1. Combine flour and salt in bowl. Cut in shortening with pastry blender until mixture resembles coarse meal. Sprinkle cold water, 1 tablespoon at a time, over mixture, tossing lightly with fork until pastry just holds together. Divide in half; shape each half into a disk. Wrap in plastic wrap. Chill 1 hour.Prepare Filling:
2. Combine strawberries, rhubarb, sugar, tapioca, ginger, cinnamon and salt in large bowl. Let stand 20 minutes.
3. Heat oven to 375 degrees F.
4. Roll out half of pastry on well-floured surface to 11-inch circle. Transfer to 9-inch pie pan. Trim pastry even with edge of pan. Spoon filling into piecrust. Dot with butter.
5. Roll out remaining pastry to 11-inch circle. Place over filling. Make decorative edge. Cut vents in top. Place on foil-lined baking sheet.
6. Bake in 375 degree F oven 1 hour, until golden. Tent with foil if browning too quickly. Remove to rack to cool. Makes 10 servings.