They were likely Black Locust blooms. They smell heavenly too.

Sue

Here is a link that might be useful: Black Locust blooms Google image search

Probably black locust. Did you get a whiff of the scent? Sweet, honey-like? (It's one of my favorites.) The leaves are multiple small leaflets on a stem, like a tree version of peas.

Now, the large shrubs now covered with white flowers along the roads are the hated japanese honeysuckle. This is the time of year when you can appreciate just how invasive this foreigner has been.