Old-growth forest

The primary forest of human influence not touched forest ( " jungle " ) is referred to, thus an ecological climax community. The classification as 'untouched' is dependent on the undisturbed development time. For example, the soils of the Amazon have been found traces of human working on about ten percent.

A secondary forest or, after massive intervention, initially a secondary vegetation with varying degrees of changes in species composition develops after human intervention, such as road construction, logging, slash and burn, floor mounting, etc.