American Elm Restoration

History of the American Elm

The American Elm was once the street tree of choice for America's main streets. This beautiful native tree is hearty and adaptable to a wide range of conditions found in cities. The most visible and well-known American Elms in the District are growing on the National Mall between the U.S. Capitol Building and the Washington Monument.

Dutch elm disease (DED) devastated many stands of historic elms across the country including here in the District. As many as 100 million elms have succumbed to DED in the U.S. since its introduction from Europe about 75 years ago. DED remains an ever-present risk, with an infection rate of 4% to 6%, affecting over 200 trees every year.

Our Work with American Elms

Since 2003, Casey Trees has been working to restore the local American Elm population by planting disease-tolerant cultivars such as Jefferson, New Harmony, Princeton and Valley Forge in historic and designated streetscapes across the District. The District’s Urban Forestry Administration (UFA), the entity charged with planting and maintaining street trees, identifies the locations for these elms to be planted. We purchase, plant and water the trees with our own funds. The Casey Trees Summer Crew assists in watering and caring for the elms that our staff plants in the winter.

We have planted and cared for more than 1,750 American Elms in the District since the inception of our American Elm Restoration program. For the Winter 2010-11 season, we planted 100 more Valley Forge elms in Wards 1, 3, 5 and 6. You can find all of the Casey Trees-planted trees and designated American Elm corridors on the Casey Trees Map.

Casey Trees