Is Conservation Tillage A Viable Option in the CIS?

Transcription

1 Aug 13, 1998 Is Conservation Tillage A Viable Option in the CIS? By Jitendra Srivastava and Evan Meyer

2 Table of Contents I. Executive Summary 2 II. Introduction 5 III. Conservation Tillage 7 IV. Similarities in Agro-Climatic and Ecological Conditions Between North America and CIS Countries 22 V. Possibilities for Adoption of Conservation Tillage in CIS...25 References.29 LIST of TABLES Table 1 Soil loss in comparison to residue cover..7 Table 2 Advantages, disadvantages, and typical field operations for selected tillage systems..8 Table 3 Diesel fuel requirements for various tillage systems 15 Table 4 Comparative labor costs 16 Table 5 Yields from Ukrainian Minimum conservation methods..19 Table 6 Climactic similarities in CIS and North America 22 Table 7 Soil types in CIS and North America...23

3 Executive Summary Conservation tillage an assortment of reduced tillage practices such as no-till, ridge till, chisel plowing, and mulch till reduces soil erosion and production costs, while maintaining or increasing productivity. There are many similarities in climate and agroecological conditions between North America and the Commonwealth of Independent States (CIS). North American conservation tillage technologies, practices, and policies provide examples that could be modified to fit the agricultural needs of the CIS. Conservation tillage practices are vital in an area of the world striving to improve efficiency and achieve profitability in farming systems. Agriculture in the CIS is facing problems of efficient, economical, and sustainable production. Old machinery is often in a state of disrepair. A mentality focused on production has often neglected issues of sustainability. As a result many practices are leading to lower soil fertility, erosion, and soil compaction. Various terms for conservation tillage create confusion about what the term stands for. According to the 1985 and 1990 U.S. Farm Bill, conservation tillage is classified as any practice that leaves a minimum of 30% crop residue on agricultural fields. No-till, ridge till, mulch till, and reduced tillage fall under this definition. All of the tillage systems offer both advantages and disadvantages in different circumstances. No one tillage system is ideal for all soil, climate, and crop conditions. Conservation tillage practices offer a variety of options to meet different conditions that include: Farming systems Agrochemical use Crop sequence Topography Soil type and water conditions Corn, soybeans, wheat, and cotton are the most common crops in conservation tillage. However, many other crops have been successfully farmed using these techniques. Conservation tillage offers benefits such as: Reduced labor requirements Time Savings Reduced machinery wear Fuel savings Better long term production Improved water quality Decreased erosion 2

4 Higher soil moisture Improved water infiltration Decreased soil compaction Improved soil tilth More wildlife and biological activity Reduced release of carbon gases Reduced air pollution Russian, Ukrainian, and Moldovan conservation tillage practices are examined. Examples of North American farmers who have successfully implemented conservation tillage practices, while minimizing or eliminating agrochemical use are provided. Effective means for promoting conservation tillage through farmer to farmer exchanges is examined in a case study of Brazil. While conservation tillage offers many advantages it does require a change in agricultural practices. In some respects conservation tillage requires more intensive management skills. Barriers that exist in switching to conservation tillage are: Cultural barriers Reluctance to reduce plowing Fear of switching to a new production system Economical Initial cost of conservation tillage machinery Potential increased chemical fertilizer and herbicide use Management Weed management Pest management Disease management Residue management Fertilization management Maintaining yields Soil temperature and moisture While these issues are legitimate concerns to farmers, if properly managed they should pose little or no problems. Culturally, farmers in the CIS are used to plowed fields free of crop stubble and residue. Programs to increase their consciousness will be needed to help increase farmer awareness of the need for conservation tillage and its place in a productive agricultural system. Increased herbicide use and costs may be economically prohibitive to farmers in the CIS. However, with proper management and innovative techniques herbicide and chemical fertilizer use can be kept to a minimum. While excellent researchers and institutions exist, they lack the funds to carry out effective research. Government policies evaluating an environment for greater adoption of conservation tillage is required. The cost for purchasing conservation tillage equipment 3

5 may be discourage individual farmers. However, the initial large investment in equipment should pay for itself in economic savings and efficient production. In North America government agencies, policies, universities, and farmer organizations have played a role in promoting conservation tillage. In addition to environmental benefits economic benefits also play a role in conservation tillage acceptance. These savings are realized in three forms: Savings in fuel, labor, and lower depreciation and maintenance costs for agricultural machinery. Fuel costs can be reduced by 25%, while depreciation in machinery is less than in conventional tillage due to less use and wear and tear on the machinery. The World Bank can play a crucial role in promoting conservation tillage in the CIS. The Bank can work with government officials in the CIS to generate effective national policies encouraging conservation tillage, and provide funds available to implement these policies. These funds can be distributed amongst research institutions and low interest loans or grants to purchase conservation tillage equipment could be made available. These may include provision of machinery testing and demonstration of location specific technologies and training. Programs that raise awareness about conservation tillage benefits should be funded as well. In addition programs that provide exchange of North American academics and farmers with conservation tillage experience could help promote conservation tillage. 4

