Personally, I think bark burns just fine as long as its dry. Some barks such as birch, which native americans and a few craftsmen today, make canoes with are actually waterproof. Makes splitting birch to season it vital otherwise all the water inside can't get out. Many people feel oak really needs to be seasoned 2 years to be really dry. I wouldn't be surprised if the ice under your bark is from moisture still coming from inside the log. Having it exposed to the rain and snow of winter doesn't speed the seasoning process either if your trying to burn it now.