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In spite of potential benefits and positive assessments of reducing primary tillage operations, only a small part of irrigated row crops is currently managed using reduced tillage, for reasons that include concerns about its agronomic suitability for certain crop rotations. Three years of a tomato/corn rotation under standard and no-tillage management were used to understand the fate of a fertilizer and cover crop nitrogen (N) application. Uptake of both inputs was reduced under no-tillage during the year of application, in this case a tomato crop. As a result, more input N was retained in the soil in this system. The initial challenge of reduced tomato yields diminished as no-tillage management remained in place and the soil N reservoir developed. Corn production was not affected by tillage treatment. Inclusion of a legume cover crop increased the amount of fertilizer N retained in the soil over time, more so under no-tillage than under standard tillage, emphasizing the benefit of cover crops in reducing the amount of fertilizer required to maintain productivity. While acceptance of reduced tillage ultimately depends on economic performance, the results of this study support its agronomic viability for irrigated row crops.

Effect of tillage and crop residue management on soil properties, crop performance, energy relations and economics in greengram (Vigna radiata L.) was evaluated under four maize-based cropping systems in an Inceptisol of Delhi, India. Soil bulk density, hydraulic conductivity and aggregation at 0–15 cm layer were significantly affected both by tillage and cropping systems, while zero tillage significantly increased the soil organic carbon content. Yields of greengram were significantly higher in maize–chickpea and maize–mustard systems, more so with residue addition. When no residue was added, conventional tillage required 20% higher energy inputs than the zero tillage, while the residue addition increased the energy output in both tillage practices. Maize–wheat–greengram cropping system involved the maximum energy requirement and the cost of production. However, the largest net return was obtained from the maize–chickpea–greengram system under the conventional tillage with residue incorporation. Although zero tillage resulted in better aggregation, C content and N availability in soil, and reduced the energy inputs, cultivation of summer greengram appeared to be profitable under conventional tillage system with residue incorporation.

CONTINUOUS cropped winter wheat was successfully man-aged with furrow irrigation by use of limited tillage and chemical weed-volunteer control on the Southern High Plains. No-till had slightly higher yields and irrigation water use efficiency than did clean tillage. The yield increase with no-till was generally offset by additional cost of herbicides. Limited tillage seemed more practical and dependable as an alternative to clean tillage. No-till and limited tillage reduced time and fuel requirements by 50 and 40 percent, respectively.

(...) The newly developed wing-chisel has been effective in the once-over desiccation of stubble from recently harvested crops. Additional benefits have included deep tillage to break any existing hardpan, controlled tractor traffic by using the chisel as an in-row implement for a ridge-till planting configuration, increased infiltration rates, and maintaining plant residue on soil surface. (...)

Field and laboratory experiments were conducted on a crusting loess soil in the northern Negev (Israel) with the aim of improving the efficiency of the use of rain by row crops, either in dryland or irrigated farming, and to decrease erosion. The specific objective of the experiments described was to develop methods that enhance infiltration of rainfall during the winter fallow season in an area with a mean annual rainfall of 400 mm which is subject to wide variation. It was found that the traditional tillage system consisting of deep ploughing (35–45 cm) of dry soil in the fall followed by disking, smoothing and ridging is the worst choise as it could result in runoff losses of as much as 60% of the rainfall, accompanied by accelerated erosion. This water loss can be critical to the success of dryland cotton and also determines whether or not a pre-irrigation of about 25% of the total annual water allotment must be given to irrigated cotton. The traditional practice was compared with: deep ploughed land left fallow during the entire rainy season; ridging after subsoiling instead of deep ploughing; subsoiling and ridging carried out in one minimum tillage operation; direct ridging without primary tillage and basin tillage of ridges following either deep ploughing, subsoiling or minimum tillage. This study showed that by far the most effective method for enhancing infiltration and eliminating runoff was the basin tillage system. The method is adaptable both to mechanized farming and to farming based on animal power or manual labour, and its application can ensure success where rainfall is limiting. It was found that laboratory characterization of soil hydraulic properties with a static rainfall simulator allows prediction of runoff on crusting soils. This means that the need for, and the effectiveness of, conservation measures may be estimated using disturbed soil samples, which is quicker and cheaper than field tests.

