Once a tree with a large trunk was chopped down, it was allowed to get dry. This process used to take minimum of three to four months. When the tree was completely dry, its bark was removed using primitive tools. The bark was procured by cutting it in long stripes from the tree trunks. These cut parts were then stitched together using fibers made from tree roots.
Once this was done, an internal lightweight structure was made inside the bark using any type of light wood. This process was the main difference between a skin boat and a bark boat. In a skin boat, the internal wooden frame was built first and then an animal skin was stretched over it. However in a bark boat, the other bark was made first and then the internal wooden frame work was done. One more difference between the two types of boats was that skin boat would get its strength from the internal wooden frame work, whereas a bark boat would get most of its strength from the outer bark.
Bark boats were made from the bark of different types of trees. However, they were mainly made from birch trees that are found extensively in Europe and North America. Some of the bark boats found in Pacific Northwest are up to 14 meter long. However, both skin and bark boat are supposed to be known as light and flimsy vessels suited only for inland water bodies and are not meant for sea. Also, though a bark boat is thicker and more reliable than an animal skin boat; both the boats have high and equal probability of getting their covers punctured.

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