Hi ZZ,
In addition to what has been said I'd like to add that these plants are often neglected for long periods of time, not getting water when needed, left out in direct sun for long periods of time and often very rootbound.
I would also like to comment on the trees that you have noted and I'm including some links for you to read.
Honey locust - Gleditsia triacanthos - Several different varieties but will develop LARGE surface roots over time (up to 35' from the trunk) and lift sidewalks and driveways.
http://hort.ifas.ufl.edu/trees/GLETRIA.pdf
Pear blossom tree is not a name I'm familiar with, but pear trees are known for having weak limbs that break in storms and are not considered a good purchase.
Pyrus calleryana - 'Artistocrat', 'Callery' and 'Redspire'.
http://hort.ifas.ufl.edu/trees/PYRCALA.pdf
http://hort.ifas.ufl.edu/trees/PYRCALB.pdf
http://hort.ifas.ufl.edu/trees/PYRCALC.pdf
If you are looking for trees for specific locations or attributes, let us know so we can help you. We will need to know where you live.
If you want to research trees that you see while out shopping or any recommended, this site has loads of info such as tree litter, invasive roots, weak limbs, etc.
http://hort.ifas.ufl.edu/trees/index.htm
Hope this helped,
Newt
When weeding, the best way to make sure you are removing a weed and not a valuable plant is to pull on it. If it comes out of the ground easily, it is a valuable plant.