6 Introduction Conservation tillage, a term used to describe various minimum tillage operations are effective technologies for reducing soil erosion, while maintaining or increasing productivity, improving soil conditions, and realizing economic benefits. North America conservation tillage technologies, practices, and policies provide a viable option for the CIS due to similarities in climate and agroecological conditions. Conservation tillage practices are vital in an area of the world striving to improve efficiency and achieve profitability in farming systems. However, many barriers stand in the way. This document attempts to explore conservation tillage practices in North America and their applicability for similar conditions in the CIS. Significant political and economic changes have occurred in the CIS in the 1990 s. These new countries have struggled to move from state controlled to market economies. The legacy of state directive and management style still predominates on many large and partially privatized farms. Many of these farms operate at low efficiency and are struggling financially. At the same time private farms have increased production. These private farms produce a disproportionately large amount for the small amount of land they occupy (Csaki and Nash, 1998). Much of the agricultural machinery in the CIS is in a state of disrepair. The use of this machinery plays a large role in unsustainable agricultural practices leading to soil erosion, compaction, and decreased fertility. Replacing this machinery with conservation tillage equipment would help to improve agricultural production and sustainability (Cameron and Oram, 1995). Agriculture production in the Soviet Union was based on central directives. The result was a focus on production, which often came at the expense of sustainability. Often farms would attempt to meet production goals, even if unrealistic. Soil conservation was widely neglected. Marginal areas were farmed in order to boost production. Various problems of sustainability arose from these practices. Amongst them were decline in soil fertility, soil erosion, and soil compaction. Many of the practices that have led to these problems remain in use. Soil fertility and organic matter is declining as a result of tillage and agricultural practices that neglect to incorporate sufficient organic material into the soil. Deep tillage techniques play a major role in this process (Puterbaugh, 1993). As a result of heavy tillage practices soil fertility has declined by as much as 50%. Humus in Chernozem soils has gone from 10-13% to 5% (Cameron and Oram, 1995). While these soils still contain adequate organic matter, the declining humus and fertility indicate a trend that needs to be reversed. Low soil fertility is exacerbated by the little amount of organic matter produced and returned to the soil in areas of low rainfall and productivity, such as marginal agricultural land in Kazakhstan (Libert, 1995). These lands are fragile and came into production from in an effort to increase agricultural production. While some of the land can be used for agricultural purposes its use needs to be moderated and appropriate agricultural management practices need to be found. However, some of this 5

7 marginal land is unfit for agricultural production (Libert, 1995). Soil erosion is a major problem affecting agricultural production in the CIS. An estimated 327 million ha of land have been severely effected by wind and water erosion (Nazarenko, 1993). Thirteen million gullies on agricultural land total 6.6 million ha. Approximately 150,000 ha of land annually are severely damaged by water erosion (Libert, 1995). In Russia alone 60 million ha of agricultural land is affected by erosion. Little funds exist to implement erosion prevention methods. An estimated 50% of arable land in the Ukraine is sufficiently steep to warrant water erosion as a major problem (Cameron and Oram, 1995). On average tons of topsoil are lost per hectare per year. Wind erosion alone accounts for a loss of two to three billion tons of fine topsoil a year. Agricultural yields are affected to varying degrees depending upon the severity of erosion. On soils with minor erosion, yields have declined by 15-20%, areas with moderate erosion suffer 30-40% drop in yields, and severely eroded lands suffer a 50-60% drop in yields (Nazarenko, 1993). A secondary effect of soil erosion is siltation of rivers and reservoirs. In many cases the reservoir capacity of water systems are greatly reduced by siltation. The Volga reservoirs have decreased by one third as a result of siltation (Libert, 1995). Existing practices and heavy machinery are leading causes of soil compaction. Approximately 170 million hectares of land has been affected by soil compaction. Inflexible operation procedures and short window period for tilling and harvesting coincide with extreme weather often result in tilling and plowing operations during wet periods. Ineffective machinery needs to make more trips over the soil in order to prepare it. On the average seven passes are made over the soil to prepare it for planting. Estimated losses as a result of soil compaction differ. Conservative estimates calculate a production loss of 15 million tons of grain, two million tons of sugar beets, and 500,000 tons of maize (Libert, 1995). While other estimates calculate a 16-27% decrease in production as a result of soil compaction, with a loss of 50 million tons in grain production alone (Nazarenko, 1993). 6

