Pray was president of the American Society of Landscape Architects from 1914 to 1918 and held the post of chairman of the Department of Landscape Architecture at Harvard University.

[1] Pray graduated from the Chauncy Hall School in 1894 and Harvard College in 1898.

He married Florence Mabel Nichols on October 30, 1901 in Buffalo, and later had a son named Benjamin Sturgis, who also graduated from Harvard in 1925 and lived in Thayer Hall during his freshman year, and a daughter, Frances Motley, named after his mother.

In 1908, Pray succeeded Frederick Law Olmsted as chairman of the Department of Landscape Architecture at Harvard University (1908-1928).

Pray was a patron of the Lowthorpe School of Landscape Architecture in Groton.