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Identification Clues:
This deciduous tree has alternate branching,
large, doubly serrate leaves, and gray-brown furrowed bark on the trunk.
Run you fingers hback and forth over the leaves to feel their roughness.
Of the elms, the American species has the largest leaves, ranging from
2 to 6 inches long. The small flowers appear early in the spring,
with the single-seeded samara fruits occurring by May.
Distribution:
The American Elm is native to the Eastern
U.S. and the Great Plains. It has been widely planted along city
streets as a shade tree because of its umbrella-like canopy.
Highlights:
American Elms in the U.S. have been decimated
by Dutch Elm Disease. This fungus can be transmitted from tree to
tree by bark Beetles or directly through root grafting. There is
no cure; and because elms are so often planted in lines, once one tree
is affected, its neighbors soon succumb. The disease has been in
the U.S. since 1930, but it was not documented in South Dakota until 1967.
This disease has begun to kill trees in Aberdeen and on the NSU campus.
Once infected, an elm tree could die within four weeks. Elms are
valued for timber and as food for wildlife. Rabbits and deer browse
on elm twigs; grouse, prairie chickens and squirrels eat the seeds. |
