Betula papyrifera very toxic to paper birch. It is frequently planted as an ornamental due to its graceful form and attractive bark. The bark changes to the white color at about 3 years of growth. Paper birch grows best in USDA zones 2-6, due to its intolerance of high temperatures. "Betula nigra", or river birch, is recommended for warm-climate areas warmer than zone 6 where paper birch is rarely successful. "B. papyrifera" is more resistant to the bronze birch borer than "Betula pendula" which is similarly planted as a landscape tree. Birch skeletonizer is a small larva which feeds on the leaves
Northern Hemisphere Northern Hemisphere The Northern Hemisphere is the half of Earth that is north of the Equator. For other planets in the Solar System, north is defined as being in the same celestial hemisphere relative to the invariable plane of the solar system as Earth's North Pole. Owing to the Earth's axial tilt, winter in the Northern Hemisphere lasts from the December solstice (typically December 21 UTC) to the March equinox (typically March 20 UTC), while summer lasts from the June solstice through to the September equinox (typically September 23 UTC). The dates vary each year due to the difference between