They are EVERYWHERE here in Nashville, TN. I have four in my yard. They grow three to four feet a year! This tree is four years old and is close to 15-20 feet tall. It had blooms for the first time last year. We didn't plant ANY of our Mimosas; they just sprout from seeds
the birds drop. LITERALLY every house in the neighborhood has AT LEAST One Mimosa in the yard, and I have four.
The other omnipresent trees around Nashville are Crepe Myrtles, Bradford Pears, and Redbuds. I have at least one of each of those in my yard, too.