8 Conservation Tillage Conservation tillage has been applied across North America in an effort to drastically reduce erosion, while maintaining or increasing yields. Various terms for conservation tillage create confusion about what the term stands for. According to the 1985 and 1990 U.S. Farm Bill, conservation tillage is classified as any practice that leaves a minimum of 30% crop residue on agricultural fields. No-till, ridge till, mulch till are the three practices that fall under this definition (Hill, 1996). Several variants exist within these practices. However, most importantly conservation tillage is not one system but many systems adapted to make high-residue farming provide as many of the economic and environmental benefits as it can on a particular site. Conservation tillage can reduce soil erosion by up to 91% (McCain and Towery, 1996). Table 1: Soil loss in comparison to residue cover Residue Cover % Runoff Soil loss ton/acre Source: Janssen and Hill, 1994 No-till creates minimal soil disturbance by using machinery to chop down residue and then to cut a slit in the soil where the seed is injected and then covered over. Herbicides are sprayed to control weeds. In emergency cases cultivation is used (Janssen and Hill, 1994). No-till is ideal for highly erodable soils. Sloped areas and soils that are sandy loams with average or poor water retention capacity are good places for no till. Strip tillage is very similar to no-till except that a strip is cleared and sometimes the soil is deep tilled. The advantage of strip till is that it improves drainage and helps to heat up soils quicker (Janssen and Hill, 1994). Ridge till creates slightly more soil disturbance than no-till. Sweeps, disk openers, coulter, or row cleaners prepare ridges. Areas with irrigation have used ridge till for better drainage. The advantages that ridge till offers is decreased herbicide costs and the flexibility to incorporate manure into ridges, helping to offset fertilizer costs. Another advantage of ridge till is that the ridges heat up and dry sooner allowing crops to be planted earlier, offering them a competitive advantage over weeds. This is particularly important in colder regions where residue during spring keeps soil at a lower temperature resulting in delayed germination (Janssen and Hill, 1994). Chisel plows, field cultivators, disk sweeps, or blades till the soil in mulch till systems. Soil is not turned over but simply broken up. Different techniques determine the amount of residue left over. Herbicides and/or cultivation are used to control weeds. The success of mulch till is determined by the amount of residue, surface roughness, and tillage direction (Janssen and Hill, 1994). Chisel plowing offers the advantage of breaking up 7

9 soil similar to the way done by moldboard ploughs, without inverting the soil. This is particularly important in compacted soils. Stubble mulching or no-till eco-fallow is a modified conservation tillage practice for areas of low rainfall. Whereas conventional tillage practices in semi-arid prairies heavily rely on fallowing to maintain soil productivity, eco-fallow systems are able to increase agricultural productivity. Reduction in tillage helps to increase soil moisture, increasing the land s capacity to produce. A more intensive crop production system can be implemented. Depending on soil moisture different crops with differing water needs can be used. This practice is particularly suited for wheat, sunflower, and grain sorghum. Crop rotation and adequate weed control are a core element of this practice (Hill, 1996). All of the tillage systems offer both advantages and disadvantages in different circumstances. No one tillage system is ideal for all soil, climate, and crop conditions. Conservation tillage equipment is lightweight and can be pulled by a lightweight tractor. This offers the advantage of reducing and virtually eliminating soil compaction. Following up criteria could be taken into consideration while selecting a tillage system: Soil and cropping situation Crop sequence Topography Soil Type and weather condition Chemical fertilizer and herbicide use In certain situations tillage rotation offers the advantage of matching different conservation tillage techniques with the most ideal crop. For example following no-till after soybeans, and using chisel plow after corn. The drawback of such a system is that the soil disturbance eliminates the benefits of a no-till or ridge till situation where soil structure and tilth is greatly improved through minimized soil disturbance. (Jasa et al. 1991) Table 2: Advantages, disadvantages, and typical field operations for selected tillage systems System Moldboard Plough Chisel Plow Typical Field Operations Fall or spring plow; one or two spring diskings or field cultivations; plant; cultivate. Fall chisel; one or two spring diskings or field cultivations; plant; cultivate Major Advantages Suited to most soil and management conditions. Suitable for poorly drained soils. Excellent incorporation. Welltilled seedbed Less erosion than from cleanly tilled systems. Less winter erosion potential than fall plow or fall disk. Well adapted to poorly Major Disadvantages Little erosion control. High soil moisture loss. Timeliness considerations. Highest fuel and labor costs. Larger number of operations cause excessive soil erosion and moisture loss. In heavy residues, stalk shredding may be 8

