Reduced Tillage Systems for Crop Production

• A reduction in tillage intensity is being observed in many major crop production areas around the world.
• Reduced tillage can minimize fuel and labor costs while maximizing soil and moisture conservation.
• Success with reduced tillage depends on uniform residue distribution, proper planter adjustment, adequate nutrient management and effective weed control.
• This article reviews advantages and disadvantages of various tillage systems and offers practical suggestions for getting started with reduced tillage systems.

For generations, farmers have tilled the soil to prepare it for crop production. In recent years, however, the intensity of tillage has decreased and the land area under conservation tillage has increased significantly in many areas. Global cropland area using no-till has increased from less than 150 million acres in 2000 to over 220 million acres in 20041. This is undoubtedly due to the many benefits conservation tillage offers crop producers, including reduced labor requirements, reduced fuel requirements and conservation of soil and water.

Moldboard plowing was the most used method of primary tillage for many years. Its main advantage was its suitability to most soil types including poorly-drained soils. But its disadvantages, including high fuel and labor costs, and the potential for soil erosion and soil moisture losses, have caused many crop producers to select other tillage systems. The chisel plow and other similar primary tillage tools have many of the same advantages and disadvantages as the moldboard plow, but generally leave more crop residue on the soil surface which can reduce soil erosion potential.

While no-till may not be well-suited to some poorly-drained soils, it has many advantages over more intensive tillage methods. No-till minimizes fuel and labor costs while maximizing soil and moisture conservation. Advantages and disadvantages of several tillage systems are summarized in Table 1.

Table 1. Tillage System Comparisons

Modifications of the no-till system, such as strip-till, have been developed to take advantage of the positive aspects of no-till while minimizing the disadvantages.

Conservation tillage provides many benefits to crop producers. The list of benefits below was developed by the Conservation Technology Information Center² at Purdue University.

• Reduces labor, saves time
• Saves fuel
• Reduces machinery wear
• Improves soil tilth
• Increases organic matter
• Traps soil moisture, improves water availability
• Reduces soil erosion
• Improves water quality
• Increases wildlife
• Improves air quality

Savings in labor and fuel costs have been documented by University of Nebraska personnel as shown in Tables 2 and 3.

Table 2. Tillage System Diesel Fuel Requirements (gal/acre)³

Table 3. Tillage System Labor Requirements (min/acre)³

Environment: Temperature and rainfall patterns of an area provide the foundational information for understanding what type of tillage systems are likely to be most successful. Is rainfall generally limiting or is excess moisture a consistent problem? This environmental information, coupled with field-specific soil characteristics, establishes the fixed parameters that must be considered when designing a crop management system. If rainfall is typically limiting or temperatures are relatively high, chances are good that a reduced tillage system will work well. Design your cropping system to take full advantage of existing environmental conditions.

Soil Characteristics: Soils with good surface drainage are more suited to no-till and other reduced tillage methods. Soils with good internal drainage are also more suited to less intensive tillage practices. Good surface or internal drainage can offset the lack of the other, but if both internal and external drainage are limiting, reduced tillage systems face significant challenges. Try reduced tillage systems first on fields with good drainage.

Crop Rotation: While mono-cropping in reduced tillage systems is certainly possible, chances of success are greater when a variety of crops are used in the rotation. Numerous studies have shown that no-till, continuous corn will not yield as well as no-till corn rotated with other crops, particularly a legume such as soybean or alfalfa. This diversity of crops in the rotation is most important on poorly-drained soils. In moisture-limiting environments, cropping intensity is also an important consideration. No-till increases the amount of water available to the crops, so more intense rotations can be used to utilize this extra water. When reducing the intensity of your tillage system, consider a crop rotation including some diversity.

Crop Selection: Reduced tillage systems like no-till have been used successfully in many crops including corn, sorghum, wheat, sunflowers, canola, cotton and soybean. In each case, success depends on uniform distribution of residue from the previous crop, proper planter adjustment and stand establishment, adequate nutrient management, and an effective weed control program.

Hybrid or Variety Selection: Although the best-performing corn hybrids in one tillage system are generally the best-performing hybrids in another tillage system, hybrid selection remains critical to success with reduced tillage. Choose hybrids or varieties with good emergence, early vigor and disease resistance.

