Daryl Domitruk P. Ag.

Manitoba Zero Tillage Research Association

Brandon, Manitoba, Canada

Recently, many farmers in the northern great pairs have improved the efficiency of their operations by adopting zero-till technology such as direct seeding and burndown herbicides. This was evident at the 1994 Manitoba-North Dakota Zero Tillage Farmers Association workshop in Minot, North Dakota where the theme was "The Zero-Till Alternative". At that workshop the collective experience of several zero till farmers was used to show that, compared to conventional fanning, zero tillage is a more profitable and environmentally sound system. In response to this revelation even more farmers have rushed to purchase and adopt zero tillage technology.

Despite their use of zero tillage technology, many producers continue to restrict their concept of crop management, including cultural practices such as crop rotation, to the practices they used as conventional farmers. However, continued adherence to the concepts that carried conventional farming limits the benefits that can be realized from zero tillage. Ultimately there is an increased risk of failure. In the long run a successful zero tillage operation will be one in which moisture, time, labour and capital are used efficiently. Attaining this level of efficiency in zero till will require producers to do more than simply replace tillage with herbicides.

As the current theme "Farming for Maximum Efficiency" suggests, zero till is not just an alternative but a farming system unto itself As with any system there are opportunities to improve and become more efficient. However, these improvements cannot be obtained solely through the use of new technology. The benefits of new technology will be short lived if the same crops are seeded in the same way at the same time and treated with the same pesticide year after year. Biological systems such as pest populations have a way of rapidly adapting to changing environmental conditions. Producers should recognize that zero tillage changes the land in many ways, and, as a result, some of the cultural practices that were used prior to zero tillage are less effective in the new agroecosystem created by zero tillage.

Increased efficiency in a zero tillage agroecosystem is most likely to be achieved by maximizing the positive aspects of the system. It is even better if' in addition, the strengths of zero tillage can be used to remove potential obstacles to efficiency (see Beck and Doerr's "No-till Guidelines for the Arid and Semi-Arid Prairies"). In any case, if we are to increase efficiency we should consider cultural practices that reflect the physical and chemical condition of zero tilled soils and the nature of pest populations that inhabit them.

A good place to start is to consider the link between crop pests and crop rotations. A more diverse crop rotation that includes a variety of crop types changes the times at which crops are seeded, sprayed and harvested. Greater diversity makes more efficient use of the favourable moisture conditions present under zero tillage. A more diversified rotation also allows a more varied herbicide program to be used which can be an effective way to prevent the development of resistant weed biotypes and, thus, avoid one of the major obstacles to efficiency in zero tillage.

At present, there are few crops other than the cool season grasses such as wheat and barley, and the cool season broadleaf crops such as field pea and canola, that are adapted to conditions in the northern prairie and parkland. Analysis of the climate in this region suggests that, while we are on the fringe of the adaptation zone for warm season grasses such as corn and heat loving, cool season broadleaf crops such edible bean, they are potential crop options. Evidence of this is present in the pulse crop development program at the Saskatchewan Crop Development Centre. Among the reasons we should encourage the development of legume crops is the rising cost of nitrogen fertilizer and the reduction in transport subsidies for grain in Canada. Similarly, corn lines with increased cold tolerance and reduced heat requirements are being produced at the Research Centre in Brandon. We should strive to develop zero till methods of sowing and harvesting these crops at the same time that breeders are selecting for earlier maturity.

While it may be some time before new crop types are available, there are things we can do with currently available crops to gain efficiency. Winter wheat, sunflower and forage legumes are examples of crops that are adapted to the northern prairie and can be used to introduce greater diversity into zero till rotations. Again, strong breeding programs in Manitoba and Saskatchewan have raised the genetic potential of these crops. Winter wheat has been developed exclusively as a zero till crop on the prairie where it is the ultimate example of a diversified seeding date and optimised development cycle. Support for the registration of improved varieties is in the best interest of zero tillers. The use of perennial forage legumes on a short term basis has great potential for reducing weed populations, providing nitrogen and improving soil structure. Once again, the rising cost nitrogen fertilizer and the removal of transport subsidies, particularly in Manitoba, suggest that diversification toward a larger animal-forage crop base is warranted.

