Question
what is the ratio-native plants(not endangered)to natives(endangered)to introduced pests to introduced plants(not pests)?

Can be in any form preferably a graph or ratio!
Thanx

Answer
Riah,

I don't know.

The answers would depend on what specific area you are interested in and whether or not it has be studied.

In my area, I would start here:

http://www.oda.state.or.us/Plant/plant_conservation/

For what it's worth
Mark in Portland Oregon