I?m trying to keep treatments natural,
There are other non-chemical treatments than powdered sugar. You could try oxalic acid, thymol, or formic acid, to name some. I'm not experienced enough to know what would be best for your area, so you might want to do some research on them and see what you think you'd like to try. I used Mite Away Quick Strips (a formic acid treatment) last year on my hive that did not abscond, and it worked for me. I would think you are going to want to do something pretty quick though, since the situation seems to be rather advanced based on what you are seeing.
