The Cecil County maple had been designated the state's largest tree since 2006, a statement from the department said.
The state honor now goes to an American sycamore in Montgomery County.
The new title-holder stands in the C&O Canal National Historical Park, about 300 feet from the Potomac River, and is publicly accessible.
The title is bestowed by the Maryland Big Tree Program, run by volunteers from the Maryland Association of Forest Conservancy District Boards.
Using a points system developed by Maryland's first state forester, Fred Besley, the program started in 1925 recognizing county- and state champions in every species. To date, the program has listed more than 130 state champions and more than 2,250 living "big trees" in Maryland.
The American Forestry Association (now called American Forests) established a nationwide version of the program in 1940, using Besley's formula.