10 Disk Ridge Plant No-Till Source: Jasa, 1991 Fall or spring disk; spring disk and/or field cultivate; plant; cultivate Chop stalks (on furrow irrigation); plant on ridges; cultivate to rebuild ridges. Spray; plant into undisturbed surface; post emergence spraying or cultivation as necessary. drained soils. Good to excellent incorporation. Less erosion than from cleanly tilled systems. Well adapted for lighter to medium textured, well-drained soils. Good to excellent incorporation. Excellent erosion control if on contour. Well adapted to poorly drained soils. Excellent for furrow irrigation. Ridges warm up and dry out quickly. Low fuel and labor costs. Maximum erosion control. Soil moisture conservation. Minimum fuel and labor costs. necessary to avoid clogging of chisel. Larger number of operations cause excessive soil erosion and moisture loss. In heavy residues, stalk shredding may be necessary to avoid clogging of chisel. No incorporation. Creating and maintaining ridges. Narrow row soybeans and small grains not well suited. No incorporation. Increased dependence on herbicides. Not well suited for poorly drained soils. Of the three practices that fall under the category of conservation tillage, mulch till is the most widely applied practice with approximately 57,525,400 acres in mulch till in the United States. No-till follows behind with 42,889,400 acres in no-till. Ridge till is only practiced by a limited group of farmers amounting to 3,400,220 acres. These three practices combined amount to 35% of all agricultural land in the United States. Reduced tillage practices that leave at least 15% of crop residue on the ground account for 25.7% of agricultural land accounting for 74,99,100 acres. (CTIC National Crop Residue Management Survey, 1996) In Canada zero till (the Canadians term for no-till) is not widely practiced. In the semi-arid prairies as little as 2% of farmers implement no-till practices. However, an estimated 70-80% of farmers practice mulch tillage (Cameron and Oram, 1995). Out of all the above practices no-till is experiencing the most rapid growth. From 1989 to 1996 land under no-till went from 14,148,144 (making up 5% of agricultural land) to 42,889,400 in 1996 (making up 14.78% of agricultural land) in the U.S. This can be attributed to various factors. No-till is a relatively easy practice to put into use. Research and extension with no-till has also been fairly intensive. A decrease in the cost of the herbicide roundup (glyphosate) has made no-till a more affordable practice. Many farmers prefer no-till because it reduces the amount of labor necessary to plant. In areas of the United States where farming is becoming a part time profession no-till allows farmers to plant their crop without missing too much time from their other jobs. (Walker, personal communication, 1998). No till has received a great deal of funding for research and promotion on the part of chemical and machinery companies interested in promoting their products. Other practices such as ridge till have received less focus and funds. 9

11 Conservation Tillage in Relation To Various Cropping Systems Conservation tillage technology is expanding and growing at a rapid rate. However, the most widely planted crops under conservation tillage are corn, soybeans, and wheat. At the present, cotton is the fastest growing crop under conservation tillage. Other crops that have been used under conservation tillage systems include: Canola, rape, mustard, sunflower, flax, coriander, and chickpeas (Cameron and Oram, 1995). Currently, experiments are at an advanced stage for planting no-till vegetables. Management Aspects of Conservation Tillage While conservation tillage offers many advantages it does require a change in agricultural practices. In some respects conservation tillage requires more intensive management skills. If certain elements are not managed correctly problems can occur. Farmers have often expressed concern over the management of various factors in conservation tillage. Amongst these are: Weed management Pest management Disease management Residue management Fertilization management Maintaining yields Soil temperature and moisture While these issues are legitimate concerns to farmers, if properly managed they should pose little or no problems. In order to be fully effective conservation tillage needs to be practiced alongside other agricultural methods. This means that many practices that coincide with good agricultural management practices under conventional tillage hold true for conservation tillage. Many farmers express concern and resistance to switching to a new tilling system from the one with which they are familiar. Legitimate concerns about increased herbicide costs, increased weed, pest, and disease problems are common doubts expressed by many farmers. Conservation tillage demands a change in practices and mindset from conventional tillage systems. Adjustments have to be made in machinery, planting, fertilizer use, and crop sequence. Certain problems can arise in adjusting to a new system. However, these problems can be avoided by adopting practices that complement conservation tillage practices and prevent potential problems. Amongst these practices include an effective Integrated Pest Management program should include strong components for managing weeds, diseases, and pests. The appropriate incorporation of an effective crop rotation, residue management program, and cover crops can help make for a smooth transition into the use of conservation tillage. 10

12 Integrated Weed Management Conservation tillage systems generally require more intensive weed management. Virtually all conservation tillage practices use various cultural practices as well as herbicides to control weeds. Systems such as no till only resort to cultivation to eliminate weed problems in emergency cases. Other conservation tillage techniques are more liberal with tillage use to control weeds. However, all drastically reduce the amount of cultivation in controlling weeds (Hill, 1996). One of the changes that occur in conservation tillage is a shift in weed problems from annual to perennial weeds. Large seeded weeds become less of a problem, while small seeded weeds generally become harder to control (Hill, 1996). Some farmers have been reluctant to switch to no till systems for fear that their decreased fuel and labor costs will be offset by increased herbicide costs. While initial herbicide use generally increase for the first few years, in a system that is well managed herbicide use is equal or less than in a conventional system. A case study discussed further in the paper documents a farmer who minimizes herbicide use through the use of cover crops (Hill, 1996). Many no-till farmers reduce herbicide use below recommended applications once they become familiar with no-till. These farmers usually do so after gaining a familiarity and comfort in their tillage system. In doing so they maximize their benefits by decreasing costs and the use of inputs. Once again it should be stressed that every situation is different, and in order to create an ideal conservation tillage system one needs to experiment and to a certain degree work through trial and error (Hofstetter, 1994). Some tillage systems have even succeeded in eliminating herbicide use. Innovative ridge till farmers have designed systems that rarely apply herbicide use, except in emergency cases. A case study further in the paper provides an example of one such farmer. Ridge till systems offer a viable option for decreased herbicide use. In the process of creating ridges soil is shaved off the top of the ridge knocking off 70% of the weed seeds. Some farms such as the Thompson Farm in Iowa use no herbicides but rely on the use of cover crops and light cultivation to control weeds. For the Thompsons the goal is to keep weed off the ridges. This often means that there might be weeds in the valleys, but as long as they remain there and not in the ridges they represent little competition to the crops (Pesek. et al, 1989). In the prairies of South Dakota research has focused on developing an ideal no-till system for semi-arid prairies. Part of this process is the control of weeds through various practices such as crop rotation, competition, and sanitation to control weeds. Intensified crop rotation has the result of increasing crop competition with weeds. Early planting, the use of narrower rows, and side dressing with fertilizer to give crops a jump start help crops outcompete weeds (Beck, 1997). 11

