BENNINGTON, Vt. (AP) – A nonprofit organization will breed American Chestnut trees to be reintroduced to eastern forests.

The American Chestnut Foundation last week signed an agreement with the U.S. Department of Agriculture’s Forest Service. The deal allows the group access to land, personnel and resources.

The organization has found a way to breed blight-resistant chestnut trees and introduce them into the ecosystem by as soon as 2007, said Marshall T. Case, president of the American Chestnut Foundation.

The chestnut tree once comprised 25 percent of the tree coverage throughout much of the country, Case said. In the early 1900s billions of trees were killed by blight caused by fungus accidentally imported on Asian chestnut trees, he said.

By 1950 the species, which had occupied some nine million acres of eastern forests, had almost disappeared.

“The loss of these trees is considered by some measures to be among the greatest environmental disasters to befall the Western Hemisphere since the last ice age,” Case said.

The foundation, which was established in 1983, has developed a way to crossbreed the American with a blight-resistant Chinese chestnut.

The foundation has 11 chapters nationwide. All of the chapters will develop the trees in orchards and then work with the forest service to find an area to plant them where they can reproduce naturally.

The Department of Agriculture’s Forest Service manages 191 million acres of national forests and grasslands.