Human Achievement Of The Day: Replacing Herbicides With Lasers

This story demonstrates very clearly how technology can be used to create a future with a cleaner environment and underscores why we must protect access to resources so people have the time and money to come up with more efficient and environmentally friendly technology.

As the folks over at Treehuger.com noted, there’s a range of concerns regarding the use if herbicides in farming and gardening, “ranging from protecting the workers using the chemicals to groundwater contamination.” On the other hand, in organic farming, the methods of controlling weeds include pesticides, hand-weeding, or flame throwers that are either as harmful as conventional weeding or impractical for large-scale agriculture. However, farmers may soon have another more environmentally friendly option: weed-targeting lasers. A team of scientists at the Leibniz University of Hannover Germany, and Laser Zentrum Hannover (LZH) are in the process of testing weed-targeting robot drones that utilize CO₂ lasers to kill plants that compete with desired plants for resources.

There are some challenges in getting the robots to differentiate between wanted plant species and weeds, as well as having the lasers hit precisely at the plant’s center. To do this, the scientists use cameras to film the plants and software to measure the plants so the lasers can be shot at precisely the right spot. Another challenge is getting the strength of the radiation just right. If it’s too low the radiation can “encourage growth.”

While the current research is testing lasers that run on rails in a greenhouse, Thomas Rath, a lead on the project, believes that drones may be used to “swarm over the field” for larger-scale agricultural use.