In a shady, parklike setting near the DuPage River is one of the oldest, loveliest, and most influential collections at The Morton Arboretum: the Elm Collection.
It is one of the most extensive collections in the world of plants from the elm family (Ulmaceae). In addition to elm trees (in the genus Ulmus), the collection includes related plants such as hackberry (Celtis), thorn-elm (Hemiptelea), and zelkova (Zelkova).
Most of the tree species in the collection are elms, tall trees with arching branches that give them a vase-like shape. That shape is familiar to many residents of older cities who may remember when American elms (Ulmus americana) lined many streets and arched overhead. Since the 1930s, Dutch elm disease has killed many millions of those elms.
The Arboretum’s elm collection has played a role in the response to that devastating disease. The collection includes species from all around the world, some of which are naturally resistant to the disease. Arboretum researchers used the collection to begin an elm breeding and distribution program that has introduced several cultivated varieties of elms that resist the disease.
The Elm Collection was started in 1926, making it one of the oldest Arboretum collections. It covers more than 5 acres near the river, which is suitable habitat for elms; many species come from riversides and bottomlands. There are more than 75 different kinds of trees here, with a total of 165 specimens, many of them tall, mature, spreading shade trees. They make the Elm Collection an especially welcome refuge of shade in the warm summer months. If you visit to take a break in the shade, rest on a bench that artfully celebrates the trees’ graceful qualities.
The Arboretum’s collection includes many rare Asian elm species, which have made important contributions to the breeding program to develop disease-resistant elms. Through the Chicagoland Grows® Plant Introduction Program, the Arboretum has successfully introduced five new cultivated varieties, or cultivars, which together have enabled the elm trees’ return to the landscape. These include the Accolade™ elm (Ulmus ‘Morton’), the Triumph™ elm (U. ‘Morton Glossy’), the Vanguard™ elm (U. ‘Morton Plainsman’), the Danada Charm™ elm, (U. ‘Morton Red Tip’), and the Commendation™ elm (U. ‘Morton Stalwart’).
The Elm Collection is a Nationally Accredited Collection of the Plant Collections Network, one of six accredited collections at the Arboretum. The Plant Collections Network is administered by the American Public Gardens Association in collaboration with the USDA Agricultural Research Service.