There’s a lot riding on farmers’ ability to fight weeds, which can strangle crops and destroy yields. To protect crops, farmers have two options: They can spray herbicides that pollute the environment and harm human health, or they can hire more workers. Unfortunately, both choices are becoming less tenable. Herbicide resistance is a growing problem in crops around the world, while widespread labor shortages have hit the agricultural sector particularly hard. Now the startup FarmWise, co-founded by Sebastien Boyer SM ’16, is giving farmers a third option. The company has…