SExI-FS 2.1.1 was available to download from the developer's website when we last checked. We cannot confirm if there is a free download of this software available. This free program is an intellectual property of ICRAF. We recommend checking the downloaded files with any free antivirus. This free PC software is compatible with Windows 7/8/10/11 environment, 32-bit version. SExI-FS lies within Home & Hobby Tools, more precisely Bookkeeping-Cataloging. The most popular versions among the program users are 2.1 and 1.0.
From the developer:
The SExI Forest Simulator focuses on tree-tree interactions in a mixed multi-species agroforest. The high level of structural complexity of such traditional agroforestry systems defies classical forestry approaches when it comes to optimizing management practices. To cope with this complexity, farmers have adopted a tree-by-tree management approach, which is closer to gardening than to any usual tropical forestry or estate crop management model.
You may want to check out more software, such as TOPO!, CATVids or My Checkbook, which might be related to SExI-FS.