Researchers discovered that a beneficial fungus called Beauveria bassiana produces odorous chemicals that can discourage pest insects from eating crops. When certain strains of this fungus release their characteristic smell (particularly a compound called 3-methylbutanol), larvae of the fall armyworm pest eat less and avoid treated plants. Interestingly, the plants themselves respond by producing defensive compounds when exposed to these fungal odors. This finding suggests a new approach to pest control that harnesses the natural chemical communication between fungi, plants, and insects.