Heat oven to 350° F.
In a pot, over medium-high heat, bring the broth and 2 cups water to a boil. Add the wild rice and brown rice, reduce heat to low, and cover. Simmer until tender, about 45 minutes.
Melt the butter in a large skillet over medium-low heat. Add the onion and celery and cook for 10 minutes. Add the cooked rice, parsley, sage, pecans, apricots or cranberries, salt, and pepper and toss. Transfer to a buttered casserole. Cover and bake for 25 minutes.
In Advance: Assemble the dressing but do not bake it. Cover and refrigerate for up to 24 hours. Bake as directed, adding 10 minutes to the baking time.