Notes on Mail Link with Gmail

Somehow the Notes on my Mail is linked to my Gmail account (don't know how). Notes on Mail expands to 2 subfolders: "On My Mac" and "Gmail". Does anyone know how I can de-link the Notes from Gmail so I will not see the Gmail subfolder in Notes?

Reason for this request is that I sync my Blackberry to MAC using Blackberry Desktop Software. The Gmail subfolder in Notes causes confusion/issues for syncing the Notes between MAC and Blackberry resulting in duplicate notes on BB after each sync which is extremely annoying.

I thank you in advance for your help.

MAC 10.6.8

Mail 4.5

BB Desktop Software 2.1.3