The northern hardwood forest is a general type of North American forest ecosystem found over much of southeastern and south central Canada, extending south into the United States in northern New England, New York, and Pennsylvania, and west along the Great Lakes to Minnesota and western Ontario. Some ecologists consider it a transitional forest because it contains species common to both the oak-hickory forest community to the south and the Boreal forest community to the north. The trees and shrub species of the Northern Hardwood Forest are known for their brilliant fall colors, making the regions that contain this forest type popular fall foliage tourist destinations.