Conservation tillage methods, including no-till, strip-till, and vertical-till, aim to protect soil and water quality by reducing erosion and runoff. These methods may also increase moisture levels, increase soil organic matter content, and improve the overall soil habitat by reducing soil disturbance. However, there is no “best” choice for conservation tillage systems. Different methods work differently depending on the operation.
No-till means that little or no tillage occurs, keeping the maximum amount of residue on the surface of the land. Although the land stays cooler longer due to this layer of residue, the residue left on the surface in this system provides protection against soil erosion and runoff, particularly on sloped land and other terrain that is especially susceptible to runoff. The cooler temperatures may result in the producer planting seeds later in the spring than under a different system. No-till reduces or eliminates the need for some machinery use, time, and effort that would have been devoted to tilling; however, since some of the goals of traditional tillage practices include weed and pest control, producers will likely have to look into other practices to control unwanted organisms on their fields.
Strip-till involves tilling narrow strips of land so that there are residue-free strips in between strips of residue on the land. By only disturbing strips of soil, the producer is able to benefit from leaving residue on the surface while reducing the risk of the potential weeds and pests. Compared to conventional-till, strip-till practices often have less intensive machinery and energy requirements. The tilled strips allow for the soil to warm and moisture to evaporate sooner, and seeds are generally planted in them. This practice combines some of the benefits of tillage with the conservation benefits of no-till practices.
Vertical-till allows farmers to use minimal soil disturbance to manage residue without removing all residue from the soil surface. It involves machinery that quickly works to level out the soil surface and cut down on soil residue. Like strip-till practices, this allows for more moisture evaporation and soil warming than no-till practices. Vertical-till may be favorable for some cropping systems, such as multiple years of corn rotations, which leave high amounts of residue; it is an option for reducing the amount of residue and encouraging residue decomposition. Since manure application also stimulates this decomposition, this may be a good practice for operations with lower levels of manure application.
Many producers claim that these practices have improved their yields in addition to conserving soil and protecting water quality. It is important to identify the characteristics which may make one of these systems better suited for your operation. Finding the best system may involve learning about systems used by other producers and how they incorporated these systems into their practices. New developments in technology and an improved understanding of soil ecosystems allow for flexibility in conservation practices to fit the goals of individual operations.
http://www.mda.state.mn.us/protecting/conservation/practices/constillage.aspx
http://extension.psu.edu/plants/crops/soil-management/no-till/vertical-tillage-yes-or-no
http://efotg.sc.egov.usda.gov/references/public/WI/329.pdf
http://www.nrcs.usda.gov/wps/portal/nrcs/detail/ia/newsroom/features/?cid=nrcs142p2_008163
http://www.nrcs.usda.gov/wps/portal/nrcs/detail/ia/newsroom/features/?cid=stelprdb1077078