Dan Mummert splashes through a rushing creek to grab a Hemlock tree branch, pulling it close and twisting it to see the underside.

"That's what I thought I'd find," he says sadly. "See here, these little white clusters, that's the Wooly Adelgid."The Woodly Adelgid is a pest that has been decimating the state's Hemlocks. Mummert could spot the affected tree at 100 yards."If a Hemlock tree is healthy, you shouldn't be able to see through it," he explains, pointing out a healthy Hemlock just 30 yards from the affected one. "Look at the difference between those two trees."Mummert is a wildlife diversity biologist for the Pennsylvania Game Commission, handling the Private Landowner Assistance program in the PGC's southeast region. He's one of six wildlife diversity biologists which work from the PGC's six regional offices.Hemlocks and other spruce and pines are important because they provide shelter and cover for a wide range of woodland denizens, including songbirds and small mammals. The trees are just one piece of the puzzle that contributes to a diversified habitat."People often have one or two species that they'd like to target, so it's those species they're considering when they make improvements to the habitat," Mummert said. "But often improvements to the habitat benefit many more species, wildlife and birds, because it's all part of the puzzle."Private Landowner Assistance ProgramAsked to guess how many bird and mammal species live in Pennsylvania, what would you say? 100? 250?Currently there are 467 bird and mammal species flying and roaming in the state, and 100 of those are considered "species of concern."The state's 45,000 square miles are 85 percent privately owned. Realizing that sustaining those species was dependent on the private landowners, in 2004 the PGC created the Private Landowner Assistance Program and hired six regional wildlife biologists.How PLAP WorksTo participate, the private landowner must have 10 acres. After making an initial phone or email contact with the regional biologist (this area is the Southeast Region, dmummert@state.pa.us, 610-926-3136), the biologist will send a short survey for the landowner to complete.The survey includes questions about the current conditions of the property, as well as goals that the landowner has. There is also a section for the landowner to check off any species that have been seen, such as Great Blue Heron, Barn Owl and numerous songbirds.Once the survey has been received, the landowner and biologist walk the property, observing habitat conditions and discussing any changes that could be accomplished. Goals of the PLAP program are to provide habitat that's important for the species of concern, as well as create more diversity of a habitat.The biologist will send the landowner a management recommendations report, and the landowner may contact the biologist with questions. There's no charge for the program, and there's no requirement that the landowner must allow public access.From 2004 to 2013, wildlife diversity biologists made 1,189 site visits with private landowners and enrolled 180,735 acres in the Private Landowner Assistance Program.