Grow and Maintain a Healthy Birch Tree
In many landscapes, birch trees begin to decline within a few years, and many trees die well before reaching maturity. A healthy birch tree should be able to survive and thrive for 40-50 years. In many yards, however, it is not unusual for birch trees, especially the white-barked birches, to die well before reaching 20 years of age.
The link address is: http://www.na.fs.fed.us/spfo/pubs/howtos/ht_birch/ht_birch.htm