An estimated 16,000 tree species occur in the Amazon rainforest. This figure describes the estimated number of tree species across the wider Amazon region, not the number found in every individual forest plot or hectare. It illustrates why the Amazon is considered one of Earth’s richest terrestrial ecosystems.
The estimate comes from large-scale botanical and ecological research that combines forest inventories, herbarium records, and statistical modelling. Individual sites can contain extraordinary concentrations of trees: one study in Ecuador reported more than 1,100 tree species within a quarter-square-kilometre area. Such local richness is unusual even within tropical forests.
The number should not be confused with the total number of Amazonian plant species. The region contains hundreds of thousands of plant species or recorded plant taxa, including vines, palms, shrubs, epiphytes, and herbs. Nor does 16,000 mean that every species is common. Many Amazonian trees are rare, occur in limited areas, or remain difficult to identify and catalogue.