotenhermen and M. Karus, “Industrial Hemp Is Not Marijuana: Comments on the Drug Potential of Fiber
Cannabis,” nova-Institute, http://www.internationalhempassociation.org/jiha/jiha5210.html.
See, for example, M. Shipman, “Is Hemp the Same Thing as Marijuana?,” North Carolina State University, February
15, 2019, https://phys.org/news/2019-02-hemp-marijuana.html; and D. Donnon, A. T. Kearney, “The New Green
Rush,” presented at a Food Institute webinar, January 31, 2019.
E. Small and D. Marcus, “Tetrahydrocannabinol Levels in Hemp (Cannabis sativa) Germplasm Resources,”
Economic Botany, vol. 57, no. 4 (October 2003); and G. Leson, “Evaluating Interference of THC Levels in Hemp Food
Products with Employee Drug Testing” (prepared for the province of Manitoba, Canada), July 2000.
Generally, all cannabis varieties are commonly considered to be of a single species. However, not all researchers