Yes. It was on. I tried turning it off, no luck. Then I tried picking up the brush, painting in a masked area with auto mask off, copy/pasted and had the same problem.
I'm guessing I have to create the mask with the auto-mask off... but that would prove too timely for such intricate trees.
Do you think I have to make the whole mask with auto-mask off?
Kelly, I think what you are trying to achieve with a 'mask' is not possible in Lightroom. It is more a job for Photoshop.
In Lightroom there is no concept of "Masks" as it is in Photoshop where you can create an exact mask right down to a specific pixel detail. and save that mask!
The 'mask' you see in Lightroom is better called an "Overlay" to indicate where you have brushed. 'Auto Mask' will allow you to brush along edges where tones vary in level, but the overlay mask you see is not 'permanent'- it would change from one image to the next (when pixels vary, even slightly, in levels). And as you have found- without Auto Mask- the brush overlay is indiscriminate and affects any pixels under the brush stroke.
So- a job for Photoshop!