Harvest index
The fraction of total biomass removed in a harvest, used to estimate extraction and residue in managed forests.
The harvest index expresses how much of a stand's biomass leaves the site when it is cut. The remainder — roots, stumps, tops, branches and foliage — stays behind as residue and eventually decomposes or burns.
Its value depends on what is removed and how thoroughly. A stem-only harvest in a conventional logging operation leaves far more residue than whole-tree harvesting for bioenergy, where branches and tops are also taken. Species, equipment and market demand for small material all shift the index.
In carbon accounting the index determines both the immediate removal and the subsequent decay flux. Using a generic value for a specific operation is a frequent source of error, and it is one that verifiers test against harvest records and imagery.
Frequently asked questions
Why does whole-tree harvesting matter?
It removes material that would otherwise return to the soil, reducing the residue pool and often increasing nutrient export.
How is the index verified?
By comparing declared removals with transport records, mill intake data and remote detection of residual slash.