Experts at the National Center for Atmospheric Research (NCAR) in Boulder, Colorado said the findings may fuel new research into the behavior of plants and their impacts on air quality, and could help give farmers an early warning signal about crops about to fail.

"Unlike humans, who are advised to take aspirin as a fever suppressant, plants have the ability to produce their own mix of aspirin-like chemicals, triggering the formation of proteins that boost their biochemical defenses and reduce injury," said NCAR scientist Thomas Karl, who led the study.

"Our measurements show that significant amounts of the chemical can be detected in the atmosphere as plants respond to drought, unseasonable temperatures, or other stresses."

Scientists long had known plants in a laboratory setting could produce methyl salicylate, which is a chemical form of acetylsalicylic acid, or aspirin.

Researchers however never had detected methyl salicylate in an ecosystem or verified plants emitting the chemical in meaningful quantities into the atmosphere.

"Biosphere-atmosphere interactions are important to the understanding of the Earth system," said Cliff Jacobs, program director in NSF's Division of Atmospheric Sciences. "This fortuitous discovery of methyl salicyclate in quantities not anticipated adds to an already important study."

Also intriguingly, "these findings show tangible proof that plant-to-plant communication occurs on the ecosystem level," said NCAR scientist and study co-author Alex Guenther. "It appears that plants have the ability to communicate through the atmosphere."

The findings were published in the latest edition of Biogeoscience and was funded by the National Science Foundation.

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