Keeping squirrels off mushroom logs?

I've grown mushrooms on logs for many years, and only occasionally would have some minor losses due to squirrels nibbling off the bark. This past spring however I put up around 1500 red oak logs and the squirrels have just been relentless. I blame myself for not keeping a closer eye on my piles; by the time I noticed they had about 100 logs nearly destroyed. They are attacking my red oak fire wood with the same veracity, so I know it has nothing to do with with mushrooms, I guess they just like to chew the bark...

I'm about at my wits end. I have been able to pop a few with a pellet gun and a few stepped into my rat trap, but they are smart and numerous. I'd really like some way to keep them off the logs rather than trying to pick them off one by one. I did try mothballs, but that doesn't seem to bother them. Any advice appreciated!  

Maybe the squirrel just figured out what yummy treats mushrooms are.

My suggedtion would be to put the mushroom logs in cages or put the squirrels in cages.

Re. meddlesome squirrels, I can relate, so much for most of the seeds I intended for autumn harvest in Oct./Nov.

Problems like this I find are often easiest solved by the addition of a dog. Not just any old dog but one that watches over a place and will chase off wildlife. Not a sure fire stop to the problem, but something that could deter squirrels from being in the area.