Place the berries, lemon juice, orange zest, and lemon zest, in a large bowl. In a separate bowl stir together the sucanat and arrowroot, then add to the berries and toss gently to combine. Pour berry mixture into an 8 x 8 inch baking dish.
To make topping:
Mix flour, oats, sucanat, allspice, and salt together in a bowl. Add melted butter and maple syrup, stir to combine. Add the nuts and stir again. Sprinkle topping over the fruit.
Bake at 375 degrees F for 30 to 35 minutes. Let the crisp cool slightly before serving to allow the juices to thicken.