Theodore Roosevelt set aside large parts of land to be conserved for future generations rather than be sold or developed. These lands eventually became major national parks and forests, containing wildlife and acres of forests and water. The idea was to ensure the sustainability of natural resources, and what's exactly what happened.

The problem is, everything is growing. Not just the trees or grass, but human communities, too. These communities are brushing up against the federally protected areas, and pollution is beginning to seep in. In addition, there's not much space left for all of the wildlife to stay. Maintaining healthy forests requires cooperation with neighbors, which may or may not always happen, and making sure clean water will