I wish i could see a tree,
or running water.
This page is a project in progress. The goal is to write a set of tree processing functions in Perl, Python, Java, languages, along with several articles on trees of mathematics of computation. Possibly Haskell and Scheme versions will also be included by contributors. The Perl version is mostly done. See here for a list of the functions: Perl-Mathematica Perl module.
Note: this project is currently dormant.
Here are some expositions on trees oriented towards Mathematica:
Here is a Mathematica notebook that contains over 20 functions on trees associated with this study: TreeFunctions.nb
Disclaimer: Mathematica is a trademark and product of Wolfram Research Incorporated. This project is not affiliated with Wolfram Research Incorporated.