Working with multiple masks in color section?

Hello,

I have landscape footage, were I want to make color adjustments in 3 different regions
1. Hill/Mountains
2. Water
3. Forrest

In the COLOR window/page I can add one polygon mask and do the color adjustments.
If I add a second polygon mask I'm not able to do individual color adjustments for this second polygon mask.

What I have to do in the COLOR window/page in order to generate 3 separate polygone mask with inidvidual color adjustments for each?

Add additional masks in new nodes.

@Jim Simon

Thanks!

I was successful by adding parallel notes to add new masks with independet color adjustments.