In a large saucepan cook celery, carrots, onion, thyme, sage, and pepper in hot oil over medium heat for 4 minutes. Stir in broth or soup stock, water, and potatoes; add turkey leg. Bring to boiling; reduce heat. Simmer, covered, about 5 minutes.
Stir in zucchini and corn. Return to boiling; reduce heat. Simmer, covered, about 5 minutes or until potatoes are tender.
Remove from heat. Remove turkey leg from saucepan; let stand until cool enough to handle. Remove meat from turkey leg; discard turkey bone and skin. Coarsely chop meat and return to saucepan. Heat through.