What is THCa & Is This Legal? THCa vs THC Explained

Legal Opinion Letter

What is THCa & Is This Legal? THCa vs THC Explained

If you already have some experience with cannabis, you are probably already familiar with Delta-9 THC, one of the most popular cannabinoids found in cannabis. However, “what is THCa?” is a question that has been coming up more and more frequently since the enactment of the 2018 Farm Bill as well as questions regarding the differences between “THCa vs THC”.

What is THCa? “THCa” is the abbreviation for “tetrahydrocannabinolic acid”, a cannabinoid produced in abundance naturally by the cannabis plant. THCa on its own is non-psychoactive and does not produce intoxication; however, under certain conditions, including exposure to heat, light, and time, it can convert to delta-9 THC, which does have an intoxicating effect. The conversion from THCa to delta-9 THC is known as “decarboxylation” and occurs primarily when THCa is heated.

What is THCa flower?  “THCa flower” or “THCa hemp flower” is the name for cannabis buds with delta-9 THC levels that do not exceed 0.3% by dry weight, but which have high levels of THCa. StrainX’s THCa flower is 100% natural with all cannabinoids produced organically by the plant itself. StrainX THCa flower is NEVER dipped, sprayed, or otherwise infused and is ALWAYS completely natural.

THCa vs THC: What’s the Difference? THCa and delta-9 THC are both different cannabinoids found naturally in the cannabis plant. THCa is the acidic inactive form of delta-9 THC, and the primary cannibinoid, found in the highest concentrations, occurring naturally in high THCa cannabis flower. THCa converts into delta-9 THC through a process called “decarboxylation” such as when cannabis is exposed to heat. THCa on its own does not have an intoxicating effect. However, once decarboxylated, it can convert to delta-9 THC, which does have an intoxicating effect. Cannabis plants naturally express large percentages of THCa, but not a whole lot of THC.

Marijuana vs Hemp: And the Difference Is? The terms “marijuana” and “hemp” are specific legal terms of art under federal law which both describe the same plant referred to in botanical terms as “cannabis.” The difference, however, is that dry cannabis which does not exceed 0.3% delta-9 THC is considered “hemp” and is legal under federal law, whereas cannabis which does exceed 0.3% delta-9 THC by dry weight is considered marijuana and is not legal federally. The federal definitions only consider delta-9 THC and do not reference THCa or any other cannabinoid.

Then is THCa a Legal Loophole? A loophole is by definition something that is lawful. The word is usually used in the context where something is understood to be lawful, but where people think it shouldn’t be. The reason for the controversy is the reality that a large percentage of the cannabis sold under state licensed recreational adult-use and medicinal “marijuana” programs such as in California, Colorado and Oregon, would actually qualify as 2018 Farm Bill legal THCa “hemp” flower since those flowers are high in THCa but have less than 0.3% delta-9 THC. This is because the cannabis plant naturally expresses large concentrations of THCa, but not a whole lot of delta-9 THC.

Will heating THCa hemp flower make users feel “high”? Although everyone is different, it is possible that a user will feel intoxicated or “high” after consuming decarboxylated (i.e., heated) THCa flower. Users should be aware of the possibility of feeling “high” or intoxicated when using this product. THCa flower should not be sold to minors or anyone under the age of 21.

Will using THCa hemp flower cause users to fail a drug test? Yes. THCa hemp flower contains cannabinoids, including THC, which may cause a user to fail a drug test. Therefore, individuals should not use THCa hemp flower if they are subject to drug testing.

