Plant stats requested

[C. Richter]

For a semi-popular article on herbs I need figures (with refs) for 
the following: 

   Estimated no. of species in plant kingdom (500,000?)

   No. of species utilized by man for any purpose, including 
   food, medicine, ornament, etc. 

   No. of species analyzed either partly or relatively throughly 
   for chemical composition.

   No. of compounds known to be found in plants.  

My latest figures for these are old (70s); recent estimates would be 
appreciated. 

Conrad Richter
Richters 
Canada