For topping: Blend together flour, sugar, cinnamon, and butter in a small bowl with your fingertips until mixture resembles coarse meal. Add nuts. Set aside.
For bread: Put a rack in middle of oven and preheat oven to 350 degrees F. Butter two 9 X 5 inch loaf pans. Set aside.
Sift together flour, salt, baking soda, cinnamon, nutmeg or mace, cloves, ginger and allspice into a medium bowl.
Whisk together pumpkin oil, sugar, and eggs in a large bowl.
Add flour mixture, stirring until well combined.
Fold in apples.
Divide batter between buttered loaf pans. Sprinkle half of topping evenly over each loaf.
Bake until a wooden pick or skewer inserted in center of bread comes out clean, 50 to 60 minutes. Cool loaves in pans on a rack for 45 minutes, then turn out onto rack and cool completely, about 1 hour.
Yield: two loaves.