Jason Richard Swallen

Jason Richard Swallen (May 1, 1903 – April 22, 1991) was an American botanist who specialized in grasses. He was curator of the Division of Grasses and later head of the Botany Department at the National Museum of Natural History.

Born in Alliance, Ohio, Swallen graduated from Ohio Wesleyan University (AB 1924) and Kansas State Agricultural College (MS 1925). He spent two summers at the Michigan University Biological Station, then in 1925, was a junior botanist at the US Department of Agriculture, serving under the USDA's chief agrostologist A. S. Hitchcock and after Hitchcock's sudden death in 1935, Agnes Chase.