Three tillage systems for soybeans in the Western Corn Belt were compared: conventional, reduced-till, and no-till. Production budgets are presented for various assumptions on the relative yields under these three systems. Energy output-input ratios were favorable for the reduced-till and no-till systems. For a model corn-soybeans-hog farm, these two systems were also more profitable than conventional tillage at 1976 crop and input prices.

DEFINITIONS Conventional tillage consists of several operations involving the moldboard plow, springtooth harrow, disk harrow, cultivator and other types of equipment. The ground is tilled to produce a smooth and fine seedbed. Reduced tillage is a technology practiced by an increasing num­ ber of farmers today. It involves the elimination of as many of . these operations as is technolog~~ally, biologically and econom­ ically feasible . The different types of reduced tillage can range from systems involving chisel plowing the ground in place of moldboard plowing to no-tillage. Under no-tillage, the seed is placed in soil that still carries the previous crop's residue. Weed control is accomplished through herbicides and the old crop resi­ due serves as a mulch which suppresses weed growth. Reduced tillage can reduce the amount of labor needed on a farm . In re­ duced tillage systems where the plowing operation is eliminated, crop residues left on top of the soil reduce moisture loss and soil erosion by wind and water. Legume cover crops can be used to supply nitrogen and provide a mulch cover.

Publisher Summary This chapter discusses the relation between conservation tillage and sustainable agriculture, and identifies appropriate conservation tillage systems for different soils, crops, and agroecological region. Conservation tillage is a generic term encompassing many different soil management practices. It is generally defined as any tillage system that reduces loss of soil or water relative to conventional tillage and often a form of noninversion tillage that retains protective amounts of residue mulch on the surface. Timing of tillage operations can also be adjusted to facilitate operations during the periods of peak labor demand. The latter includes practices such as plowing at the end of rains in the tropics and fall plowing followed by spring disking in temperate zone. A no-till system has proved effective for soil and water conservation and for production of pastures and grain crops on Alfisols prone to crusting and accelerated erosion in Northern Territory, Australia. There are subtle differences in tropical vis-a-vis temperate regions that must be considered when assessing the applicability of the no-till system. It is found that for soils prone to crusting and hard-setting, shallow tillage without inversion and with the crop residue retained on the surface as mulch is the most appropriate conservation tillage.

Publisher Summary This chapter reviews the tillage system effect on yield for corn and soybean production in the United States corn belt. The tillage-planting system includes preplant tillage, planting, and weed control by cultivation, herbicides, or both. The tillage system also affects methods of fertilizer and insecticide application. Three types of tillage-planting systems––namely, high-energy systems, moderate-energy systems, and low-energy systems are described in the chapter. Moderate-energy tillage systems can be substituted for high-energy systems on most soils without yield penalty if pests can be controlled. Low-energy tillage systems appear to be well adapted to the rolling soils of the southern corn belt and the well-drained loams and coarser textured soils of the northern corn belt if pests are controlled. Low-energy tillage has not been well adapted to poorly drained soils. The chapter discusses various yield factors influenced by tillage-planting system—including (1) early planting, (2) soil compaction, (3) weed control, (4) fertilizer placement, (5) moisture conservation, (6) soil erosion prevention, (7) insect and disease control. The chapter estimates cultural energy requirements for various systems and soil types, including energy requirements for herbicides. Energy estimates are given for low, medium, and high-draft soils.

The energy requirements of three tillage systems for corn and soybean production in Virginia–conventional, reduced, and no-till–are compared. Data are given on energy use for tillage and planting, manufacture and maintenance of tillage machinery, manufacture of insecticides, herbicides, and fertilizers, and manufacture, maintenance, and operation of harvesting equipment. Compared to conventional tillage of corn, the reduced tillage and no-till systems result in an energy saving equivalent to 1.4 and 4.1 gallons of diesel fuel per acre respectively. For soybeans, the corresponding figures are 1.2 and 5.0 gal/A.

