Depicting light and the play of shadow has long been a concern for painters. Generations of painters before the Impressionists used neutral tones and black and grays for shadows. The Impressionists abolished this way of creating shadow by using color instead. Many artists employed purples, yellows, and other colors to suggest colored shadows and reflected light. In so doing, they heightened the coloristic effects that captured their attention when painting in the open air. Hassam uses a range of dark greens and even blues to suggest shadows beneath the tree or at the edges of boulders.