Farnesene, a terpene common in green apples and turmeric, is one of the compounds that helps cannabis benefit the body. Kevin Jodrey of Wonderland Nursery explains that farnesene is the “death smell of aphids,” which they emit on death, and plants use this terpene to drive away predation. He mentions a “woody” odor and describes it as “funky death.” Farnesene may be associated with skunky varieties from the 1980s and 1990s.
What is Farnesene?
Farnesene is a sesquiterpene, which means that it’s made up of three isoprene units (C15H24). There are two isomers of farnesene, alpha (α) and beta (β). α-Farnesene is present in green apple skins.  The apple begins to spoil and turn brown due to oxidation of α-farnesene. β-Farnesene, meanwhile, has the aforementioned insect-repelling properties due to being an alarm pheromone for aphids. 
What Plants Contain Farnesene?
Sources of farnesene in nature include ylang-ylang and chamomile.  Farnesene is the main terpene component of gardenia flower.  The terpene is common to several varieties of cannabis as well.  The Verdes Foundation dispensary in New Mexico cite cultivars including White Rhino and Tangerine Kush.
Farnesene Health Benefits
Sesquiterpenes have anti-inflammatory and bactericidal properties.  Farnesene is associated with a host of different benefits. For instance, in 2013, researchers looking at Eucalyptus globulus plants determined that the plants “may be useful in the treatment of oral disease” because its leaves are rich with α-farnesene.  α-Farnesene has anticariogenic properties, which is another way of saying that it helps combat tooth decay.
A 2015 study focusing on the composition of a β-farnesene-dominant chemotype of chamomile found that “it has been found to show antimicrobial, anti-inflammatory, antioxidant, antispasmodic, antiviral and sedative activities. It is also used as a treatment against sore stomach, irritable bowel syndrome and also as sleep aid.”
Farnesene also has industrial uses as it is sometimes added to plastic and rubber.
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