The Blodgett Tract is a 2,440-acre forest located in Columbia County about four miles south of the Columbia River in the upper Nehalem basin. The western boundary of the tract is the Clatsop County line, which is also the eastern boundary of the Clatsop State Forest. The other three sides of the tract are surrounded by private industrial forestlands. The upland conifer stands are predominantly Douglas-fir and western hemlock with a small amount of western redcedar and Sitka spruce. Riparian areas are dominated by red alder that in some areas is mixed with Douglas-fir, western redcedar and Sitka spruce. The Tract is underlain by marine sedimentary rock. The rock is composed of tuffaceous silts and sands that were derived from sand and volcanic debris from landmasses to the east, and were laid down when this area was shallow sea. There are intrusions of basalt in the sedimentary rock that were intruded when the rock was still submarine. These basalt intrusions show up in road cuts on an irregular basis. The sandstone is very incompetent and thus weathers easily. This is evidenced by an almost complete lack of bedrock outcrops on the forest, including the road cuts.