I always enjoy seeing my neighbor's tree on my daily walks, but especially when it is blooming. This photo was taken over a week ago and the blooms are now gone.
From my favorite tree guide, The Sibley Guide to Trees:
"The magnolias are an ancient lineage of trees and are considered "primitive" by botanists. Most other plants with showy flowers have large and colorful petals backed by smaller, leaf-like sepals. On magnolias, these two parts are not differentiated, and the flower is composed simply of some number of "tepals", intermediate between petals and sepals. Magnolia flowers are pollinated mostly by beetles, considered primitive, given the relatively recent evolution of bees."
Native magnolias are mostly a southern tree (except for the tulip tree). The ones in our neck of the woods are cultivated.