Special Sunday Roast Chicken

Name: Special Sunday Roast Chicken
Ingredients: 1 12-ounce unpeeled russet potato, well scrubbed, cut into 1-inch cubes; 1 12-ounce yam (red-skinned sweet potato), peeled, cut into 1 1/2-inch cubes; 2 large carrots, peeled, halved lengthwise, cut crosswise into 1 1/2-inch pieces; 3 medium parsnips, peeled, cut into 1 1/2-inch pieces; 1 1/2 tablespoons extra-virgin olive oil; 3 tablespoons unsalted butter, room temperature; 2 tablespoons finely chopped fresh sage; 1 garlic clove, pressed; 1 4-pound organic chicken; 1 teaspoon coarse kosher salt; 8 cups coarsely torn red or green mustard greens; 1 shallot, minced; 1/2 cup dry white wine; 1/4 cup water