Terpene Chart: Smells, Temperatures, Familiar Plants

From lab sheet to nose

1. A batch analysis hands you a list of names. Your nose hands you black pepper, pine, warm citrus. A terpene chart is where those two versions of the same plant meet, one line per aroma compound, so a name from the laboratory sits next to a smell you already know and a temperature you can look up.
2. First column: the terpene name. That is a chemical identity and nothing else. It records which molecule was found, not the plant it came from, and not how much of it was there.
3. Second column: the smell most commonly reported for that compound. Pepper, pine, lemon peel. Recognition shorthand, and the reason most people open a chart like this at all.
4. Third column: an approximate boiling point. The figure describes the pure isolated compound on its own, rather than inside a plant, and it arrives rounded from published literature.
5. Fourth column: familiar sources. Plants where the terpene occurs in quantity, picked because you have almost certainly smelled it somewhere in a kitchen or a garden.
6. The scope is eight terpenes, all of them commonly reported in hemp and cannabis. A short list on purpose, and nowhere near the plant's full aromatic fraction, which runs to dozens of volatile compounds.
7. There is no fifth column. What these molecules do once inside a body is a separate question, and a far less settled one, so it stays off the grid entirely.
8. Read down a column and you get vocabulary. Read across a row and you get one molecule described four ways: what it is called, what it smells like, roughly what temperature turns it to vapour, and where else it lives.

Temperatures with a margin

The temperature column is the one people quote and the one that deserves the widest tolerance. Every number in it is an approximate value, rounded for the table. Put two charts side by side and they rarely agree to the degree, because published figures for the same molecule vary between sources. That is not sloppiness. It is what happens when a physical property gets measured under different conditions, on samples of different purity, then rounded. Pressure matters as well, which is why one row in this set sits slightly apart from the rest. So read the whole column as ranges rather than thresholds.

• Humulene appears at around 106 to 107 °C. That is an approximate value only, and not an ambient-pressure boiling point directly comparable with the other seven entries.
• Each temperature belongs to the pure isolated compound. Inside a plant extract, the same terpene sits in a blend of dozens of volatile compounds, and a blend has no single clean number.
• A gap of a few degrees between two published charts tells you something about measurement and rounding. It tells you nothing about the plant either chart was built from.
• The eight rows share a format, not a ranking. Same four columns for every molecule, and no hierarchy hidden in the order they appear.
• Nothing in this column describes what a temperature does to a person. It is chemistry on paper, and it stays there.
• Names and smells are the durable part of the chart. The numbers are context, and they come with a margin attached.

Overlap in the sources column

Scan the fourth column and the plant families refuse to stay in their lane. Black pepper next to hemp. Hops next to a conifer. That looks like an error, and it is not. A terpene is a molecule, and molecules pay no attention to botany. Beta-caryophyllene from a hemp flower is the same beta-caryophyllene as the one in a peppercorn: identical structure, identical boiling point, identical name on an analysis. Which is also why nothing here is arranged by species. There is no row for a variety, because a variety is not a molecule. It is a plant producing a mixture of them, in proportions that shift from field to field and harvest to harvest.

The mixture is the part worth keeping in mind. In an extract, no terpene ever turns up alone. It turns up inside a blend of dozens of volatile compounds, a few of them named on a report and many present in traces nobody bothers listing. Full-spectrum hemp extracts retain part of that aromatic fraction alongside the cannabinoids, and that single fact is the reason terpene names come up in a conversation about CBD oil in the first place. Strip the aromatic fraction out and words like myrcene and humulene would have stayed in the botany literature where they began.

Working with cannabinoids since 2014, we have watched those words travel from laboratory jargon into ordinary product questions. Someone smells something in a bottle and wants to know what it was. A chart answers that far and stops: here is the compound, here is the smell it is known for, here is where else you have met it.

Heat, handling and what leaves first

1. Terpenes are volatile. That one property explains why an aroma table bothers with temperatures at all: these molecules leave the material they came from, and the boiling point is shorthand for how readily each of them goes.
2. Lower boiling points mean readier loss. Drying, heating and extraction each give a light molecule an exit, and a portion of it takes that exit.
3. Heavier molecules stay longer. Nerolidol and beta-caryophyllene sit at the far end of the column and persist through the same handling steps.
4. So the aromatic fraction of a finished extract is not the aromatic fraction of the fresh plant. Same list of names, different proportions.
5. Read the column as an order of departure rather than a set of switches. Light molecules first, heavy molecules last, and every figure approximate.
6. The number stays a physical property, not a kitchen instruction. It describes a pure compound measured on its own, not a bottle standing on a shelf.
7. Myrcene is the row most often at the top. The 2011 review by Russo described it as the most prevalent terpenoid in the plant [1], and it is the terpene most frequently reported as dominant across many cannabis and hemp varieties.
8. Variation between individual plants is considerable. A terpene leading one crop can sit well down the list in the next, which is why a chart describes molecules and promises no profile.

The open question standing next to the grid

Four columns, and not one of them covers what people actually ask about. Whether terpenes do anything alongside cannabinoids is contested, and has been for years. The 2011 review by Russo put the proposal on the table properly: that cannabis terpenoids and cannabinoids might interact, and that the possibility was worth investigating [1]. The same review named myrcene the most prevalent terpenoid in the plant [1]. Worth investigating means exactly that. A hypothesis under discussion, not a settled finding, and the honest answer today is that we do not know yet. A chart like this one is useful precisely because it stops short. A smell can be described. A temperature can be measured. What comes after that needs trials, and the trials remain thin.

So this stays a reference sheet: names, smells, temperatures, familiar plants. If you want the argument itself, it sits elsewhere, and both sides of it repay a slow read.

• Our page on the entourage effect sets out the case for and against the interaction proposal, which is where that debate belongs rather than in a table of temperatures.
• The overview of what terpenes are goes back a step into the chemistry: how these molecules form on the plant, and how a laboratory measures them once they are there.
• Other published charts will give temperatures a few degrees away from these. Comparing several sources is a reasonable habit, not a sign that one of them is wrong.