Researchers trained a neural network to recognize what's making plants sick

You're working in the garden when you notice your tomato plant is stunted and wrinkled. What is your next step? A team of researchers from Penn State University and the Swiss Federal Institute of Technology in Lausanne (EPFL) believes you should reach for your phone. They are building a free app called PlantVillage that can recognize plant disease from a mobile phone photo. Behind the app, expected to be available in early 2017, is a database of 150,000 photographs of diseased plants--a number the team intends to grow to three million.