The Collaborative International Dictionary of English v.0.48:

Fringe tree \Fringe tree\
   A small oleaceous tree (Chionanthus virginica), of the
   southern United States, having clusters of snow-white flowers
   with slender petals. It is often cultivated.
   [Webster 1913 Suppl.]

WordNet (r) 3.0 (2006):

fringe tree
    n 1: any of various small decorative flowering trees or shrubs
         of the genus Chionanthus