Peel the turnips and coarsely grate them into a bowl. Toss with salt and vinegar. Cover and set aside at room temperature for 1 hour.

Cut the rhubarb into 2-inch pieces. Cut each piece lengthwise into 3 strips. Wash in cold water and drain.

Place the rhubarb in a large saucepan and toss with the sugar. Cook the rhubarb over moderate heat for 5 minutes, or until the rhubarb begins to wilt but still is slightly crisp.

Drain the grated turnips in a colander or strainer, pressing out as much liquid as possible. Fold the turnips into the rhubarb and cook until heated through. Serve immediately.