I just moved into a new house where there are two old looking grape vines that were once climbing along an old fence. The fence has fallen down and the vines are tangled and broken. They are along the edge of a gravel driveway, facing south-east but are mostly shaded by large conifers. Should they be pruned or cut down close to the ground? Should I mulch around their bases? Considering their location, is it worth trying to bring them back or should I remove them to a more sunny location?