After viewing the damage that forest fires can wreak, it might seem counterintuitive that some plants fare better after being exposed to smoke. This phenomenon has been observed in a number of species, but it was unclear just what bestowed these benefits. Scientists report today in the journal Science that they have identified the active ingredient in smoke that improves plant germination.

Gavin R. Flematti of the University of Western Australia and his colleagues first analyzed smoke from burnt filter paper, which is significantly less complex than smoke from burning plants. From the paper smoke, the researchers isolated a compound that promotes increased sprouting in three types of plants at a variety of concentrations, even those as low as one part per billion. Using spectrometry, the team identified the substance as a type of chemical known as a butenolide and confirmed its presence in smoke from burning plants. Further testing with 10 additional plant species corroborated its positive effects.

The researchers note that the find could be a boon for horticulture, agriculture and land restoration. The mechanism by which butenolide promotes germination remains unknown, however.