Forest Diseases
Authored By: D. J. Moorhead, G. K. Douce
Many diseases occur in the Appalchian forests. Most forest diseases are native and a natural part of the ecosystem. Diseases can help to keep the forest healthy be removing weak or injured trees. they also can improve wildlife habitat by creating holes in trees and snags. However some exotic diseases have been devastating to the ecosystem. These diseases are notnativeto the ecosystem and thus can spread unchecked, killing many trees and threatening the health of Appalachian forests. The biology, symptoms, spread, and management of these important diseases are outlined here.
| Chestnut blight | - This disease decimated the once abundant native chestnut (Castanea dentata) populations in the first part of the 1900s.
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| Dogwood anthracnose | - This disease is currently killing the majority of dogwoods (Cornus spp.) that occur at high elevations in the southern Appalachians.
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Dutch elm disease
| - Introduced in the 1930s,this disease has affected mostly urban populations of American elm (Ulmus americana), but American elm is slowly declining in forest stands as well.
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| Beechbark disease | - This disease has been in North America since the 1890s but didnt reach the southern Appalachians until the 1980s. The disease is caused by a combination of a beech scale insect and a fungus.
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| Oak decline | - This is a slow-acting disease complex with interactions between biotic and abiotic factors that combine to stress oaks (Quercus spp.). It has existed in eastern oak forests since the mid 1800s. Oak decline leads to gradual crown dieback and eventual mortality.
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| Butternut canker | - Butternut (Juglans cinerea) populations have continued to decline since this disease was discovered in 1967. An estimated 77% of the trees of this rare species have already been killed by butternut canker.
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| Sudden oak death | - This disease has recently been introduced into the eastern United States. Oaks (Quercus spp.) are most at risk but the host list continues to grow. The impact of this disease is going to have on the southern Appalachians is unknown but it has the potential to severely alter the biodiversity and decimate the populations of oaks, one of the most abundant group of trees in the eastern United States.
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Subsections found in Forest Diseases