Thousands of acres of open space in the area are protected by conservation easements held by land trusts. Thousands more are threatened. Hear how conservation organizations are protecting open space for the future, and how you can protect valued open spaces in Philadelphia watersheds. Presentations by Chestnut Hill Conservancy, Erdenheim Farm, Friends of the Wissahickon, Natural Lands Trust, Preservation Alliance for Greater Philadelphia, Whitemarsh Foundation, and Wissahickon Valley Watershed Association, followed by Q & A. Light refreshments. Free and open to the public but registration is requested.