The Return of the American Chestnut Tree to the Eastern United States

In the early Twentieth Century the great (to 100 ft high) and beautiful American Chestnut tree was the dominant tree in the Eastern forests. 

In my hikes through the hardwood forests of the Eastern U.S.A. I have occasionally come across sprouts springs from rotted stumps.  What I was seeing were American Chestnut trees attempting to come back from the "great blight" which almost drove them to extinction.  The great blight began in Central Park in New York City in 1904 (the year before my mother's birth) and ravaged the species that in 1935 (the year of my birth) they were gone.  However, they persisted to the degree that some shoots would sprout and would bear fruit.   

David Evans Nov 24, 2011

The imposing 100-foot American chestnut tree that once dominated forests in the eastern U.S. may soon return, fortified by a new resistance to an Asian fungus. That blight essentially wiped out the tree during the past century, altering entire forest ecosystems. Scientists are releasing a sixth-generation hybrid this year for planting in several locations, confident that it will show the resistance of its hardy Chinese cousin.

The hybridization began decades ago, when breeders crossed the American and Chinese chestnuts to obtain the resistance genes. But because the American variety grows up to 50 feet taller and lacks lower branches, the researchers have had to backcross repeatedly to recapture those traits. The sixth generation should now have about 94 percent American character and “should have high resistance to the blight,” says Sara Fitzsimmons, a research technologist at Pennsylvania State University’s School of Forest Resources who works on the project. She won’t rest assured, however, until the trees grow on national forest­land for 10 years or so. Meanwhile scientists will continue to breed seedlings optimized for the sharply different local conditions from Maine to Georgia.

If the sixth generation shows the required resistance, Fitzsimmons foresees chestnut trees being available in garden centers in about 25 years. And with oaks in decline because of gypsy moth infestation, the reemergence of hardy chestnuts would provide prodigious quantities of nuts for animals and valuable biodiversity.

                                                          

(From Scientific American , March 2009)