terpene

An aromatic organic compound produced by plants — the molecular basis of the scents released by pine needles, sage leaves, citrus peel, lavender, and cannabis. Terpenes are the chemistry behind the smell of a forest after rain, the sharp bite of juniper, the resinous sweetness of a sun-warmed pine. Plants produce them as defense against herbivores and as attractants for pollinators, but the compounds also play ecological roles barely understood: they influence cloud formation, communicate between trees, and may suppress competing vegetation. The forest smells the way it does because it is speaking.