Hemp vs Marijuana (Pot): What Is the Difference?

Hemp and marijuana, also called pot, come from one species. What separates them in the United States is a number written into federal law. This page describes that law as of October 9, 2026. This page is general information, not legal advice.

Are hemp and marijuana the same plant?

Yes, they are the same species, Cannabis sativa L. The Congressional Research Service (CRS) notes that growers describe them as different varieties or cultivars, while regulators classify them by chemical content.

Penn State Extension says the same thing from the farm side: “Industrial hemp and marijuana are different cultivars bred from the same species”. An older CRS report, Hemp as an Agricultural Commodity, calls them “genetically distinct forms of cannabis” told apart by their use, chemical makeup and cultivation practices.

The chemical in question is delta-9 tetrahydrocannabinol (THC). CRS describes it as the primary psychoactive compound in cannabis.

The legal line: 0.3% THC

The federal line is 0.3 percent delta-9 THC on a dry weight basis. It comes from the Agriculture Improvement Act of 2018, the 2018 farm bill (Public Law 115-334, section 10113, enacted December 20, 2018).

That law added a definition at 7 U.S.C. 1639o. Hemp is the plant Cannabis sativa L. and any part of it, including seeds, derivatives and extracts, “with a delta-9 tetrahydrocannabinol concentration of not more than 0.3 percent on a dry weight basis”.

The same law changed the drug statute. The Controlled Substances Act defines “marihuana” at 21 U.S.C. 802(16) as all parts of the plant Cannabis sativa L., and then says the term does not include “hemp, as defined in section 1639o of title 7”.

So the two definitions lock together. Cannabis at or under the line is hemp, an agricultural crop. Cannabis over the line is marijuana, a controlled substance.

The definition is changing in late 2026

Congress rewrote the hemp definition in section 781 of Public Law 119-37, signed November 12, 2025. The 0.3 percent figure stays, but it will apply to “total tetrahydrocannabinols concentration (including tetrahydrocannabinolic acid)”.

The change was set for November 12, 2026. Public Law 119-103 delays most of it until December 11, 2026. The full detail, with dates and quotes, is on the hemp ban explained.

Where marijuana stands federally

Marijuana is split between two schedules as of October 2026. A DEA final rule published and effective on April 28, 2026 (91 FR 22714) moved two categories to Schedule III:

• drug products containing marijuana that FDA has approved, and
• marijuana subject to a state-issued license for medical purposes.

The rule says other marijuana stays where it was. It keeps “in schedule I all unlicensed marijuana crops, bulk marijuana, and any marijuana or marijuana extract that has not yet been incorporated into a FDA-approved drug product”. It also states that “synthetic THC remains in schedule I”.

The rule leaves hemp alone. In its words, it “does not affect the status of hemp (as defined in 7 U.S.C. 1639o), because hemp is excluded from the definition of marijuana”.

Broader rescheduling is still pending. A DEA notice set a hearing on moving marijuana as a whole to Schedule III, starting June 29, 2026 and ending no later than July 15, 2026. The law firm Morgan Lewis reported on September 24, 2026 that the hearing had concluded and the parties were waiting for the judge’s recommended decision. This site found no final rule on it in the Federal Register as of October 9, 2026.

How hemp is tested, and what “hot” hemp means

Hemp is tested before harvest, and a crop over the limit cannot be sold as hemp. The rules are in USDA’s Domestic Hemp Production Program, 7 CFR part 990.

The lab result is read with its measurement of uncertainty. A sample meets the “acceptable hemp THC level” when that range “includes 0.3 percent or less” (7 CFR 990.1).

A crop that fails is informally called “hot” hemp, a term used in press coverage such as Stateline’s. The regulation defines remediation as “removing and destroying flower material, while retaining stalk, stems, leaf material, and seeds”. Disposal means making the crop “non-retrievable or non-ingestible”.

A grower who makes reasonable efforts and stays at or under 1.0 percent has not committed a negligent violation, under 7 CFR 990.6. The same section says a negligent violation does not lead to criminal enforcement.

How the crops are grown and used

Hemp is grown as a field crop for its stalk and seed, or as a spaced crop for its flower. Penn State Extension gives these figures for hemp:

The flower is where the chemistry sits. A 2023 review in the journal Molecules states that cannabinoids are made “within the glandular trichomes present mainly in flowers of female plants”.

That explains the split in uses. Fiber and grain hemp are harvested for parts of the plant that are not the cannabinoid source. See industrial hemp for the crop and its US production figures. Flower crops, whether hemp for CBD or marijuana, are grown for the cannabinoids themselves. The difference between seed oil and a flower extract is covered in hemp oil vs CBD oil.