A simple but neat resource that will help you build up your own notes on the useful flora of your campaign world. Each card has a simple line drawing of a plant or part of one, and space for your own notes.
It is left to you to name them and work out their uses, magical and mundane. Unless you use the 'comment' feature (and preferably same the annotated file under a different name) you will have to print them out and then write your comments.
The drawings are neat and show the parts of a plant that a herbalist or healer might be interested in - leaves, roots and so on. A glance through a herbal (or a bit of online research) should suggest some uses for these plants, and how to process them; and then you will have to add any rules mechanics necessary for your system of choice.
The nice thing about these is, once you have decided what they are and what they do, you can show them to your players to give them an idea of what they are looking for when out foraging. A good tool especially for all the non-botanists out there! Even if you do know a bit about plants, it's nice to have something different in your fantasy world from the ones growing around you!