Indian bean tree (Catalpa bignonioides), fam. Bignoniaceae.
Originates from southern USA, and maybe because of this it opens its buds and blooms much later than most other trees. This is not a songle unusual feature of catalpa; it also has peculiarly large leaves, with their whorly arrangement on the stems by three (while most plant has alternate or opposite leaves); and the longest fruits, remaining on the tree during the whole year, even after the fuzzy seeds have flown away from them. The seeds, besides, have high germination rate; and if you have not missed the moment of fruits opening and managed to collect them, you can plant a whole grove with the descendants of one tree.