Birch bark is an amazing material. Not only is it functional, it's remarkably beautiful. I compared my lovely wife to inner birch bark in a poem, and she swooned. It really is that pretty.
My friends April and Jarrod turned me on to the possibilities of birch bark. They are both amazing artists with natural materials, and they have a wonderful family. Check out their website http://www.woodspiritgallery.com/
These projects are all fast and simple. They don't require the high quality bark that baskets and canoes do. You need some bark, a scissors and a microwave.
Step 1: Harvesting Birch Bark
Harvesting bark is easy and fun. July is a good time of year to harvest bark in Northern Wisconsin. Done correctly and in moderation, collecting bark doesn't kill the tree.
Make a vertical incision in the bark with a sharp knife. Make the incision several feet long. You'll should see a distinct boundary between the outer and inner bark when you pry a bit of the bark away. When conditions are right, the bark practically pops off the tree.
Work the knife or your finger between the inner and outer bark and peel if off. See Jarrod's blog about harvesting huge pieces of bark for canoes to see pictures. http://www.jarrodstonedahl.blogspot.com/2011/07/birch-bark-canoe-construction.html
You won't need anything that big for these projects. Roll the bark vertically and inside out. You can see this done in Jarrod's picture with the caption, "first tree peeled". Tie rope around the bark to keep it rolled up, or if there is basswood nearby, you can use basswood bark instead.
Step 2: Delaminate the Bark
Birch bark has many layers. When the meristem divides, the inside layer turns into wood, and the outside layer becomes bark. Each layer of bark corresponds to one growing season. Each layer of bark that you see in the picture is actually several layers. An individualy years' growth is thinner than paper, delicate and translucent. The bark will split along some layers more easily than others, as seen in the photo. You can use this to your advantage to delaminate the bark to thickness that you want. Try bending the bark sharply near one edge to see where the the natural delamination layers are.
Step 3: Rough Shaping
So, you want a birch bark bracelet, eh? Cut the bark to rough shape, peel the bark to the desired thickness and then draw the shape of your bracelet on the bark. The bark will bend inside out when you heat it in the microwave in later steps, so if you won't remove all your drawing lines, draw on what was the outside of the bark.
You see the inner face of the bark in the photo before cutting. The white outside face is face down. I've actually peeled the outer several layers of bark off this piece already. You see the other side of the bark in the cut photo.
Lightly burnish the edges of the final shape to round over the cut edges. It will make your bracelet look better.
Step 4: Heat and Shape the Bracelet
Put your piece of bark in the microwave on high power for 15 to 45 seconds. As it heats, you'll see it start to curl. Take it out and check it after 15 seconds. Continue heating it until it's warm and pliable. Form a ring smaller than your wrist, and flatten it into an oval. Let the bark cool, then put it on your wrist. Birch bark bracelet complete!
Step 5: Other Ideas
You can make many more items from bark. Make a smaller ring and use it as a napkin ring. Make a shorter, more gently curved piece. Drill holes in it and insert a stick to make a different kind of napkin holder, or use it to hold your pony tail in place. Don't drill the hole through a lenticel that extends to the edge of the piece of bark. The lenticels are the darker lines that you see in the bark. They are weak, and the bark can split along the lenticel.
The pictures don't do the bark justice. It looks amazing. I've made woven birch bark coasters and coasters simply cut from a piece of bark. I've sent birch bark post cards though the mail. I've used bent bark in an art project to show the paths of the sun at the summer and winter solstice. I don't view any of these objects as permanent. They'll break, or stain over time. Just make some new ones, and you're back in business. Birch bark is remarkable stuff.