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American Chestnut Blight 



Tlie American chestnut was once the most important hardwood species in the east- 

 ern U.S. The species was found in vast stands from Maine to Georgia before the turn 

 of the twentieth century, accounting for one-<juarter of all the standing limber in 

 eastern forests (USDA Forest Service 1991b). In 1904, an introduced fungal disease, 

 Cryphoneclna (= Endolhia) parastUca, changed the species composition of eastern 

 North .American forests. The disease was first observed on dying American chestnut 

 trees in the Bronx Zoological Gardens. Introduced to North America in a shipment 

 of Asian chestnut nursery slock, chestnut blight spread throughout eastern hardwood 

 forests at a rate of 24 miles per year (National Academy of Sciences 1975). By the 

 1950s, virtually all mature .American chestnuts had succumbed to the disease. 

 Ajncrican chesmut is now a minor understory component, existing as sprouts from 

 old stumps and root s)-siems (</. Burnham etat. 1986). 



Tlie species proxided timber, food, and tannin that were important to early European 

 settlers. In recent years, the emphasis on utilization of American chestnut for wood 

 products has overshadowed the importance of the species in wildlife food chains 

 (Schlarbaum 1989). Annually, the tree would produce large crops of hard mast, 

 unlike the oaks, hickories, and other trees that have replaced the chesmuL It is not 

 known exactly how critical American chestnut was to wildlife populations. American 

 wildlife biology was not well developed as a science in the late 1800s and early 1900s. 

 No surveys were conducted before or during the demise of the chesmut that could 

 document the impact on animal species (Pclton, personal communication). In addi- 

 tion, simultaneous widespread timber harvesting in eastern forests complicates 

 efforts to aisess the importance of chesmut to wildlife. Howes'er, historical accounts 

 and old photographs clearly indicate that wildlife was much more abundant before 

 the blight decimated the species. 



Different approaches have been used in attempts to develop a blight-resistant 

 American chesmut for eastern forests. These approaches include breeding within the 

 species, hybridization with blight-resistant .^sian hybrids and use of hypovirulent 



