Sour Gum, Black Gum, Pepperidge or Tupelo. (Nyssa sylvatica) A forest tree up to no feet high; in wet lands. Wood pale, very strong, tough, unsplittable and heavy. A cubic foot weighs 40 lbs. Used for turner work, but soon rots next the ground. Leaves 2 to 5 inches long. Noted for its brilliant fiery autumn foliage.