Strip-till is a conservation system that uses a minimum tillage

Tillage

Tillage is the agricultural preparation of the soil by mechanical agitation of various types, such as digging, stirring, and overturning. Examples of human-powered tilling methods using hand tools include shovelling, picking, mattock work, hoeing, and raking...

. It combines the soil drying and warming benefits of conventional tillage with the soil-protecting advantages of no-till by disturbing only the portion of the soil that is to contain the seed row. This type of tillage is performed with special equipment and can require the farmer to make multiple trips, depending on the strip-till implement used, and field conditions. Each row that has been strip-tilled is usually about eight to ten inches wide. Another benefit of strip-tilling is that the farmer can apply chemicals and fertilizer

Fertilizer

Fertilizer is any organic or inorganic material of natural or synthetic origin that is added to a soil to supply one or more plant nutrients essential to the growth of plants. A recent assessment found that about 40 to 60% of crop yields are attributable to commercial fertilizer use...

 at the same time as tillage.

Challenges of both Strip-till and No-till systems

In reduced tillage strategies, weed suppression can be difficult. In place of cultivation, a farmer can rely on cover crop suppression, mowing, crimping, or herbicide application. The purchase of mowing and crimping implements may represent an unjust expenditure. Additionally, finding an appropriate cover crop mix for adequate weed suppression may be difficult. Also, without mowing or crimping implements it may not be possible to achieve a kill on the cover crop. If mowing, crimping, and suppression with a cover crop mixture fail, herbicides can be applied. However, this may represent an increase in total farm expenses due to herbicides being used in place of cultivation for weed suppression.

There are some disadvantages specific to strip-till systems. Some farmers may not be able to strip-till if there is an early freeze. In grain or cereal crops there is a small margin of error because the farmer has rows only eight to ten inches wide. This can easily be countered with auto steering systems. Lastly, for some strip-till systems a large amount of horsepower

Horsepower

Horsepower is the name of several units of measurement of power. The most common definitions equal between 735.5 and 750 watts.Horsepower was originally defined to compare the output of steam engines with the power of draft horses in continuous operation. The unit was widely adopted to measure the...

 is required to pull the strip-till implement across the field. In a flat region a smaller tractor

Tractor

A tractor is a vehicle specifically designed to deliver a high tractive effort at slow speeds, for the purposes of hauling a trailer or machinery used in agriculture or construction...

 can pull a larger applicator with little trouble. However, in regions with gentle to steep slopes, the tractor may not have enough horsepower. This can be problematic because some farmers may not own a tractor large enough to pull "shank-type" strip-till implements. Additionally, purchasing a new tractor may be too costly.

Differences in the equipment used

No-till planters have a disk opener (commonly referred to as a no-till coulter) that is located in front of the planting unit. This coulter is designed to cut through crop residue and into the hard crust of the soil. After the coulter has broken through the residue and crust, the disk opener of the planting unit slices the soil and the seed is dropped into the furrow that has been created and then a press wheel closes the furrow. The pictures are of no-till drills and they use the same principles as discussed above to plant the season’s crops.

With strip-tillage systems more precision is needed. The farmer will work the ground with a specialized implement to till up an eight to ten inch row and at the same time incorporate the fertilizer or chemical that the farmer so chooses. If the applicator’s chemical or fertilizer meter is off slightly, the farmer will not be applying an accurate rate of the chemical. This could result in increased expenses or reduction of the efficacy of the fertilizer program.

Effects on the soils properties

When oxygen is introduced into the soil via tillage, the decomposition of organic matter

Organic matter

Organic matter is matter that has come from a once-living organism; is capable of decay, or the product of decay; or is composed of organic compounds...

 is accelerated. carbon

Carbon

Carbon is the chemical element with symbol C and atomic number 6. As a member of group 14 on the periodic table, it is nonmetallic and tetravalent—making four electrons available to form covalent chemical bonds...

, nitrogen

Nitrogen

Nitrogen is a chemical element that has the symbol N, atomic number of 7 and atomic mass 14.00674 u. Elemental nitrogen is a colorless, odorless, tasteless, and mostly inert diatomic gas at standard conditions, constituting 78.08% by volume of Earth's atmosphere...

, and phosphorus

Phosphorus

Phosphorus is the chemical element that has the symbol P and atomic number 15. A multivalent nonmetal of the nitrogen group, phosphorus as a mineral is almost always present in its maximally oxidized state, as inorganic phosphate rocks...

 were all higher in the no-till system than on reduced till, and conventional till systems in an Australian study (Thomas et al., 2007).

Strip tillage has some similarities with no-till systems because the surface is protected with residue. However, strip-till also has a similar effect on soil properties as conventional tillage systems because the farmer still breaks the soil’s crust which allows aerobic conditions to speed the decay of organic matter. A two-year study found that strip-till did not affect the amount of soil organic carbon or its extractable phosphorus (Kingrey et al., 1996).

Impacts on productivity

In one study, yields were higher in the strip-tilled area than in the area where no-till was practiced. In a low phosphorus site, yield was 43.5 bu/a in strip-till compared to 41.5 bu/a in a no-till system (Randall et al., 2001).

Benefits of Strip till

Strip till warms the soil, it allows an aerobic condition, and it allows for a better seedbed than no-till. Strip-till allows the soil’s nutrients to be better adapted to the plant’s needs, while still giving ground coverage to the soil between the rows. The system will still allow for some soil water contact that could cause erosion, however, the amount of erosion on a strip-tilled field would be light compared to the amount of erosion on a conventionally tilled field. Furthermore, when liquid fertilizer is being applied, it can be directly applied in these rows where the seed is being planted, reducing the amount of fertilizer needed while improving proximity of the fertilizer to the rootzone. Compared to conventional tillage, strip tillage saves considerable time and money. Strip tillage can reduce the amount of trips through a field down to two or possibly one trip when using a strip till implement combined with a planter. This can save the farmer a considerable amount of time and fuel, while reducing soil compaction due to few passes in a field. With the use of GPS guided tractors, this precision farming can increase overall yields.

External links

• Considering Strip-tillage