Problem on Color Page

After trying to balance the colors and lighting unsuccessfully on a clip with lots of movement and lighting variability, I decided to divide the clip into two and make different adjustments for each. I had already created a node tree that I wanted to keep for the first clip and remove for the new second clip. But when I delete the nodes in the second clip it deletes them from the first clip as well. The clips are showing up as separate on both the edit and color pages and I don't have both selected when doing the delete. Is this perhaps a bug or what else might I be doing wrong?

Are you using Remote Grades?

And then, do you know about keyframing in the Color page?