Question
Hi Marc
There is a Bradford Pear tree planted 5 meters from our home. It is 11 years old and about 30feet tall. Is it wise to leave the tree there or can it potentially cause subsidence or other damage to our building?

Answer
It will be fine.  5 meters is very generous spacing, and the Bradford doesn't have invasive root problems, even when horticulturally grafted to a different pear root stock (i.e., not a Bradford variety of base plant).  

Pears have shallow roots that tend to "sucker", but won't do damage to sidewalks and foundations like some other types of trees.

It is, however, a short-lived tree, and will only live an average of about 45-50 years or so.

~Marc