Lasers match common herbicides at zapping weeds

Good news! However, the machine (see photo below) looks unwieldy! Some miniaturization might be necessary.

"Commercial laser weeders are large machines that pass over crop rows and take photos. A deep learning computer program analyzes the images to distinguish weeds from crops. Then, the lasers zap the weeds to kill them. The machine’s computer program also allows farmers to prioritize types of weeds, such as smaller plants that are close to the crop that may be difficult for humans to see and eliminate, for the lasers to target. ..."

From the abstract:

"BACKGROUND

Herbicides are the primary weed management method for processing vegetable growers, but challenges such as limited chemical options, herbicide resistance, crop injury risks, regulatory changes, and shifting consumer preferences are driving interest in nonchemical alternatives like laser weeding. In 2024, three research trials in New Jersey and New York evaluated the effectiveness of laser weeding using a commercial unit and comparing it with pre-emergence- and postemergence-applied herbicides on beet (Beta vulgaris L.), spinach (Spinacia oleracea L.), and pea (Pisum sativum L.).

RESULTS

Across all trials, laser weeding was as effective as or superior to S-metolachlor, bentazon and phenmedipham herbicides applied at label rate in controlling erect annual weeds, including common lambsquarters (Chenopodium album L.) and common ragweed (Ambrosia artemisiifolia L.). However, laser weeding was less effective on purslane (Portulaca oleracea L.) and annual grasses in New York because of sequential emergence patterns and protected meristems, respectively. Compared with untreated controls, laser weeding reduced weed cover by ≥45% and density by ≥66%, resulting in ≥97% less weed biomass by the season's end. In addition, crop stunting did not exceed 1% and crop biomass increased by ≥30% when laser weeding replaced herbicide applications.

CONCLUSIONS

These findings demonstrate that multiple laser passes can control weeds without damaging crops, leading to higher yields than conventional herbicides. Further research is needed to optimize laser weeding across different environments and weed species, and to evaluate commercial units with increased laser capacity and faster processing speeds."

Lasers match common herbicides at zapping East Coast weeds | Cornell Chronicle

Deep learning-based laser weed control compared to conventional herbicide application across three vegetable production systems (open access)

Carbon Robotics Autonomous LaserWeeder™ demonstration unit in operation in Geneva, NY.