Herbicide resistance has quietly become one of the most expensive problems in modern row-crop agriculture. Drones equipped with high-resolution cameras and machine learning models are changing that equation by finding resistant weed patches early and precisely, before they spread across an entire field. A Problem That Keeps Growing Every SeasonWeed scientists have been tracking herbicide resistance cases for decades, and the numbers only move in one direction. The International Survey of Herbicide-Resistant Weeds currently lists 548 unique cases worldwide, spanning 275 species across 156 dicots and 119 monocots. What’s Actually Happening Inside the Detection PipelineWeed mapping systems generally follow the same three-stage pipeline: data acquisition, data processing, and decision-ready mapping output.