Perennial crops are crops that – unlike annual crops – don't need to be replanted each year. After harvest, they automatically grow back. Many fruit and nut crops are naturally perennial, however there is also a growing movement to create perennial alternatives to annual crops. For example, The Land Institute has bred a perennial wheat crop known as Kernza. By eliminating or greatly reducing the need for tillage, perennial cropping can reduce topsoil losses due to erosion, increase biological carbon sequestration, and greatly reduce waterway pollution through agricultural runoff due to less nitrogen input.