Sarg.

Charles Sprague Sargent (April 24, 1841 – March 22, 1927) was an American botanist. He was appointed in 1872 as the first director of Harvard University's Arnold Arboretum in Boston, Massachusetts, and held the post until his death. He published several works of botany. The standard botanical author abbreviation Sarg. is applied to plants he identified.

Sargent was the second son of Henrietta (Gray) and Ignatius Sargent, a Boston merchant and banker who grew wealthy on railroad investments. He grew up on his father's 130-acre (53-ha) estate in Brookline, Massachusetts.

He attended Harvard College, where he graduated in Biology in the class of 1862. Sargent enlisted in the Union Army later that year, saw service in Louisiana during the American Civil War, and was mustered out in 1865. He traveled in Europe for three years.

Having returned to his family's Brookline estate, "Holmlea", Sargent took over its management as a horticulturist, influenced by his cousin Henry Winthrop Sargent and H. H. Hunnewell of Wellesley. Under his direction, the family estate became a landscape without flower beds or geometric arrangements, but rather a recreation of nature with winding lanes, overhanging branches, and a profusion of trees and shrubbery.

When in 1872 Harvard University decided to establish an arboretum, Prof. Francis Parkman, at that time a professor of horticulture at Harvard's recently established Bussey Institution, probably suggested his young neighbor Sargent for the position. By the end of 1872, Sargent became the first Director of the Arnold Arboretum, a post he held until his death. He was also Director of the Botanic Garden in Cambridge.

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