I usually leave those alone and go find another tree, but I have that luxury here where I'm at.
I pass up some pretty good trees to get to the better ones. Until I had guys start asking for the "snakey" staves so I decided that maybe I need to start taking a closer look at all those crooked trees I've been passing up.
When I have a stave that has big knots or limbs in it, I just try to split in between them and get the clean piece out of it. Then the rest becomes fire wood.