Planting trees is not necessary in Massachusetts. Our tree species naturally seed in and are sustained by ample annual rainfall. Therefore, the vast majority of the forests in Massachusetts are made up of native species. However, there are specific instances where plantations of non-native species, such as red pine and Norway spruce, were established, particularly on town watersheds and state forests as a part of the Civilian Conservation Corp efforts in the 1930s. Since non-native species are by definition out of their native range, they are typically less vigorous and more susceptible to insects and disease. Converting your forest to native tree species that are well adapted to the site will increase your forest's resilience in a changing climate.