Enviros are becoming increasingly concerned about the development of “inholdings,” or private land within national parks and national forests. There are about 50 million acres of such land, only a fraction of the total land within park and forest boundaries, and in the past most landowners have kept their areas in a natural state or sold them to the feds for preservation. But increasingly, prices for some inholdings are soaring above what the government or conservation groups can afford to pay, so private investors and developers are moving in. The National Park Trust estimates that 20 percent of the privately held land within national parks and forests is “in imminent danger” of development. The National Park Service has a list of more than 10,000 privately owned tracts that it would like to buy, at a cost estimated at $1.35 billion, but Congress has not allocated nearly enough money for such purchases.

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