13 Sanitation is used to decrease weed pressure. The first factor that comes into play is the use of weed free seeds. Cleaning agricultural machinery between fields helps to reduce weed contamination from one field to the next. Cultivating and spraying along fence rows to prevent weed invasion is also of crucial importance. Spraying with herbicides following harvesting and planting helps to keep weeds in check (Beck, 1997). Other important strategies for controlling weeds include the ability to identify weeds as well as scouting fields on a regular basis to identify and solve weed problems as they arise. Spot spraying of herbaceous and woody perennials is a particularly good practice for controlling these weeds. Aside from no-till, conservation tillage techniques leave the option of light cultivation, such as shallow disking to eliminate weed problems. Often a combination of chemical and mechanical weed control combine for effective weed control. The benefit is decreased herbicide cost, on the other hand, the benefits of improved soil structure and organic matter is offset by increased cultivation. In the case of ridge till, herbicide use and costs can be drastically cut (Beck, 1997). Soil Moisture A crucial factor in the success of a conservation tillage program is selecting the appropriate tillage method and cropping sequence to match soil conditions and moisture. A crucial factor in the success of a conservation tillage program is selecting the appropriate tillage method and cropping sequence to match soil conditions and moisture. No-till in fact offers farmers more flexibility in arid conditions than does conventional tillage. A no-till system offers the advantage of increasing soil moisture through eliminating plowing. Most conventional practices in semi-arid prairies involve a cropfallow-crop cycle. However, with the added moisture in no-till, a rotation can be intensified. In addition stubble helps to capture and hold snow in a field, preventing it from drifting. As the snow melts, it is gradually absorbed into the ground adding to soil moisture (Beck, 1997). In areas of higher rainfall and soil moisture where a no-till system may be difficult to implement because of excessive soil moisture, conservation tillage practices such as ridge or strip tillage can help improve soil drainage and allow soil to heat up quicker, allowing plants an early start ahead of weeds. Integrated Pest Management Just as Integrated Pest Management forms an integral part of conventional systems, so does IPM form a part of conservation tillage systems. Crop rotation assumes greater importance in conservation tillage systems because there is an added element of residue that could play host to plant diseases in planting the same crop consecutively. While many conservation tillage systems plant the same crop consecutively, this is not always the wisest management practice. In many cases yields are higher for crops when they are 12

14 planted in rotation with other crops, rather than in to the same crop. Pest problems in conservation tillage practices are no greater than in conventional systems. However, there may be a shift in pest problems. Part of this may be due to residue left over from the previous season. This problem can be resolved in various ways. The simplest is a diverse crop rotation, whereby even if the pest is present in the residue, the process of planting a different crop the following season will deprive the pest of an adequate host. Another solution is to chop up residue thereby destroying and reducing the number of pests. Cover crops also are a viable option in certain circumstances due to the fact that they attract beneficial insects that serve as predators and parasitoids to pests. Selecting resistant varieties is strategy that can be used to reduce pest problems (Hill, 1996). Plant Diseases Will the presence of residue increase host agents for plant diseases and create a more humid and beneficial atmosphere in which plant diseases can thrive? This is a particular concern in areas where wheat is planted into the stubble of the previous harvest s wheat. If managed properly there should be no increase in the amount of plant diseases. This problem can be mitigated by using different varieties of wheat, selecting in specific for disease resistance. Whenever possible Crop rotation should play a role in decreasing the ability of residue from a prior harvest to contaminate the present crop. (Bailey, 1996 and Hill, 1996) Residue Management One of the main factors for determining a conservation tillage system s success is the maintenance of at least 30% crop residue on the surface. Ideally residue should be evenly spread and distributed over fields. Conservation tillage will reduce the amount of residue incorporation into the soil, keeping as much residue on the surface where it can help minimize soil and wind erosion. Problems can arise with residue. One of the most common problems is uneven spreading. The result are patches of residue causing wetter and colder conditions to exist than other parts of the field. Another result is ineffective herbicide contact with weeds and increased weed problems. Thick layers of residue may pose a challenge to tillage equipment. In some instances it may be necessary to thin out the amount of residue in order to ensure effective planting. (Hill, 1996) Soil Fertility Reducing and eliminating tillage helps increase soil fertility. Residue left on the soil not only serves in the capacity of soil conservation it also adds organic matter to the soil as it decomposes. In addition reduced plowing reduces the decomposition of organic soil matter. Soil fertility, tilth, and structure are improved by conservation tillage practices. Residue left on the surface decomposes adding organic matter to the soil. 13

