A novel drone system is currently being tested in Denmark. Don’t worry, it will be targeting weeds not people. The goal is to reduce herbicide use by limiting application to heavily infested areas. These drones are equipped with a special camera that detects wavelengths corresponding to the reflective signatures of specific weeds and crops. For example, thistle can be easily detected because it absorbs more yellow light than the surrounding beet plants. When the drone detects areas that may contain a dense population of weeds, it automatically sends a ground vehicle to that location to deploy a minimal spray of a herbicide. A great leap for “green” chemistry.