Workshops such as this demonstrate the abundance of new technology that is being made available for zero tillage. This technology should compliment rather than determine the management decisions made on your farm. If you let technology do the driving you will go where the technology you possess allows you to go and not necessarily were you want to go. Currently, this is difficult to prevent. For example, it would be wise to consider the trade-off between the labour saving practice of one-pass seeding/fertilizing and the effect that its horsepower requirements and soil disturbance have on fuel and herbicide inputs. It is certain that a high degree of soil disturbance consumes more fuel and encourages weed seeds to germinate. Nevertheless, many prairie growers have been willing to sacrifice soil disturbance in order to conduct one-pass seeding/fertilizing. Others insist that soil disturbance at seeding is necessary to warm the seed bed. The difficulty resides in the fact that we don't yet know the relative value of such trade-offs. Since everyone's labour and financial resources are different there is no "right" way of doing things. However, for zero tillers the trade-offs inherent in choosing a seeding system should be assessed in the context of maximizing the advantages that are offered by zero tillage.

Growers have had considerable success in matching herbicide technology to crop rotations. Unfortunately, this has resulted in an apparent total reliance on chemical forms of weed control. Without doubt chemical weed control will continue to be a part of any efficient pest management program. Indeed, there is a particular need for greater diversity in the chemistry available for weed control in broadleaf crops. However, total reliance on chemical weed control is not sustainable. Shifting weed spectrums, sometimes in favour of species that are not controlled by currently available chemistry, too few modes of action, and high herbicide costs make the development of integrated weed management programs necessary and sensible. Nevertheless, integrated pest management is rarely practiced. This again suggests that we have too often equated zero tillage with simply replacing tillage with herbicides. As with any technology, a herbicide program should be designed to compliment an overall pest management strategy that consists of various cultural practices suited to the crop and the region.

Using the systems approach that was loosely referred to above, the Manitoba Zero Tillage Research Association is attempting to increase the efficiency of the zero tillage system. We are investigating potential changes in management that, when supported by improved technology, will help farmers sustain the advantages inherent with zero till. The association was born in the fall of 1992 when several experienced zero till farmers got together with Ducks Unlimited Canada and the Government of Canada. The three groups expressed a desire to establish a research centre dedicated to soil conservation and habitat preservation. It was agreed that such a centre should be operated by producers themselves and that it should provide encouragement to farmers through investigations concerned with the practical aspects of soil conservation. The MZTRA research farm is more field scale than people are used to seeing at government and university establishments. This format is intended to provide us with an opportunity to develop management Systems using input costs that a farmer would be familiar with. Ducks Unlimited Canada covered the initial expense of purchasing the land (260 hectares or 640 acres) Operating funds have been provided by the Parkland Agricultural Research initiative, the Manitoba-North Dakota Zero Tillage Farmers Association, individual farmer members, the Canada-Manitoba Agreement on Agricultural Sustainability and Manitoba's Sustainable Development Innovations Fund. The corporate sector has donated much of the inputs. Of our total budget 18,17 and 65 percent has come from producer, corporate and government sources respectively.

The past year was our first full season of research on the MZTRA farm located 18 km (10 mi) north of Brandon, Manitoba. This season saw the establishment of a field layout and the purchase of equipment The research farm serves as a zero tillage in western Manitoba for government, industry and university researchers.

To see where we should go in zero till we should look at where we have been. What have the last few years, with their abundant moisture, said about zero till'? Essentially, these years have shown us that we have a system that performs well but requires better ways of managing disease and excessive crop residue. These present gaps in our ability are not the "down side" of zero tillage because the same can be said about conventional tillage. However, we have yet to address these challenges in the context of maximizing the advantages that come from zero tilling. That is our next challenge.