An Agronomist on GemmaCert’s potency test device


GemmaCert Cannabis Potency Testing: A Review by Dr. Curt Livesay

The following entry was submitted by Dr. Curt Livesay on his personal experience using GemmaCert. Dr. Livesay is a professional agronomist, a certified crop advisor and a licensed commercial pesticide consultant through the Washington State Department of Agriculture.

I came to the cannabis industry as a complete outsider from commercial agriculture. More specifically, I’m an agronomist who specializes in plant and soil fertility in commercially grown crops like corn, soybeans, and wheat. I have been fairly successful with my career and that caught the attention of some individuals who asked me to come work with them in cannabis.

Since I had no prior experience with cannabis (neither production nor consumption), I also had no pre-conceived notions about the way things “should” be done.  Sometimes that’s bad because I’ve had to learn a lot of things by killing plants—sometimes on purpose, and too frequently not on purpose.  Sometimes, though, a fresh perspective from an outsider can be a really good thing because it questions the status quo.  In short, just because something is good doesn’t mean that it can’t be great.  Just because something works doesn’t mean that it can’t work better.

One of the things that I question in the cannabis industry is the way that cannabinoid potency testing is done.  I’m very concerned with some of the underlying assumptions inherent to these tests.  For example, where I live, in Washington State, the testing requirement outlined in Section 3 of the WAC 314-55-101 is that a producer must submit 4 random samples that are 1 gram each for every 5 lb “lot” produced.  Each sample is supposed to be pulled from a different quadrant of said 5-lb lot.  The logic behind this state mandated sampling procedure is sound from a statistical perspective.  That is, they have essentially mandated a stratified random sample that theoretically should truly represent the “population,” which in this case, is 5 lbs of cannabis flower.  The major problem with this logic, however, is the underlying assumption of a certain level of homogeneity among the target population – in other words, that the buds are similar enough for a random sample to be truly representative.  Past research indicates that this is simply not true.  For example, a study conducted in New Zealand and published in 2010 found a wide latitude of within-plant variation across 6 different plants (Knight, et al., 2010).

Cannabis testing labs in the United States also readily acknowledge this issue.  For example, the following statement was taken from the Florida based ACS Testing Laboratory’s website:

Through no fault of growers, manufacturers, or retailers, potency results can vary based on which part of the plant is tested. For example, a supplier may send a sample from a particular plant’s flower that was exposed to sunlight and naturally contains a high percentage of cannabinoids. But if that same supplier had sent a bud from the under canopy instead, the results would be much different. Under canopy buds are exposed to less light, which means they’ll inevitably contain less THC. Even when samples are carefully chopped up and homogenized, variations in potency tests are common.

Given the degree of within-plant variation, a test result obtained using a destructive sampling method such as that from an HPLC gives the user absolutely zero data that is applicable to anything other than the single bud that was sampled.  And while measurement standards are great and all, destructive sampling also precludes any sort of reliability analysis through replication of a given test on a given bud.

As an agronomist, my job is to help my clients increase their profitability.  I believe that the best ways to do this are by improving upon their efficiency and consistency.  As such, the aforementioned limitations inherent in potency testing sent me on a quest for a non-destructive sampling method that my clients could employ to pre-test their samples so that they would know that they were able to actually accomplish the ultimate goal of the previously state-mandated testing requirements – that is, that the sample would actually represent the lot.

That’s how I found GemmaCert.  The GemmaCert’s non-destructive sampling method allows the producer to test multiple buds from a given lot.  Armed with this data, they can then send off the buds that best represent the lot. GemmaCert has developed a truly revolutionary technology that I believe is absolutely critical for every cannabis producer who cares about the quality of their product.

Fast forward a couple of years and I now find myself in fairly high demand as a hemp consultant given my experience in both cannabis production and commercial scale agriculture. Given the strict regulatory issues surrounding hemp production, in my humble opinion, the use of the GemmaCert may be even more imperative here than in drug-type cannabis production.  Hemp producers risk losing their entire crop (read: ALL of the money invested AND all of the potential profit) if their product tests too high in THC.  For this reason alone, the GemmaCert makes sense to me simply as a risk mitigation strategy.

There are a lot of facets of the bourgeoning cannabis and hemp industries that still feel like the proverbial Wild West; however, I do not believe that potency tested should be among them.

I simply cannot imagine producing cannabis, whether adult-use or medicinal or industrial hemp, without the use of the GemmaCert.


Knight, G., Hansen, S., Connor, M., Poulsen, H., McGovern, C., & Stacey, J. (2010). The results of an experimental indoor hydroponic Cannabis growing study, using the ‘Screen of Green’   (ScrOG) method—Yield, tetrahydrocannabinol (THC) and DNA analysis. Forensic Science International, 202, 36-44.

Schmidt, E. (2019, October 14). How accurate are THC potency tests? Retrieved from the ACS
Laboratory website:[/vc_column_text][/vc_column][/vc_row]2020-09-10 06:55:18Itayganot

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