AUGUSTA (AP) - When it comes to building homes, more and more people are apparently developing a taste for Henry David Thoreau's "tonic of wilderness," according to a survey by the Land Use Regulation Commission.

Population growth in Maine's unorganized territories is outpacing the rest of Maine, and the homes that are being built aren't just on the fringe of towns and cities but deep in the woods, according to the report created for LURC.

The commission is studying trends in the unorganized territories as it prepares a 10-year update of its comprehensive land use plan.

The "Patterns of Change" study found that the year-round population in the unorganized territories grew by about 5 percent between 1990 and 2000 - compared to 4 percent for the state - while the number of housing units grew by 16 percent.

More than half of the new homes built in unorganized territories from 1971 to 2005 were built far away from regional service centers, the report said. Of concern to the Natural Resources Council of Maine is that 72 percent of homes built during that period were constructed without any formal review process.

"I think what we are seeing is wilderness sprawl," said Cathy Johnson, director of the council's North Woods Project.

The movement of population away from areas with services such as police, fire and hospitals can be problematic, said Caroline Eliot, a LURC planner.

The commission's analysis found that 45 percent of new dwellings built between 1971 and 2005 are located in only 21 townships characterized as being near both a service center and high-value natural resources.

The rest of the homes built during that period were dispersed throughout the territories.

"You get to the point where you have to build redundant infrastructure ... and you are extending the service region," Eliot said. "That is not a particularly efficient model for the delivery of services."

Nonetheless, there's demand for homes in these wilderness outposts.

In northern Somerset County, a subdivision of lots greater than 40 acres was created in an area with no roads and no power on former timberland, said Eliot. More than 120 building permits have been issued for that subdivision, she said.

"It shows that there is a demand for wooded lots in the middle of nowhere," she said.