White Oak has been time tested and proven to stand up well to the harsh conditions of weather. This wood has traditionally been used for ship timbers, wagon wheels, barrels, exterior doors, and outdoor furniture such as swings and rockers. The hardness resists dents, scars, and scratches. The cells are sealed with a tylosis membrane which keeps moisture from entering. In fact, the U.S.S. Constitution sailing ship, which was made of White Oak in the 18th Century is still floating in Boston Harbor. There are still hundred year old White Oak swings in antique stores. Oak that has been kiln dried down to 7-8% moisture content ensures there will be no warping when placed out in the weather.