At more than a dozen sites in Western Pennsylvania, volunteers are pitching in. At local, state and federal sites throughout the country, more than 170,000 people are expected to help maintain public lands by participating in the Sept. 25 National Public Lands Day, an initiative of the National Environmental Education Foundation.

With a rapid recent increase in the number of No Trespassing signs going up on private property across the country, public lands are growing more valuable to those who routinely go outdoors.

"For 2010, we have a special focus on recreation, volunteerism and how those who use public lands for sport can play a large part in protecting habitat and improving the quality of public lands for everyone," said Robb Hampton, director of National Public Lands Day, in a written statement.

Sponsored by Toyota. this year's cleanup effort targets some 2,300 sites. Organizers are reaching out to hunters and anglers, who are among the first to notice the closing of private lands and abuses of public property.

Among the Western Pennsylvania sites:

Allegheny River Various locations, 814-728-6163. Conemaugh River Lake Trail maintenance, construct boxes, plant trees, 724-459-7240. Jennings Environmental Education Center Trail improvement, water diversion devices, 724-794-6011. Laurel Hill State Park Hiking and bike trail maintenance, 814-352-8649. Loyalhanna Lake Trail maintenance, tree planting, habitat improvements, 724-639-9013. North Irwin Park Paint benches, general maintenance, 724-309-9363. Pleasant Valley Park Improve, extend park trail system and remove debris, 724-575-0116. Youghiogheny River Lake Shoreline clean-up, 814-395-3242.

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