Whether you are looking at the Amazon, Congo or the rainforests of South-east Asia, a study has shown that just 2% of species account for 50% of trees in all systems.
In numbers, this means, that of the roughly 800 billion trees on earth, roughly half come from around 1000 species, while the other half are made up of a further 46,000 different species.
While this could have many negatives, it suggests that accurately modelling may well be easier, as the forests would likely survive if just these 1000 trees were to live (this is not to say that we do not care, the 46,000 trees that might be lost, would likely cause many other extinctions, and who is to say that these trees, do not hide medication that would one day be useful to humanity?