“Tillage” can also mean the land that is tilled. The word “cultivation “has several senses that overlap substantially with those of “tillage”. In a general context, both can refer to agriculture. Within agriculture, both can refer to any kind of soil agitation. Additionally, “cultivation” or “cultivating” may refer to an even narrower sense of shallow, selective secondary tillage of row crop fields that kills weeds while sparing the crop plants. Tillage is a mechanical modification of soil structure require considerable expense of high-energy inputs to prepare the seed bed, to incorporate fertilizer, manure and residues into the soil, to alleviate compaction and to control weeds excessive tillage practices without residue retention may adversely affect long-term soil; productivity due to erosion and loss of organic carbon.