How do I stop woodpeckers from eating my cedar siding?

I have borer bees (benign and helpful) living in the cedar tops of my garage doors. We coexist happily. Now a downy or hairy woodpecker is pecking huge holes in the cedar in order to eat the bees. I have chips of wood the size of small kindling lying on driveway floor each morning.Soon there will be neither bees nor wood framing left. i notice similar damage to black birch trees that harbor insects...5" gouges.