15 Added organic material means an increased amount of carbon. Additional nitrogen needs to be added in the form of chemical fertilizer or leguminous crops in order to balance the carbon nitrogen ratio. Cover crops add organic matter to the soil as well as provide conservation benefits. Cover crops help to suppress weeds by allelopathy (such as with cover crops such as rye) or through competition with weeds. Cover crops also offer the advantage of adding organic matter (and in the case of legumes, nitrogen) to the soil, helping to decrease fertilizer costs. This is particularly important for the CIS where decreased subsidies have made chemical fertilizers prohibitively expensive. Erosion protection against wind and rain are an added advantage of cover crops. Excess water from heavy rainfall and waterlogged soils can be absorbed by cover crops. Environmental Effects Concerns have been raised about the increased use of herbicides and its potential for negative impact particularly on water systems. These concerns cannot be taken lightly. Herbicides such as atrazine, gramaxone, and 2-4D can have potentially negative consequences on the environment and humans if not applied judiciously. However, the problem is all relative to the proximity of agricultural land to the water table, and to streams. The low amount of rainfall received by semi-arid prairies makes the likelihood of contamination from runoff or infiltration of the water table unlikely. These concerns hold more weight in areas of high rainfall (Cameron and Oram, 1995). In many respects the added reside in conservation tillage helps to reduce and eliminate runoff that of agrochemicals. Herbicides such as glyphosate (round up) are the most benign to the environment. It rapidly decomposes and has little if no known negative side effects. The question of environmental contamination as a result of herbicide misuse should not be taken lightly, particularly in an area of the world where past use of agrochemicals was often excessive and irresponsible, often leading to negative environmental consequences. Economic results Although Conservation tillage was originally created and promoted for its ability to drastically reduce soil erosion it also has the added benefit of being equal to in cost or more economical than conventional tillage methods. The savings are realized in reduced fuel, labor, and machinery costs. Fewer trips on fields reduce fuel costs, which also translates into less time spent tilling, decreasing labor costs. Many farms have become self sufficient and no longer need to hire outside labor. Machinery experiences less time in use and therefore less wear and tear. Tractors can be smaller and often last much longer in conservation tillage systems than in conventional. However, costs vary from crop to crop, and from system to system. No one conservation tillage technique is the most economical or fitting for every situation. Profits are maximized when an appropriate conservation tillage technique is matched with the proper soil and cropping conditions. 14

16 All conservation tillage systems use less fuel than conventional tillage. However, savings differ as tillage is reduced. No-till saves the most fuel, while chisel plowing uses more fuel than other conservation tillage practices, it still saves more fuel than conventional tillage practices. On a 600 acre farm these savings would translate into fuel savings ranging from $720 in the use of chisel tillage, to a savings of $2,172 in no-till systems compared with conventional tillage (Hayes, 1984). Herbicide costs differ between different tillage systems. No-till uses the most herbicides out of all tillage systems, followed by conventional tillage. These two practices use the most herbicides because they apply herbicides to the whole field. Other conservation tillage systems such as ridge till and strip till reduce herbicide use by banding it to the areas where planting occurs. Farmers practicing ridge tillage have at times managed to cut $40/acre in herbicide costs through additional cultivation and cultural techniques for controlling weeds. (Cramer, 1991) It is often difficult to gauge and compare costs from different systems. However, various studies indicate that for the most part conservation tillage systems are as profitable and productive (and in some cases more so) than conventional tillage. This is without even considering long term productivity due to soil conservation. Accounting for these factors make conservation tillage even more economically attractive than conventional tillage systems. According to the Conservation Tillage Information Center investment in conservation tillage equipment for a 1,200 acre farm costs 50% less than investing in conventional tillage equipment. Expenses are as follows: Tractor ($80,000), soybean/grain drill ($20,000), corn planter ($25,000), and a sprayer ($15,000) (Cameron and Oram, 1995). The following tables offer a look at the economic savings that conservation tillage systems have to offer in terms of reduced fuel use as well as reduced amount of actual tillage time to prepare and plant crops. Table 3: Diesel fuel requirements for various tillage systems (gallons/acre) Operation Moldboard Chisel Disk Ridge No-till Plow Plow Plant Chop Stalks 0.55 Moldboard Plow 2.25 Chisel Plow 1.05 Fertilize, Knife Disk Disk Plant Cultivate (2) Spray 0.23(2) Total Source: Jasa,

