Mary Agnes Meara Chase (April 29, 1869-September 24, 1963) was an American botanist. She specialized in the study of grasses and conducted extensive field work in South America, often personally funding her research trips, as it was considered inappropriate for women to conduct such work. Chase joined the Department of Agriculture in 1903 as a botanical illustrator and eventually became Scientific Assistant in Systematic Agrostology, 1907; Assistant Botanist, 1923; and Associate Botanist, 1925. In 1935, she became Principal Botanist in charge of Systematic Agrostology and Custodian of the Section of Grasses, Division of Plants, United States National Museum.