>> I am often asked about the number of species of trees in the world.
>> Who knows wherer I can find this information ?
>> Thank a lot
Going from 250,000 plant species altogether (fairly conservative
estimate), and extrapolating from 10 percent trees in some floras, you
get 25,000 tree species in the world.
Caution: a lot depends on what you call a tree, and the boundary between
shrub and tree depends on who you're talking to.
Another caution: my percentage might be way off. It's based on East
Africa, and might not be valid elsewhere.
I'd be interested in other opinions!