17 Table 4: Comparative labor costs Advantages of Conservation Tillage Systems Hrs/acre Cost/acre ($4/hr) No-till Till Plant Rotary Strip Tillage Disk Tillage Rotary tillage Chisel tillage Conventional tillage Source: Hayes, 1984 The Conservation Tillage Information Center in West Lafayette, Indiana lists fourteen major benefits from implementing conservation tillage. These benefits are the following: Reduced labor requirements Time Savings Reduced machinery wear Fuel savings Better long term production Improved surface water quality Decreased erosion Higher soil moisture Improved water infiltration Decreased soil compaction Improved soil tilth More wildlife Reduced release of carbon gases Reduced air pollution Source: Conservation Tillage: A Checklist for U.S. Farmers, 1996 Out of all these benefits there are several that are most pertinent to the situation in the CIS. From a conservation stand point soil erosion is an immense problem. Soil problems such as erosion, compaction, and fertility can be resolved through conservation tillage. These are major problems for immediate and long term agricultural productivity in the CIS. Conservation tillage will result in decreased erosion through increased residue, which helps to reduce runoff and provides cover against wind erosion. Conservation tillage requires fewer trips over the soil. In many places in the CIS there is a narrow window period for planting. Often tractors must plant during muddy conditions. The result often adds to soil compaction, with heavy machinery travelling over wet soil. 16

18 However, conservation tillage can reduce compaction. Less time is needed to plant due to decreased tillage operations. At the same time smaller tractors can be used with conservation tillage equipment because there is no need to drag a plough through soil. Farms in the CIS need to increase efficiency in order to be profitable. Conservation tillage provides numerous economic benefits. Amongst them are reduced cost for machinery maintenance, as well as fuel savings from reduced tillage. Initial costs for purchasing equipment can be offset by these economic savings. Environmental benefits Conservation tillage offers numerous environmental benefits. Added crop residue and minimal tillage both provide the effect of drastically reducing agricultural runoff of soil and agrochemicals. The result is minimized impact on the water ecosystem. Case Studies Innovative Ridge Till The Thompson farm in Iowa offers an innovative option for ridge till in the CIS. The Thompson s farming practices are unique because of the near absence of herbicides and chemical fertilizers in their system. Alterations in their ridge till equipment allow them to incorporate manure into ridges. The ridge till system used on the Thompson farm has succeeded in virtually eliminating herbicide use, and decreasing fertilizer costs by adding manure and cover crops to the soil. Weed control is through a combination of factors. The process of Ridge tilling eliminates 70% of weed seeds by knocking the top layer of soil off the ridge in between rows. The second step in weed control is based on a five year crop rotation of corn-soybeansmeadow-meadow- meadow or a three year rotation of oats with a green manure-cornsoybean. Manure and sewer sludge is applied prior to planting of corn and soybeans. Rotary hoeing is performed twice a season to control weeds. Corn and soybean varieties are selected for fast and tall growing varieties, in order to out compete and shade weeds. In extreme cases where weeds cannot be controlled through mechanical and cultural practices herbicides are applied directly to hard weeds to kill such as thistle. An experiment was conducted on the Thompson farm to compare ridge till without herbicides, with herbicides, and a conventional till system without herbicides. The conventional system experienced the worst weed problems. Broadleaf weeds were a problem in the ridge till system with herbicides, while the ridge till system with no herbicides experienced slightly higher yields than the ridge till with herbicides. The Thompson s believe that the use of herbicides selects a narrow group of weeds that thrive on the conditions on land where the herbicides are being used. (Pesek et al. 1989) 17

19 The ridge till and organic system used by the Thompson s is an applicable model for areas in the CIS where ridge till is an appropriate system. There is almost no herbicide or chemical fertilizer use, both of which pose limiting economic factors to farmers in the CIS. At the same time there are many farms that have manure. However, the ridge till system is very different from tilling systems that farmers in the CIS are accustomed to. While weeds are not a problem on ridges, they are present in between them. To the eye of a conventional farmer a field under ridge till cultivation may appear to have a weed problem, while in reality the weeds do not pose a problem to the crops on the ridges. The system also requires a change in management practices. Farmers will need to be convinced of its effectiveness and trained in its use. Cover Cropping In Conservation Tillage Systems Rich Bennett of Napolean, Ohio has incorporated cover crops on his 650 acre (260 hectares) into his wheat, corn, and soybean rotation. The results are increased soil fertility, lower costs, as well as decreased chemical fertilizer, and herbicide use. Several weeks following the wheat harvest in July Rich Bennett lightly disks the soil to kill weeds. A cover crop of hairy vetch is planted in September. Directly after seeding the soil is lightly disked again to kill late emerging weeds and incorporate vetch into the soil. The vetch is allowed to grow until April, when it is sprayed with a quart of 2,4-D per acre (2.5 quarts/ha). Only a fifth of the recommended amount of nitrogen is applied to the corn, amounting to 30 pounds per acre of nitrogen is applied to the soil. Soil tests help to determine if additional nitrogen is needed. A combination of one light cultivation and cover crop of mulch help to suppress weeds. Following the corn harvest, corn stalks are chopped up and rye is planted as a winter cover crop. In the spring the rye is sprayed down with a pint of roundup per acre, amounting to one third the recommended amount. Herbicide costs amount to $6 per acre a fourth to a seventh of the cost of conventional systems. (Hofstetter, 1994) Conservation Tillage in the Ukraine In Ukraine, minimum tillage practices have centered around the Poltova oblast. Dr. Nikolai Shikula the head of Soil Science and Geology at the Ukraine Agricultural Academy has been working on minimum tillage practices and sustainable agricultural techniques for the past 17 years. Much of his work has been conducted at the Ordjonikidge collective farm in Poltava. The farm has 4000 ha of land and has been rated the best farm out of 500 farms with similar characteristics in Poltova oblast. Two types of reduced tillage practices are used. The first involves a form of a deep plow penetrates the soil up to 25cm helping to break the plow pan without inverting the soil. 18

