Many Amazonian peoples have a profound effect on rain forest structure and species composition through a process called succession management, by which they clear and manage forest fallow areas in which grow planted and naturally-established species. The Runa Indian community (in Napo Province, Equador) live in dispersed settlements at low density. Unlike Amazonian people living in concentrated settlements, they are not under strong pressure to intensify succession management in order to concentrate forest resources. Manipulation of succession, even under such low density conditions, increases the species diversity of larger trees. Planted tree crops accounted for between 8% and 19% of trees in this size class, and protected secondary species for between 6% and 16%. The distribution of many species, however, was not the result of conscious management decisions, although seedling establishment may have been altered by agriculture. It is possible that succession management in this Runa community could be further intensified to increase the proportion of useful planted and protected species. Nevertheless, resources present in Runa managed fallows provide significant amounts of food, construction material, and firewood as well as medicinal plants and other needed household items.
Rainforests have been altered throughout history, first by indigenous farming practices and now by state and private sustainable agriculture programmes. Swidden type agriculture, practised by indigenous people, converted many forests to fallows. Fallows and high forests are different in the total number of species in a sample area. These numbers tell us that fallow forests represent indigenous reforestation, insofar as species richness of high forests are being replaced by an equivalently rich secondary forest. Whilst it is undeniable that the indigenous farming practices are less destructive than state practices, the number of most important species between fallow and high forests are significantly and predictably different. If modern states cannot protect the remaining indigenous populations, they may lose an abundance of knowledge relating to resource use, management, and biological and ecological diversification.