The United Nations' Care for Palestine Refugees

The sand dunes of the Gaza Strip presented a barren prospect to UNRWA in its efforts to provide employment for the refugees there, 70% of whom were farmers. An answer was found, however, in the mimosa tree, a quick growing, bushy tree which, in as little as three years, can stabilize shifting sands by covering them with waving green thickets; almost immediately grasses and other low vegetation will begin to sprout.
Refugees planting seedlings on a sand dune near Gaza. May 1957.