The exotic flowers of Albizia julibrissin f. rosea (silk tree) appear late in the season. This broad-crowned, medium-sized deciduous tree has bipinnate leaves. It needs a well-drained soil in full sun. In Japan and some areas of the United States it has become an invasive species.
When I read your questions it was almost dark. I grabbed my camera and ran up the road a little. Apparently it does fold down the leaves and go to sleep. I did not know this. I’ve always heard it called mimosa, but I believe that it is Albizia julibrissin.