The wet season started and so fire related projects are harder to do. So I planted this years crop of yams using a different technique. The stones covering the mounds protect the yams from predators such as bush turkeys and pigs. The birds are to weak to lift the stones and pigs don't see the piles of stones as food. In time the yam vines will completely cover the structure. Then they will produce smaller yams on the vine and larger yams under the ground.