Black Locust, Robinia pseudoacacia
Bright white (see photos below) dangling flower clusters, brightness fades over time. The dangling characteristic is evident when the wind blows. See photo below for leaves. Locusts have an very upright, open silhouette (as opposed to conical, round, or rectangular).
Blooms last half of May (up until Memorial Day) in my area and produce an abundant, early nectar.
Leaves are not nearly as even in size and shape and much bigger than the more cultivated types (typical in parking lots).
In autumn, the seed pods are difficult to see because they are short (see photo), less than the span of my palm. Leaves turn yellow by early Oct.