20 The second method is a shallow plow that penetrates 5-6cm of the soil. According to Dr. Shikula approximately 5-6% of agricultural land in the CIS is under minimum tillage practices (10.5 to 11 million acres). Much of what is considered minimum-till in the Ukraine, would not qualify as conservation tillage practices in North America. However, these practices have helped to conserve soil while increasing yields (see table 2). Table 5: Yields from Ukrainian Minimum conservation methods Crop Increase in Yield (kg/ha) Total Yield (kg/ha) Winter wheat 102 6,050 Corn 680 7,290 Sugar beets 4,100 52,900 Source: Cameron and Oram, 1995 Monsanto has also been working with farmers in the Ukraine. Much of their work has focused on promoting no-till practices. Economic conditions put herbicides out of reach of most farms. In response to economic conditions Monsanto has bartered herbicides in exchange for a portion of wheat harvests. They have also provided nozzles for agricultural machinery to help reduce and optimize herbicide use on agricultural land. However, more systematic work on conservation tillage practices for specific conditions for Ukraine is required (Cameron and Oram, 1995). Russian Conservation Practices Russian estimates on minimum tillage practices in the CIS far exceed those made by Dr. Shikula in the Ukraine. According to Russian estimates from million ha of land has been under minimum tillage. Cereals, sugar beets, and potatoes have all been cultivated using conservation tillage. Most of the conservation tillage in Russia has focused on winter wheat. Tillage represent 35% of farm production costs. One of the noted advantages of conservation tillage has been a decrease in energy costs of up to 25% as a result of decreased tillage. Conservation tillage practices in Russia include a rotation between deep and shallow tillage to deal with heavy soils that are easily compacted. Wide tires are used to help to distribute the weight of tractors (Cameron and Oram, 1995). The Case of Moldova Moldova offers an interesting study on conservation tillage programs for the CIS. Despite its small size (3.4 million hectares of which 1.75 million ha of agricultural land in annual crops) Moldova s mild climate and fertile Chernozem soil helped make it a major agricultural producer for the Soviet Union. However, soil erosion is a problem in Moldova. Agricultural practices place little focus on soil conservation techniques, emphasizing production over conservation. Approximately 30% of agricultural lands are severely eroded and an estimated 25 million tons of topsoil is lost per year. 19

21 USAID implemented a conservation tillage project through their Environmental Policy and Technology Project (EPT). The project set up three experimental stations around Moldova, coinciding with the three regions of the country. One of the sites was on an experimental farm, while the other two were on cooperative farms. The chief agronomist from one of the cooperative farms and the farm manager from another cooperative farm were brought to the U.S. for a study tour, part of which focused on conservation tillage. They had the opportunity to meet with farmers and researchers working on conservation tillage, and most importantly to see how conservation tillage works. A variety of conservation tillage equipment was brought to Moldova allowing for different conservation tillage practices to fit different needs and circumstances. Scientists from the Institute of Soils, Biochemistry, and Soil Amelioration conducted in depth studies on the work done in conservation tillage in Moldova. Cultural considerations played a large role in selecting an appropriate conservation tillage practice. Farmers and policy makers in Moldova were reluctant to involve themselves in the project. During Soviet times agriculture was based on excessive use of agrochemicals. Many of the project participants had become aware of the negative consequences of such actions, and had a negative association with the herbicide and chemical fertilizer use. Another challenge was resistance from farmers to reduce tillage. The move to introduce no-till practices was met by resistance by local farmers, who were accustomed to fields free of stubble and residue. After careful analysis of farmers concerns the project chose chisel plow tillage as an ideal conservation tillage technique to introduce into Moldova. The use of chisel plowing offered the farmers a situation in which they felt more comfortable. Some tilling was performed, but adequate residue was left on the surface to control soil erosion. One of the cooperatives that was selected implemented conservation tillage on 735 ha and 250 ha on neighboring private farms. Fuel savings alone amounted to 60 to 70 percent, accounting for a $15,000 in savings. The second cooperative was slow to implement conservation tillage practices. Members of the cooperative were resistant to change. Cooperative members feared that the conservation tillage machinery was too large and heavy and would result in soil compaction. Another doubt was that the machinery would not create adequate seedbeds. However, after positive results with conservation tillage on the other cooperative, opposition subsided and conservation tillage practices were implemented there as well. Education has played a big role in promoting conservation tillage. Educational programs have been set up for farmers, students, and representatives from the agriculture, health, and environmental protection organizations. Tours were offered for the various sites where conservation tillage practices were implemented. Moldovan specialists were trained and assisted until they became comfortable with equipment use. Technical assistance was readily available to explain theory and practice. 20