Farnesene

What is farnesene?

Farnesene is a sesquiterpene, a larger terpene built from 15 carbon atoms. It is actually a small family of closely related compounds. The two main types are alpha-farnesene and beta-farnesene, which differ only in where one double bond sits in the molecule.

It also has a job in nature. Aphids release beta-farnesene as an alarm signal, and some plants, including certain potato species, make it to keep insects away.

What does farnesene smell like?

Alpha-farnesene is the main source of the fresh, green smell on apple skins. Beyond that, farnesene is described with a wide range of notes: woody, green, herbal and lightly floral. Beta-farnesene leans more toward citrus and fruit, with some sources calling it tropical.

In cannabis, farnesene tends to be a background note. It can add a fresh, green edge rather than defining the whole smell.

Where is farnesene found besides cannabis?

Farnesene is far more common in other plants than in cannabis. Two of the best-known sources:

• Apples: alpha-farnesene sits in the natural coating on the skin and gives green apples their smell.
• Hops: some hop varieties carry large amounts of farnesene, and brewers and researchers link it with a pleasant, classic hop aroma in beer.

Does farnesene change how a strain feels?

Nobody can say for sure. Research on whether terpenes change how cannabis feels is early and mixed, and the "entourage effect", the idea that terpenes and cannabinoids work together, is still being tested.

Many websites make claims about farnesene, but people's reports are not proof, and it usually appears in cannabis at low levels. Enjoy it as part of a strain's smell, and use the THC and CBD numbers on the label to judge strength.

Farnesene vs Myrcene

These two often get compared because both show up in hops, but they are quite different. Myrcene is a smaller monoterpene and one of the most common terpenes in cannabis, often leading the lab report with an earthy, musky, ripe-fruit smell. Farnesene is a larger sesquiterpene that only turns up in some strains, usually in small amounts, with a greener, apple-skin smell. When farnesene does appear in cannabis, it is often alongside myrcene, so a strain can carry both.

Finding farnesene on a label

Some producers list the top terpenes on the package or in a certificate of analysis. Look for farnesene, alpha-farnesene or beta-farnesene. Because it is rare and usually minor, it often only appears in a full terpene breakdown.

Strains like White Rhino and Cherry Punch have been named as containing it, but terpene levels vary from batch to batch. The results for your own product are the best guide.