Preheat oven to 375 degrees F. From orange, grate peel and divide between 2 large bowls; squeeze 1/4 cup orange juice into small bowl.
In 1 large bowl with peel, combine strawberries, rhubarb, and granulated sugar until well mixed. Into small bowl with juice, add cornstarch; stir until well mixed. Stir juice mixture into fruit mixture until well combined. Pour into 9-inch glass or ceramic pie plate; spread filling in even layer.
In other large bowl with peel, combine oats, brown sugar, flour, and pinch salt. With pastry blender or with fingertips, blend in butter until mixture forms coarse crumbs with a few pea-size pieces remaining.
Sprinkle oat mixture evenly over strawberry mixture. Place pie plate on foil-lined cookie sheet to catch any drips. Bake 45 minutes or until topping is golden brown and fruit filling is hot and bubbling.
Cool pie on wire rack until filling is set but still slightly warm, at least 1 hour. Serve warm.
Bake
2013