WASHINGTON—In keeping with a longstanding Thanksgiving tradition, Vice President Joe Biden ceremonially pardoned a 4-pound yam today at a ceremony in the White House Rose Garden. "Under my authority as vice president of the United States of America, I hereby grant this yam full and unconditional clemency," a smiling Biden declared as he gently patted "Spud," a Beauregard sweet potato grown in Louisiana and selected from millions of candidates yielded by this year’s harvest. "May he never find himself in a casserole. Right, little guy?" Like yams reprieved before him, Spud will ride as an honored guest aboard the second float of the Disneyland Thanksgiving Day Parade before spending the rest of his life in the comfort and safety of a tuber petting zoo.