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[六级大学英语阅读] 六级冲刺练习:阅读(133)

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  Logically, therefore, research to solve problems is a major job of the Forest Service. It covers the whole forestry field, including the protection and management of forests, related rangelands, and water-sheds; utilization of forest products; and the economic aspects of forestry. The Services regional forest and range experiment stations and its Forest Products Laboratory are constantly making new forestry studies throughout the United States and announcing new forestry facts.

  Redeeming the American Chestnut. Scientists have long been seeking ways of bringing back that valuable and storied tree, the American chestnut. Attacked by a blight brought in from Asia about 1900, practically all of our native chestnuts were killed. Their gaunt white skeletons are a reminder of a tree whose range extended from New England to Alabama and Louisiana. But there is a glimmer of hope. Forest Service scientists have found a few individual trees that seem to be resistant to the disease. Buds or branches from 28 of these tough survivors have been grafted to other root stocks for multiplication and the chance for further study of their resistance. Forest research may yet make the American chestnut once again tempt the palate , and also help supply the nations timber needs.

  Can Lightning Fires Be Prevented? Foresters have a hard job making people careful with fire in the forests. At the same time, some of them are trying to make Nature cut down the number of fires she starts with her most powerful fire-starting weapon, lightning.

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