Have a magnolia. Not sure whether a shrub or a tree or even which variety, but its getting rather big. Its been in the garden for at least 20 years. seems to flower at least twice a year, early spring and sometimes late spring summer. Not sure if I can hard prune to turn it into a more tree like structure,with just one trunk rather than all the low branches. Its about 6 -8 feet spread at the lower branches and about 18 foot tall. Can you advise before it takes over.
It's unclear what type of Magnolia you have or your growing zone.
These links may help you.
You can also take a leaf sample to your County Extension Office for an id of the tree.