Heat oven to 350°, Spray cookie sheet with nonstick cooking spray or line with parchment paper.
Combine sugar, yolk, cinnamon, nutmeg, ginger and pumpkin in a bowl and mix well. Stir in pecans. Unroll crescent dough onto cookie sheet. Firmly press perforations to seal, pressing to form a 7x13-inch rectangle. Spoon filling down the center of the dough, forming a 3 1/2-inch wide strip, leaving 1-inch at top and bottom.
With kitchen scissors or sharp knife or pizza cutter, make cuts 1-inch apart on long sides of the dough rectangle, just to edge of filling. Fold strips at an angle across filling, overlapping ends and alternating from side to side.
Beat egg white in small bowl until frothy and brush over the dough. Sprinkle with cinnamon sugar.
Bake for 20 to 30 minutes or until dark golden brown.
Sprinkle immediately with powdered sugar or make a glaze and drizzle over.
Combine 1/2 cup powdered sugar and 1 tablespoon milk in a measuring cup and whisk until smooth. Drizzle over warm braid. Sprinkle with additional chopped pecans, if desired. Serve warm.