Betula papyrifera resistant to the borer but when grown in subideal conditions the defense mechanisms of the tree may not function properly. Chemical controls exist. It is the provincial tree of Saskatchewan and the state tree of New Hampshire. People sometimes vandalize the bark of this tree by carving into it with a knife or by peeling off layers of the bark. Both forms of vandalism can cause unsightly scars on the tree. Betula papyrifera Betula papyrifera (paper birch, also known as white birch and canoe birch) is a short-lived species of birch native to northern North America. Paper birch is named
Alnus incana Alnus incana Alnus incana, the grey alder or speckled alder, is a species of alder with a wide range across the cooler parts of the Northern Hemisphere. It is a small- to medium-sized tree tall with smooth grey bark even in old age, its life span being a maximum of 60 to 100 years. The leaves are matte green, ovoid, long and broad. The flowers are catkins, appearing early in spring before the leaves emerge, the male catkins pendulous and long, the female catkins long and one cm broad when mature in late autumn. The seeds are small, long, and