Hemp is Cannabis sativa L. grown for fibre, grain, oil or low-THC flower and extracts. Botanically it is the same species as drug-type cannabis. The legal difference is chemistry: many jurisdictions define hemp as cannabis with no more than 0.3% THC on a dry-weight basis, though they differ on which THC counts (delta-9 THC only, or total THC including THCA) and which plant parts are sampled.
In practice
The US federal definition since 2018 used 0.3% delta-9 THC on a dry-weight basis, with pre-harvest testing rules later moving toward total THC; Congress has since changed the federal definition again with effect around late 2026being reviewed. Canada and the EU also use a 0.3% THC threshold for hemp cultivation under their own rules. A crop that tests "hot" above the limit may have to be destroyed.
Many fibre and grain hemp cultivars are monoecious, bred on purpose to carry male and female flowers on one plant. That is a deliberate agricultural trait, not the norm for drug-type cannabis.
Rules differ by country, state, province and city, and change often. This is a general definition, not legal advice: check local rules.
Don't confuse with
- Drug-type cannabis: same species, high-THC chemotype.
- CBD flower: often legally hemp, but grown and sold as smokable flower.
The single botanical species, in the family Cannabaceae, that covers all hemp and drug-type cannabis; "L." credits Linnaeus, who named it in 1753.THC (Δ9-tetrahydrocannabinol) is the neutral, decarboxylated cannabinoid mainly responsible for cannabis's reported intoxicating effects; the living plant makes it almost entirely as THCA.Dry-weight basis reports a result per gram of sample with its water removed, while as-received basis reports it per gram as delivered, water included; dry-weight figures are always higher.THCA (tetrahydrocannabinolic acid) is the acid cannabinoid that drug-type cannabis makes in its trichomes; heat or time decarboxylates it into THC, losing about 12% of its mass.Having both male and female flowers on the same individual plant; in cannabis, a trait deliberately bred into some hemp cultivars, not the natural norm.A female flower with a pistil but no functional stamens; in cannabis, a bract-wrapped ovary topped by two stigmas.A chemotype is a plant's chemical phenotype, in cannabis usually its dominant cannabinoid class: THC-dominant (I), mixed (II), CBD-dominant (III), CBG-dominant (IV) or cannabinoid-free (V).CBD (cannabidiol) is a non-intoxicating neutral cannabinoid formed when CBDA decarboxylates; hemp-type and CBD-dominant cannabis make it mainly as CBDA in their trichomes.Marijuana is a common name for drug-type cannabis flower; the word entered US English from Mexican Spanish and became the standard term in 20th-century law.Total THC is a calculated figure, Δ9-THC plus 0.877 × THCA, estimating the maximum THC a sample could yield after full decarboxylation.Compliance testing is mandatory lab analysis of cannabis or hemp for potency (often total THC) and contaminants, required before sale or to prove legal status.
