I made candle holder covers with the white birch bark I picked up. Let me show you how I did it. I washed and dry the bark and soaked it so it would become pliable. Wash and dry the candle holders too.
Apply acrylic gel medium to the outside of the candle holder.
Measure against the side of the candle holder, then cut. Adhere bark to glass, then tie. Let dry for 24 hours before removing the tie. This is the hardest part. Plop a candle in and light. Piece of cake.