American elm
Quick Summary
The American elm (Ulmus americana) is a large tree native to eastern and central North America, characterized by its gradually spreading branches and pendulous branchlets. Elms, in general, are forest and ornamental shade trees known for their height and attractive foliage. Their leaves are often lopsided at the base, and their flowers appear before the leaves, borne in clusters. The fruit is a samara, a nutlike seed surrounded by a winglike structure.12
Unfortunately, many elm species, including the American elm, are highly susceptible to Dutch elm disease, a devastating fungal disease spread by bark beetles. This disease has significantly reduced elm populations across Europe and North America.32
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Dutch elm disease…regions wherever the very susceptible American elm (Ulmus americana) grows. In the late 1940s, another virulent species, O. novo-ulmi, was described in Europe and the United States, and heavy elm losses continued. This species was introduced to Auckland, New Zealand, in 1989, where it was nearly eradicated with aggressive control…
Read More…regions wherever the very susceptible American elm (Ulmus americana) grows. In the late 1940s, another virulent species, O. novo-ulmi, was described in Europe and the United States, and heavy elm losses continued. This species was introduced to Auckland, New Zealand, in 1989, where it was nearly eradicated with aggressive control…
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plantDispersal and colonizationThe American elm (Ulmus americana), a magnificent tree of the moist forests of lowlands throughout eastern North America, has suffered a similar but less-comprehensive loss through the ravages of another exotic fungus, Dutch elm disease (Ceratocystis ulmi), which was imported from Europe on infected wood probably…
Read MoreThe American elm (Ulmus americana), a magnificent tree of the moist forests of lowlands throughout eastern North America, has suffered a similar but less-comprehensive loss through the ravages of another exotic fungus, Dutch elm disease (Ceratocystis ulmi), which was imported from Europe on infected wood probably…
Read More