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
Crataegus Crataegus Crataegus (), commonly called hawthorn, quickthorn, thornapple, May-tree, whitethorn, or hawberry, is a large genus of shrubs and trees in the family Rosaceae, native to temperate regions of the Northern Hemisphere in Europe, Asia and North America. The name "hawthorn" was originally applied to the species native to northern Europe, especially the common hawthorn "C. monogyna", and the unmodified name is often so used in Britain and Ireland. The name is now also applied to the entire genus and to the related Asian genus "Rhaphiolepis". The Latin name "Crataegus" is from the Greek "kratos" "strength" and "akis" "sharp", referring