Is THCa hemp flower lawful under the 2918 Farm Bill? Yes, this is because the federal 2018 Farm Bill distinguishes between lawful harvested hemp and unlawful marijuana based on the levels of delta-9 THC, not THCa.[1] Finished cannabis consumer products, including post-harvest cannabis flowers and buds, with no more than 0.3% delta-9 THC by dry weight are lawfully hemp, regardless of the amount of THCa or any other cannabinoid that it contains. Additionally, the federal Controlled Substances Act, which regulates drugs, removes hemp from the definition of marijuana. In other words, hemp is not an illegal controlled substance under federal law.[2]

What does the DEA say about THCa hemp flower? THCa hemp flower meets the DEA’s definition of lawful hemp. According to the DEA, “material that is derived or extracted from the cannabis plant such as tissue culture and any other genetic material that has a delta-9 tetrahydrocannabinol concentration of no more than 0.3 percent on a dry weight basis meets the legal definition of “hemp” and is thus not controlled under the CSA.”[3]

Have any federal courts ruled on THCa hemp flower? Not specifically. However, the federal Ninth Circuit Court of Appeals has stated the following regarding another type of hemp product, which supports the legal status of THCa flower: “the only statutory metric for distinguishing controlled marijuana from legal hemp is the delta-9 THC concentration level.”[4] Additionally, the federal district court for the Eastern District of Arkansas ruled: “Under the 2018 Farm Bill’s standard, the only way to distinguish controlled marijuana from legal hemp is the delta-9 THC concentration level. Additionally, the definition extends beyond just the plant to “all derivatives, extracts, [and] cannabinoids.” The definition covers downstream products and substances, if their delta-9 THC concentration does not exceed the statutory threshold.”[5]

Is THCa hemp flower lawful in all states? No. State laws differ regarding whether or not harvested hemp and hemp flower can be sold or possessed and if a license or permit is required in order to handle it. Additionally, some states calculate the concentrations of both delta-9 THC and THCa, rather than just delta-9 THC, to determine if a harvested cannabis bud is lawful hemp or unlawful marijuana. This calculation, in which both THCa and delta-9 THC are used to determine the legal status of a harvested hemp flower, is referred to as “total THC”. It is the calculation used in all states for pre-harvested hemp. The total THC calculation is also used in some states, but not all states, for harvested hemp and/or hemp products. You should not possess or sell THCa hemp flower if it is illegal in your state. You should consult with a lawyer if you are unsure of the legal status of THCa hemp flower in your state.

Is THCa hemp flower lawful in Texas and North Carolina? Yes. THCa hemp flower is lawful in both Texas (TX) and North Carolina (NC). This is because both TX and NC only use the concentrations of delta-9 THC, not THCa or any other cannabinoid, in determining the legal status of harvested cannabis or a cannabis product, including THCa hemp flower.

Can THCa hemp flower be shipped across state lines? Yes, the interstate transfer of hemp, which includes THCa hemp flower, is authorized by federal law. 7 USC § 1621 subsection 10114(b), states in relevant part: “No State or Indian Tribe shall prohibit the transportation or shipment of hemp or hemp products produced in accordance with subtitle G of the Agricultural Marketing Act of 1946 (AMA) (as added by section 10113) through the State or the territory of the Indian Tribe, as applicable.”[6] Although state laws vary with respect to hemp and hemp products, it is absolutely clear that states and Indian tribes may not prohibit the transport of them through their borders.

Is it lawful to consume THCa hemp flower in public or to have a package of it open in a car? Because state laws vary regarding THCa hemp flower, and also due to the current confusion about its legal status, we do not recommend consuming it in public or having an open package of it in vehicles. Additionally, we recommend that it be sold to consumers only in pre-packaged, sealed bags or containers with labels clearly stating that it is lawful hemp.

How can you be sure that the THCa hemp flower you are purchasing meets the legal requirement for hemp? We recommend reviewing a lab report, called a Certificate of Analysis (COA), in conjunction with your attorney. A COA shows the levels of cannabinoids, including delta-9 THC, in a hemp product. We always provide a current COA for our hemp products showing that they are compliant under federal law and the laws of TX and NC at the time they leave our facility. Importantly, if your state uses a total THC calculation[7] to determine whether post-harvest cannabis flower is lawful, then THCa hemp flower is probably not legal in your state and we recommend that you consult a lawyer before receiving, possessing, or selling it.

