Wood structure is like a bundle of drinking straws. Under a microscope the end grain of wood you can see the many tubes and vessels that are bound together to form the wood structure. These ‘drinking straws’ were used to transport water and nutrients up and down the tree when it was growing. We know that water can enter the end grain of wood 1000 times quicker than water entering the side (tangential or radial) face as the water is drawn up the ‘straws’ by capillary action.

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