Precision Farming equipment is more and more common on modern, large scale farm enterprises. With basic equipment being available, an important condition for the use of site-specific approaches is given. Site-specific approaches may help to increase the efficiency of a farm enterprise, as well as may help to achieve certain, predefined goals. A site-specific tillage strategy focusing on soil conservation was developed and evaluated. Online inclination data and local available biomass, calculated from yield maps, was used to compute necessary working depth for each unit area of a site. A control-unit controlling an electronic valve for two hydraulic cylinders fitted with displacement transducers and an on-board computer system implemented the calculated working depth online. While working precision was excellent, the time span require to switch between two working depths can be optimized.

Arable farming is searching for ways of reducing inputs of resources in the highly competitive world market of plant production. Also, there is a need to ease the impact of peak-load periods in the autumn due to the establishment of winter crops, by applying low-input and high-capacity machinery systems. These demands may be fulfilled by the adoption of modern techniques and methods of reduced tillage. Operational performance data and resource input involved with the newest types of stubble cultivators and seed drills are lacking. Generalised task models integrating parameters derived from farm studies were used to evaluate the operational performance and operations costs of the range of operations involved with crop establishment. By applying the models to a number of machinery systems and tillage scenarios, the operational competitiveness of including the newest types of stubble cultivators and seed drills were indicated. Simulations showed that in the case of reduced tillage the energy input was reduced by 18–53% compared with conventional soil tillage, depending on the methods and techniques used. Direct drilling reduced the energy input by 75–83% and labour demand and CO2 emissions would be reduced by approximately the same percentage. Based on model comparisons, reduced tillage with no ploughing as part of the crop establishment and plant care caused 25–41% reductions in the cost per hectare compared with traditional methods. These cost reductions required full capacity utilisation, as lesser utilisation would increase unit costs.

The objective of this study was to investigate the effect of tillage and cropping system on near-saturated hydraulic conductivity, residue cover and surface roughness to improve soil management for moisture conservation under semiarid Mediterranean conditions. Three tillage systems were compared (subsoil tillage, minimum tillage and no-tillage) under three field situations (continuous crop, fallow and crop after fallow) on two soils (Fluventic Xerochrept and Lithic Xeric Torriorthent). Soil under no-tillage had lower hydraulic conductivity (5.0 cm day−1) than under subsoil tillage (15.5 cm day−1) or minimum tillage (14.3 cm day−1) during 1 of 2 years in continuous crop due to a reduction of soil porosity. Residue cover at sowing was greater under no-tillage (60%) than under subsoil or minimum tillage (

An investigation of water conservation as affected by different primary tillage methods was conducted on a soil of the Doveton series (fine-loamy, mixed, thermic family of Rhodic Paleudults), where a direct sampling technique was used to monitor the soil-water profiles. Soil samples were taken for the period just prior to early winter tillage to two weeks before the maize crop flowered. The results showed that tillage practices which maintain higher levels of surface residues retained more water than practices which by their mode of soil disturbance leave soil surfaces relatively ‘clean’. Measured differences in soil physical properties and possibly also surface residue distribution resulting from tillage were used to explain why reduced tillage systems provided better water conservation. S. Mr. J. Plant Soil 1985, 2: 21–26

THE ambiguity of current tillage nomenclature has led to much confusion. This report explains a uniform, comprehensive tillage index that was developed to avoid that ambiguity. It is based on row topography, residue cover, roughness, and tillage depth that result from passage of the tillage tool rather than on the tillage tool used. Examples of the use of this tillage index are presented. This index, because of its percentage crop residue cover and potential surface water storage components, will be useful when the Universal Soil Loss Equation is to be used for estimating erosion potential on a given field

For many centuries, crops have been produced with tillage systems that manipulate the soil a number of times. The tillage system often employed in the production of row crops might involve plowing, one or more diskings, then one or more cultivations after crop emergence. Such a system is usually referred to as a conventional tillage system.

Three tillage systems: conventional tillage, ridge tillage, and no-tillage are evaluated using stochastic dominance with respect to a function analysis. Each tillage system is evaluated for three cropping patterns: continuous grain sorghum, continuous soybeans, and soybeans after grain sorghum. Conventional tillage continuous grain sorghum would be preferred by risk averse managers, although small changes in production costs and yield differences could lead to indifference between a no-tillage system and the conventional tillage system.