Do you like the smell of fresh cut grass? The smell of cut grass is not pleasant. It’s the smell of chemical defences and first aid. The fresh, “green” scent of a just mowed lawn is the lawn trying to save itself from the injury you just inflicted.
The smell is a mixture of oxygenated hydrocarbons that include methanol, ethanol, acetaldehyde and acetone, called green leaf volatiles (GLV). Besides releasing a unique “green” odour, GLVs help form new cells to heal wounds faster, prevent bacterial infection and fungal growth (like an antibiotic), and produce compounds to prevent further damage.
The plants deliberately emit volatile compounds in response to damage.