In times of intense stress, people sometimes let out their angst with a squeal — and a new study suggests that plants might do the same.
Unlike human screams, however, plant sounds are too high-frequency for us to hear them, according to the research, which was posted Dec. 2 on the bioRxiv database. But when researchers from Tel Aviv University in Israel placed microphones near stressed tomato and tobacco plants, the instruments picked up the crops’ ultrasonic squeals from about 4 inches (10 centimeters) away. The noises fell within a range of 20 to 100 kilohertz, a volume that could feasibly “be detected by some organisms from up to several meters away,” the authors noted. (The paper has not been peer reviewed yet.)
Animals and plants might listen and react to the silent screams of plants, and perhaps humans could too, with the right tools in hand, the authors added. The idea that “sounds that drought-stressed plants make could be used in precision agriculture seems feasible if it is not too costly to set up the recording in a field situation,” Anne Visscher, a fellow in the Department of Comparative Plant and Fungal Biology at the Royal Botanic Gardens in the U.K., told New Scientist.