How should you store THCa hemp flower? All of StrainX’s THCa hemp flower is tested before leaving its facilities to ensure legal compliance. In other words, StrainX only possesses and distributes lawful hemp. However, it is important to understand that THCa hemp flower will change form and become illegal marijuana if the THCa in it decarboxylates and raises the concentration of delta-9 THC to above 0.3%. In addition to the natural process of decarboxylation over time, THCa will also convert to delta-9 THC when it is exposed to heat and light. We strongly recommend storing THCa hemp flower in a cool, dark, dry location in order to limit the amount of THCa that is unintentionally converted to delta-9 THC through the process of decarboxylation.

Does StrainX have a legal opinion letter about THCa hemp flower? Yes. StrainX has a legal opinion letter regarding the legal status of THCa hemp flower. Please be advised that this informational document and the opinion letter were created solely for Strain Exploration and that they are not intended to be, nor should they be relied upon as, legal advice to any other person or company. Contact your lawyer if you have legal questions about THCa hemp flower.

Please note that this document and opinion letter were prepared exclusively for StrainX and are not intended to be legal advice or relied upon by any other person or entity.

Doesn’t USDA Have a Total THC Standard? USDA does indeed have a pre-harvest total THC test which takes into account a combination of both THCa and delta-9 THC by using a post-decarboxylation test where total THC must come in not exceeding 0.3%. Thus, in order for a hemp plant to be harvested, it must pass a total THC test in accordance with USDA regulations. However, after that point the USDA jurisdiction ends as it only governs production and cultivation up to the point of harvest. Thereafter, other federal agencies may intervene depending on for what use the cannabis is being directed. For example, if extracting the cannabis to produce CBD oil, the FDA has responsibility to regulate. In terms of whether particular cannabis is a controlled substance, the DEA regulates and has stated on multiple occasions reiterating the 2018 Farm Bill statute which is that hemp is cannabis with no more than 0.3% delta-9 THC, no other metric.

How can hemp pass a total THC test pre-harvest, then have high THCa post-harvest? For those unfamiliar THCa, there is a question as to how a plant that doesn’t have a lot of THCa pre-harvest, can suddenly have a lot of THCa later post-harvest. The way this happens is by growers using advanced strains and genetics which are bred to develop most of their THCa in the last 30 days prior to maturity and harvest. Thus, by testing early and then harvesting within the 30 day USDA time limit, growers are able to achieve total THC compliant USDA pre-harvest tests, and then afterwards maximize THCa production for the last 30 days until harvest while keeping delta-9 THC under 0.3%. The final result is USDA compliant high THCa hemp flower with less than 0.3% delta-9 THC, but with high levels of THCa.

[1] See 7 U.S.C. § 1639o(1) (2018 Farm Bill): “The term ‘hemp’ means 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.” Note that under federal law, the 

mandatory pre-harvest hemp testing does take into account the THCa concentration, but that is only

with respect to cultivating hemp plants and does not apply to finished products. Individual state laws may vary. 

[2] See 21 U.S.C. § 802(16)(B) (Controlled Substances Act): “The term “marihuana” does not include—

(i) hemp, as defined in section 1639o of title 7.”

[3] You can read the DEA’s letter here:

https://s3.documentcloud.org/documents/21580238/21-7692-shane-pennington-cannabis-seeds- tissue-genetic-material-11-18-21-signed-1.pdf

[4] AK Futures LLC v. Boyd St. Distro, LLC, 35 F.4th 682 (9th Cir. 2022)

[5] Bio Gen LLC et al v. Sanders et al, 4:23 CV 718 BRW (September 7, 2023) [Document 65]

[6] 7 USC § 1621 subsection 10114(b) can be read here:


[7] A total THC calculation adds the delta-9 THC amount to 87.7% of the THCa amount to see if the total THC does not exceed 0.3%. Fortunately, most COAs show the total THC amount in addition to delta-9 THC so that you do not need to do the calculation yourself.

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