The Beaker "Weed or Plant" App

Inspired by a new phone app I saw that can tell you - allegedly- whether a plant is a weed or a "good" plant.

The Beaker Plant or Weed app has a Red/Green traffic light system. Green is "all plants are good in the right place". 

Red is "GIANT HOGWEED - Strike by night - they are defenceless. Don't let them kill you with their hogweed hairs. KILL WITH FIRE."

It's a simple system. But effective.