Pattern matching, acceptance, and parsing algorithms on node-labeled, ordered, ranked trees (‘tree algorithms’) are important for applications such as instruction selection and tree transformation/term rewriting. Many such algorithms have been developed. They often are based on results from such algorithms on words or generalizations thereof using finite (tree) automata. Regrettably no coherent, extensive toolkit of such algorithms and automata existed, complicating their use.

Our toolkit FOREST FIRE contains many such algorithms and automata constructions. It is accompanied by the graphical user interface (GUI) FIRE WOOD. The toolkit and GUI provide a useful environment for experimenting with and comparing the algorithms. In this tool paper we give an overview of the toolkit and GUI, their context and design rationale, and mention some results obtained with them.