Abstract

All tillage moves soil laterally as well as vertically. With each tillage operation, soil preferentially moves downslope, and some soil usually leaves the tilled zone in the form of clods deposited along field borders. Over time, these clods, along with stones removed from the tilled area and sediment deposited by runoff, coalesce to form terraces or lynchets. The formation of such terraces may or may not be desirable but can hardly be avoided if field boundaries are fixed for long periods of time. This entry reviews research into terrace formation by tillage, identifies ways in which these terraces can be advantageous to soil and water conservation, and discusses problems that have been recognized with tillage terraces.