The diverse habitats of Gifford Pinchot State Park support a variety of wildlife through all seasons. The basis for the many habitats is diabase rock that underlies most of the park and was created when molten rock intruded the sandstone and melted it into a new kind of rock. Many of the diabase rocks have unique cracks that formed as the rocks slowly cooled. Winter is the best time to see the plentiful boulders and rock outcroppings because the trees have no leaves and the undergrowth in gone. Winter is also a good time to see woodpeckers and evidence of their presence. Gifford Pinchot has at least six species of woodpeckers. Spring and fall is the time of bird migrations. Gifford Pinchot State Park is an area of forest surrounded by many farm fields and is a rest stop for many migrating forest birds. Warblers, vireos and thrushes stop to rest and eat before flying on to their breeding or winter homes. Pinchot Lake and its shoreline wetlands are a beacon that lures waterfowl by the thousands. Mergansers, Canada geese, mallards, loons, teal and many other ducks can be seen swimming, diving and dabbling for vegetation and small fish.

Spring is the time for wildflowers. Fields and forests get a carpet of bluebells and marsh marigolds and many other flowers. Before it gets it leaves, the tree redbud bursts into pink to lavender flowers. In Pinchot Lake, male largemouth bass make nests and aggressively defend their territory and fry (baby fish).

Summer is the time of lush green vegetation and growing young animals. By fields, watch for spotted fawns and frantic bluebirds searching for food to feed their hungry chicks. Butterflies reach their peak numbers and can be seen floating from flower to flower in the fields and wetlands.

In the fall, the deciduous trees lose their chlorophyll and their leaves reveal beautiful reds, oranges and yellows. While the other trees lose their leaves, the eastern red cedar keeps its green needles throughout the year. Look for this oval-shaped tree growing in old fields. Many of the old farm fields are "reverting" to forest and red cedar is usually the first tree to grow in the fields and will improve the soil for other trees.

Straight Hill Area: Located east of the campground, the Straight Hill Area is an interesting place to study nature. All stages of forest succession are shown. Abandoned farm fields are being replaced by eastern red cedar, and the cedar stands are being replaced by deciduous forests dominated by red and white oaks. The area also features some mature oak stands along the hillsides. A special brochure on the geology of the park describes the large diabase boulders found in the area. This brochure is available at the park and campground offices, and the interpretive center.