Massachusetts State Tree
American Elm (common name) Ulmus americana (scientific name) Overview The American elm was a popular tree in parks and along avenues prior to 1930. It has been described as "vase-shaped" with upright, arching branches forming an open space beneath its high canopy. This tree is also known as white elm, water elm, soft elm, and Florida elm. Both Massachusetts and North Dakota chose American elm as their state trees in the 1940s--just as these trees were beginning to die in alarming numbers. The Dutch elm disease, an introduced fungal pathogen, originated in Asia, but was first described in the Netherlands. Spreading from east to west, the disease devastated the American elm population. Trees in the southern part of the elm's range have been more likely to survive. In high-profile areas, some mature American elms have been preserved. Intensive research has focused on breeding resistant plants, either by hybridizing American elm with naturally resistant elm species, or by selective breeding of elms that have shown innate resistance. Close-up STATUS Official PHYSICAL DETAILS American elm is a large, deciduous, fast-growing, long-lived tree with arching branches. It normally reaches 40 to 80 feet (12-24 m) in height at maturity, but can grow much larger. Its rough, textured, oval-shaped leaf has an asymmetrical base and saw-toothed margins. Its flowers are green and insignificant. Fruits are winged and discus-shaped, with a fringe of hairs around the edge. Height: 100-200 ft (30-36 m) Diameter: 48-60 in (122-152 cm) Bark: dark gray, deep furrows Seed: flat pod almost 1 in (2.5 cm) long and 0.5 in (1.7 cm) broad, with a circular wing surrounding the single seed Leaves: double-toothed, 2-5 inches (5-10 cm) long, 1-3 in (2.5-7.5 cm) wide LIFESPAN American elm is a fast-growing, long-lived tree. Trees in areas unaffected by Dutch elm disease can live for several hundred years, but more commonly reach 150 to 200 years of age. HABITAT American elm grows in climates varying from warm and humid in the southeast to cold and dry in the northwest. Average annual precipitation ranges from scarce to plentiful across the tree's range. IMPORTANCE TO LIVESTOCK AND WILDLIFE Although American elm is not considered a preferred food source for grazing animals, deer, rabbits, and hares will occasionally browse the leaves and twigs. A number of small birds eat the seeds. Mice, squirrels, opossum, ruffed grouse, northern bobwhite, and Hungarian partridge eat the flower bud, flower, and fruit. OTHER USES AND VALUES Before the advent of Dutch elm disease, American elm was prized as a street ornamental in numerous cities in North America. The wood of American elm is moderately heavy, hard, and stiff. It has interlocked grain and is difficult to split, which is an advantage for its use as hockey sticks and where bending is needed. It is used principally for furniture, hardwood dimension, flooring, construction and mining timbers, and sheet metal work. Some elm wood goes into veneer for making boxes, crates, and baskets, and a small quantity is used for pulp and paper. REPRODUCTION American elm seed production may begin as early as age 15, but is seldom abundant before age 40. When mature, American elm is a prolific seed producer. Trees as old as 300 years have been reported to bear seed. The tree will reproduce fairly vigorously by stump sprouts from small trees. Large trees 150 to 250 years old seldom sprout after cutting. SITE CHARACTERISTICS American elm is most common on flats and bottomlands throughout its range but is not restricted to these sites. It is also found on many of the great soil groups within its range. American elm grows best on rich, well-drained loams. LOCATION/ELEVATION American elm is found throughout eastern North America. Its range is eastern and central Canada, south to extreme eastern Montana, northeastern Wyoming, western Nebraska, Kansas, and Oklahoma into central Texas, east to central Florida, and north along the entire east coast. TRIVIA Legend maintained that General Washington took command of the Revolutionary Army under a particular elm, called the "Washington Elm," on Cambridge Common in Cambridge, Massachusetts. The story became part of American popular culture as early as the 1830s and was made famous in 1876 by a fictitious "eyewitness" journal, The Diary of Dorothy Dudley. The tree stood in Cambridge, Massachusetts, until its death in 1923. Washington took command of the army in Cambridge on July 3, 1775, but there is no documentation to indicate that the event took place under the elm tree. When relatively isolated from other elms, American elm trees may be able to survive Dutch elm disease. Such examples exist in Central Park and Tompkins Square Park in New York City, in Independence Square and the Quadrangle at the University of Pennsylvania in Philadelphia, and on the campus of the Pennsylvania State University. This university is believed to have the largest remaining group of American elm in the country. Because the elm shaded and gave its name to so many streets across the country, Elm Street is generally believed to be the most common street name in the United States.
	Click to enlarge an image American Elm American Elm Leaves American Elm Seeds American Elm Bark Dutch Elm Disease American Elm Distribution Map (pdf) CLASSIFICATION Kingdom: Plantae Subkingdom: Tracheobionta Superdivision: Spermatophyta Division: Magnoliophyta Class: Magnoliopsida Subclass: Hamamelididae Order: Urticales Family: Ulmaceae Genus: Ulmus L. Species: Ulmus americana L.
	Sources: U.S. Forest Service U.S. National Arboretum U.S. Department of Agriculture Author: World Trade Press