Step-by-step oil painting tutorial of an old Oak tree by George Allen Durkee. The essence of this demonstration is to achieve color harmony by adding one particular color, called the mother color."The "ghost tree" in this demonstration emerges from the fog. There is a hush that subdues sound, color and light. Everything becomes quiet; subtle color merges with subtle color. The grays are not black and white, nor are they made pastel by simply adding white paint to color; instead, each color in the painting takes on some of the mother color."