Pomology Charles were prominent in Pomology and Horticulture, producing "The Fruits and Fruit Trees of America" (1845). The introduction of new varieties required exact depiction of the fruit so that plant breeders could accurately document and disseminate their research results. Since the use of scientific photography was not widespread in the late 19th Century, USDA commissioned artists to create watercolor illustrations of newly introduced cultivars. Many of the watercolors were used for lithographic reproductions in USDA publications, such as the "Report of the Pomologist" and the "Yearbook of Agriculture". Today, the collection of approximately 7,700 watercolors is preserved in the National
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