How to Identify ‘Good’ Cannabis Biomass
First, what is “biomass”?
When discussing quality cannabis or hemp in general, most of the talk focuses on the ‘colas’, or ‘buds’ of the plant—the central flower cluster that forms along the upper portion of the main stems and large branches in a mature, female cannabis plant. This is the part of the plant with the highest density of trichomes and therefore the highest quantity of desirable compounds such as cannabinoids (THC, CBD, etc.) and terpenes.
The bud is the most prized part of the cannabis plant. It’s what is most often smoked in its dried and cured form or extracted for high-end cannabis extracts. To get to this state, once mature, the plants are dried, and the buds are removed from the bulk stems and stalks. They are then trimmed (usually by hand) of all the excess leaves prior to a final curing.
All of the excess plant material from this process, is collectively referred to as “biomass”.
Often, some farmers will grow large fields of low-grade hemp or cannabis, and harvest this with more conventional farming methods, homogenizing (blending together) the entire plant (except for the stalks and stems), and this is then also referred to, and sold as “biomass”. So, when you’re evaluating your biomass, you may notice that it contains a mixture of many different plant components.
Biomass, in both cases, still has desirable compounds such as cannabinoids and terpenes that can be extracted because for most processors, their only goal is to extract CBD and/or THC.
The difference between the two types of biomass comes down to the concentrations of cannabinoids. Buds on high-quality cannabis can have a potency that usually ranges between 15-25%. While high quality biomass generally can range between 5-15% potency of cannabinoids and terpenes by weight.
As the market gets more competitive, processors have looked to more cost-effective ways of producing bulk THC and CBD products—rather than the highly-priced ‘buds’. This has most predominantly taken the form of purchasing and extracting the biomass that results from largescale agriculture or is the byproduct of the smoke-able cannabis ‘flower’ industry. Therefore, for most cannabis (and hemp) processors, when we discuss ‘good’ cannabis, we are really talking about ‘good’ biomass
So How do you Identify What is ‘Good’ Biomass?
The first thing to do is to make sure your biomass is homogenized, or that the sample you are examining is a good representation of the whole batch you have chosen to process. Be warned that when processing at large scale, even single lots and batches that are inputted can vary greatly in quality.
When identifying quality buds and colas, things like; bud structure, how well the buds were trimmed, and trichome density are immediately apparent. When examining biomass, however, not only do you have to inspect a bit closer but take a look at things like how—or if—the buds were trimmed, and their overall structure. These factors are less apparent but still important.
1. Trichome Density
Trichomes are the part of the plant, found most densely in the colas, that produce the terpene and cannabinoid compounds we recognize and desire. Therefore, trichome density is an approximate yet direct way of inferring how potent your biomass is. The more trichomes (the higher density) generally = more potent biomass.
2. Biomass Constituents
As mentioned above, especially when processing large hemp batches that have been grown and processed by large farms, while the biomass is hopefully consistent overall, if examined closely you should be able to identify the plants’ constituent parts.
In very simplified terms there are 3 types of plant constituents you’ll often be able to identify in your biomass:
- Buds are exactly that, the colas, buds, or pieces of the colas that were trimmed off. These are the highest quality constituents and have the highest density of trichomes.
- Leaves are primarily what biomass consists of (along with small pieces of trimmed off buds) when it is sourced from cannabis flower manufacturers. Leaves are the most archetypal part of the cannabis and hemp plants and have a very recognizable look and structure, they also have some trichomes, and small amounts of cannabinoids, but not nearly as much as the buds.
- Stems and stalks. These look like small pieces of chipped up stems or wood. They contain zero to minute amount of cannabinoids and are the lowest grade constituent.
- The more buds = more trichomes = higher potency
- Leaves = medium grade material
- Stems = low potency material
3. Odor (Smell)
Any connoisseur of cannabis will tell you that, perhaps the best indicator of quality cannabis is a strong, recognizable, floral, and ‘dank’ smell or odor.
The highest quality and most prized forms of cannabis are actually most prized for their terpene content. There are many strains of cannabis that produce high amounts of cannabinoids like THC and CBD, but terpene content is what causes the smell and taste of the bud. And current research is beginning to study how terpenes also contribute to the psychological effects, or high, that is recognizable from smoking high-grade cannabis flower. This, the terpene profile, is what users and connoisseurs alike fall in love with and will make them go back to and grow that specific plant again and again.
However, these terpene compounds are very fragile. The reason you smell them so prominently is because their vapors are ‘boiling’ off the plant at room temperature and atmospheric pressure. Due to this effect, old cannabis, or improperly dried and cured cannabis, will be devoid of a lot of terpenes and loose its complexity of smell and taste.
Terpene compounds are also produced by the trichomes of the plant, so ‘good’ and ‘fresh’ smelling sample of cannabis (or hemp) biomass tells you two things:
- Its relatively fresh and has probably been stored, cured, and dried properly.
- It is probably more potent because the stronger the smell, the more trichomes are present on the plant
The plant should smell dank, citrusy, floral, and/or chocolatey. If your biomass smells of grass, hay, pickles, and repugnant smells, these are signs of old and low quality cannabis.
Like any high-quality leafy vegetable, the color of your biomass should be a deep and vibrant green. Although, some cannabis plants have lighter and darker greens, oranges, and purples evident as well, what you don’t want to see are colors in the spectrum of yellows and browns—indicating old, mishandled, and/or improperly dried or cured cannabis.
The orange color you will often see in good cannabis are the stigmas, not the buds or leaves. Orange color on the leaves is the same as browning and usually indicates old or very improperly dried material.
The popular major cannabinoids THC and CBD, while not as sensitive as terpenes, are still sensitive compounds. When biomass is brown or yellow and has been dried or stored improperly, this means that the THC and CBD have begun to degrade into other, less desirable, compounds such as CBN. Therefore, reducing the potency of the biomass.
5. Mold and Pests
While the previous 4 points primarily allowed you to quickly asses the potency of the biomass (% of cannabinoids like THC or CBD by weight), this final point is just as important, and allows you to assess the biomass for common contaminants.
Luckily, while being perhaps the most dangerous category of things to assess your cannabis for, it’s quite easy to notice the most common ones. Needless to say, if you notice these, your biomass is probably sliding quickly from the ‘good’ range to the ‘terrible’ end of the spectrum.
- Mealy bugs or Aphids: Little white / gray looking fuzzy specs.
- Spider mites and thrips: Spider mites are too small to see, but you may see their webs. Thrips are small yellow worm-like bugs, and both pests will result in yellow/white specks all over the leaves. Also, look out for bug droppings (from all of the above) that look like small black specs.
- Bud rot / mold: Most often is found on the stem of the cola, closest to the base, and in very dense buds. Looks like a typical white fuzzy mold.
- Powdery Mildew: Leaves a white powdery, flour, like substance that can be found on the leaves and in the buds.
6. Test often and always!
A final note on how important it also is to have your biomass analytically tested. It cannot be understated how valuable and important it is to have a representative sample of any biomass you’re considering using for extraction sent to a 3rd-party lab to be evaluated for:
- Cannabinoid and terpene content
- Heavy metals
While the above tips we’ve offered will do a great job in identifying 95+% of bad biomass they are no substitute for analytical testing by an unbiased 3rd party lab.