sqlamp is an implementation of Materialized Path, an efficient algorithm for working with hierarchical data structures. sqlamp uses (and depends on) SQLAlchemy. Materialized Path is a way to store (and fetch) trees in a relational databases. It is the compromise between Nested Sets and Adjacency Relations in respect to simplicity and efficiency.
OpenTreeMap is software for collaborative, geography-enabled urban tree inventory. The software enables the public, organizations, and governments to collaboratively contribute to an interactive and dynamic map of a community’s tree population. Users can search for trees, add trees to the system, edit existing tree information, or upload tree photos. The system automatically calculates a tree's ecosystem benefits based on its species and diameter. OpenTreeMap can be used in a single municipality or to cover a broader geographic region with many communities, anywhere in the world. This software also exists as a subscription-based system.