What does it take to paint a wildflower that blooms for a single day in a deep forest? For Mary Vaux Walcott, it involved spending the entire day outdoors with her paintbox to capture the shape, movement, and color of delicate petals and leaves. Her technique involved precise attention to detail, light, and perspective, and she was an intrepid scientist as well as a generous benefactor to the Smithsonian Institution. Walcott's celebrated watercolors, first published in five oversized volumes in 1925, introduced the public to the beauty and diversity of North American plants, and this catalog presents 250 of her superb illustrations in vivid reproductions.