ROCK STARS Wood's Strength Knots Knots can affect wood's strength. Take a look at "Wood Parts and Anatomy: Taking a Closer Look at Wood" lesson to review how knots are formed. If you want very strong wood, look for wood without knots. Knots significantly reduce wood strength. This doesn't mean that wood with knots is very weak -- knots just reduce the strength. Knots reduce strength because they are a change in the direction of wood growth. When wood grows normally, all the cells grow in the same direction, but a know has cells that grow in a different direction. Knots interrupt the cells, so the cells become weaker! Wood grain also has an effect on wood's strength. Wood Grain

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