David Elm - Ulmus davidiana v. mandshurica
Elm Family: Ulmaceae
Range: Europe / USDA Hardiness Zone: 3
This fast-growing tree is resistant to Dutch Elm Disease


 

 
23-year-old David Elm

Once a very popular and long-lived (300+ years) shade and street tree, American Elm suffered a dramatic decline in the 1950's with the infestation of Dutch elm disease, a fungus spread by a bark beetle. The wood of American Elm is very hard and was a valuable timber tree used for lumber, furniture and veneer. The Indians once made canoes out of American Elm trunks, and early settlers would steam the wood so it could be bent to make barrels and wheel hoops. It was also used for the rockers on rocking chairs.

Ulmus davidiana or David Elm is a deciduous tree widely distributed across China, Mongolia, Korea, Siberia and Japan, where it is found on wetlands along streams at elevations of between 2000 m and 2300 m. It grows to a maximum height of 15 m, with a slender trunk of no more than 0.3 m d.b.h. (diameter at breast height); the bark is longitudinally fissured. The leaves are obovate to obovate-elliptic < 10 cm x < 5 cm, with a rough upper surface. The wind-pollinated petal-less flowers are produced on second-year shoots in spring, followed by samarae that are obovate < 19 mm long by < 14 mm wide.

Evaluated with other Chinese elms at the Morton Arboretum, Illinois it was found to have a good resistance to Dutch elm disease, elm leaf beetle, and elm yellows. It was also considered to have a remarkable resemblance to the American Elm U. americana in all but ultimate size. -- adapted from Wikipedia

 


Bark

Flower: Monoecious; small, in drooping clusters of 3 to 5, appear in early spring before leaf buds open.
Fruit: Rounded, flat, pappery, wafer-like samaras, 3/8 to 1/2 inch across, deeply notched at apex, hairless except for margin; ripen in spring.
Twig: Slender, glabrous, slightly zigzag, reddish brown; buds ovate, over 1/4 inch long, reddish brown with darker edged scales, often placed a little to one side of the twig.
Bark: Dark, ashy gray, flat-topped ridges separated by diamond-shaped fissures; outer bark when sectioned shows distinct, titleernating, buff colored and reddish brown patches. When young it is often quite spongy.
Form: In the open, the trunk is usually divided into several large, ascending and arching limbs, ending in a maze of graceful drooping branchlets.
 

 
 

 

              
 
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