Places apples in a 11 x 7 inch baking dish. Drizzle juice from lemon over apples.
In medium bowl, mix together brown sugar, oats, flour, salt and apple pie spice. With pastry blender, cut in butter until crumbly. Sprinkle over apples, press down lightly.
Bake, uncovered at 400º for 40 to 45 minutes or until apples are tender and topping is golden brown.