Residue Management: Uniform residue distribution while harvesting the previous crop is extremely important. Residue that has not been properly distributed can make uniform stand establishment very challenging for any planting equipment. Row cleaning devices for in-row residue removal can improve stand establishment in environments where high soil moisture and low soil temperature typically delay seedling development. When planning to implement a reduced tillage system, be prepared to uniformly distribute crop residue at harvest and have a planter equipped to perform in high residue situations.

Planter Adjustment: Planter adjustments important for success with reduced tillage systems include: keep planter units level, ensure down pressure is adequate, adjust coulters so they cut residue but don't run too deep, adjust residue managers to move residue but not soil, ensure seeding depth is uniform and the seed furrow is closed - providing good seed-to-soil contact.

Weed Control: Be prepared for an increase in perennial weeds and small-seeded weeds. Start clean - don't plant into a dense mat of live weeds. Control weeds and previous perennial crops with a herbicide application before planting. Be sure to have a post-emergence herbicide plan in place. Where they are available, herbicide-tolerant crops can help.

Nutrient Management: Regular soil testing is important in any tillage system, but is critical before establishing a reduced tillage system such as no-till. Collect soil samples and apply and incorporate any P, K and lime required before converting a field to no-till. Minimize the risk of N losses with proper placement and timing of N applications. While nutrients can be surface applied in no-till systems, injection may help minimize losses and improve plant availability.

Soil Compaction: Minimize soil compaction by controlling traffic. Confining wheel traffic to specific areas can reduce root growth limitations caused by excess soil compaction.

Insects and Diseases: Selecting hybrids or varieties with good resistance to the most common local diseases and insects is very important for reduced tillage systems. Crop rotation can be very beneficial to break insect and disease life cycles. Monitor crops closely to detect problems that can be corrected during the growing season. Where available, crops with built-in protection against corn borers or rootworms have proven to be very effective. Insecticide seed treatments can also provide insect protection.

Irrigation: No-till conserves moisture and increases the efficiency of irrigation water. While flood irrigation systems may limit the type of reduced tillage system used, overhead sprinklers are well suited to no-till.

Snow Catch: Increasing the height of stubble from the previous crop can maximize snow catch in no-till systems. Be sure to utilize all available sources of water in moisture-limiting environments.

Manure Management: When livestock are part of the agricultural system, be sure to take advantage of the benefits of applied manure. If surface applications are made, be sure applications are uniform. Manure injection can help minimize nutrient losses while maintaining surface residues for maximum soil and moisture conservation.

Cover Crops: Cover crops can play a major role in building soil organic matter. Cover crops can help improve the chances for no-till success in soils that are low in organic matter and susceptible to compaction.

Rotational Tillage: Some growers use different tillage systems for different crops and this may be beneficial on poorly-drained soils. Remember that the organic matter gains from reduced tillage will be lost when tillage intensity is increased.

The ideas below can improve the chances of success when trying a new reduced tillage system: Seek advice from other growers who are successfully using a reduced tillage system. Communicate with soil scientists or others who might be conducting tillage system research. Attend plot tours or field days demonstrating tillage methods. Join a tillage club or grower association focused on reduced tillage. Plan carefully for crop rotation, residue distribution, use of planter attachments, fertilizer application and herbicide program. Conducting on-farm research is one way to gain personal experience and learn what works and what doesn't. Attend tillage-related conferences or workshops. Seek additional information from the web sites listed below, or from other sources. Contact your Pioneer agronomist for further information.

1. Dan Towery. Conservation Technology Information Center. Personal communication. 2004.
2. Conservation Technology Information Center.
3. Conservation Tillage and Planting Systems. University of Neb., G91-1046.

• African Conservation Tillage Network:
• Western Australian No-Till Farmers Association:
• Conservation Technology Information Center:
• Dakota Lakes Research Farm - Pierre, SD:
• European Conservation Agriculture Federation:
• FAO Conservation Agriculture:
• Irrigation Research Foundation - Yuma, CO:
• Kansas State University No-Till page:
• Manitoba-North Dakota Zero Tillage Farmers Association:
• No-Till Farmer:
• No-Till on the Plains:
• Pacific Northwest Direct Seed Association:
• Rolf Derpsch (Latin America No-Till):
• South Dakota No-Till Association:
• Southern Conservation Tillage Conference: