Wood pellets are a type of wood fuel, generally made from compacted sawdust or other wastes from sawmilling and other wood products manufacture,[1] but also sometimes from sources such as whole-tree removal or tree tops and branches leftover after logging and which otherwise help replenish soil nutrients.[citation needed] Pellets are manufactured in several types and grades as fuels for electric power plants, homes, and other applications in between.[2] Pellets are extremely dense and can be produced with a low moisture content (below 10%) that allows them to be burned with a very high combustion efficiency.[