The common trees that cover Massachusetts are maple, birch, beech, oak, pine, hemlock, and larch. Common shrubs include rhodora, mountain laurel, and shadbush. Typical wildflowers include the Maryland meadow beauty and false loosestrife are typical wildflowers found in Massachusetts. Several varieties of orchid, lily, goldenrod, and aster are also found in this region. Northeastern bulrush, sandplain gerardia, and small whorled pogonia are listed as threatened in 2003.

As many as 76 species of mammals including 74 native species are found in Massachusetts. Common native mammals include the white-tailed deer, bobcat, river otter, striped skunk, mink, ermine, fisher, raccoon, black bear, gray fox, muskrat, porcupine, beaver, red and gray squirrels, snowshoe hare, little brown bat, and masked shrew. Among the Bay State's 336 resident bird species are the mallard, ruffed grouse, bobwhite quail, ring-necked pheasant, great horned and screech owls, downy woodpecker, mockingbird, cardinal, and song sparrow. Twenty-one Massachusetts animal species were classified as threatened or endangered in 2003. They included the American burying beetle, the bald eagle, puma, shortnose sturgeon, five species of whale, and four species of turtle.