Challenges remain in reintroducing America...( WEST LAFAYETTE Ind. - Researchers ha...)

WEST LAFAYETTE, Ind. - Researchers have developed a breed of American chestnut that is resistant to the fungal blight that decimated its population in the early 1900s.

But the return of this "king of trees," so-called for its picturesque form and towering height of more than 100 feet, remains hampered by a slew of obstacles, said a Purdue University researcher.

"We are on the verge of overcoming chestnut blight, but there is a whole new set of obstacles to get past yet," said Douglass Jacobs, an associate professor of forestry and natural resources who is helping develop the blight-resistant chestnut.

To reintroduce the American chestnut, he said, researchers must get past several policy limitations, gather new data, educate the public about the species and address new threats posed by exotic pests. He details these and other challenges in a paper published in July's issue of the journal Biological Conservation.

Once a dominant forest species throughout much of the Eastern United States, ranging from Maine to Mississippi and concentrated in the Appalachian regions, the American chestnut was known for its annual largesse of nuts, rot-resistant wood and sheer size. An introduced Asian fungus nearly eliminated the tree.

A breeding program begun by the American Chestnut Foundation recently produced a blight-resistant hybrid tree that derives its resistance from the Asian chestnut and contains 94 percent of the American chestnut's genetic material, Jacobs said.

Nevertheless, the supply of blight-resistant trees remains low, and the tree isn't likely to be available to the public for about a decade. More resources need to be directed toward breeding programs, he said.

More existing trees also need to be included in breeding programs as soon as possible to produce a genetically diverse population, Jacobs said. Although few adult chestnuts remain throughout the tree's native territory, a significant num
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