1 Agriculture Canada, Experimental Farm, P.O. Box 1408, Vegreville, AB

2 Agriculture Canada, Research Station, P.O. Box 1030, Swift Current, SK

3 Alberta Agriculture, P.O. Box 1408, Vegreville, AB

Experiences in recent years have shown the NE Alberta remains subject to both wind and water erosion. Erosion events occur somewhere in NE Alberta every year. Public awareness of soil loss is heightened by wind erosion events, typically occurring during May when fields are worked intensively to prepared for seeding operations. However summer fallow fields may be subject to wind erosion at any time during the 21 month fallow period. Water erosion events are typically a result of intense summer storms. Cropped fields will generally resists water erosion by early July, however, prior to the establishment of root systems all cropped fields as well as all summer fallow fields are at risk. The effects of the problem can be minimized using conservation tillage or by reduction of summer-fallow (Zentner et al 1992). The adoption of conservation practices is dependent on short term economic benefits or the reduction of the financial risk (Crosson et al 1986).

Considerable research has been conducted on the agronomic and economic benefits of reduced tillage systems. Some of the agronomic/soils benefits include reduction in soil compaction, decreased rates of loss of soil organic matter, and increased yields (Dumanski et al 1986.). Potential economic benefits are a reduction in costs associated with machinery use, and labor (Zentner et al 1992).

The objective of this study is to compare crop productivity and short term economic performance and risk of four tillage management systems so as to determine their potential use by producers in various soil zones in north eastern Alberta.

Agronomic Considerations

The Alberta study sites are located in the Dark Brown soil zone at alliance, Black soil zone at Wainright and Hairy Hill, and Gray soil zone at Plamondon (the soil at this site was classified as Gleysol) , and Elk Point. Four tillage management systems (TS) were compared at each site.

The zero tillage (ZT) treatment consisted of removal of the grain at harvest, followed by chopping and spreading of residue with a flail mower. A fall herbicide appropriate for the weeds that were growing was then applied. In the spring a broad spectrum herbicide was applied if required.

Two conventional tillage systems were also included. Conventional tillage one (C1) consisted of harvesting the grain, and again chopping and spreading the residue with a flail mower. Three fall cultivations were done on one day, followed by a single pass with the cultivator approximately three weeks later. Spring work involved one pass with the cultivator. Conventional tillage two (C2) consisted of the same treatment as C1, except that only one pass with the cultivator as opposed to three, was done on the first fall tillage date.

The Minimum (MIN) tillage treatment consisted of the same treatment as the conventional tillage systems except that the only tillage treatment is one pass with the cultivator in the spring. As in the zero till treatment an appropriate fall herbicide is applied. Spring cultivation was done on the same dates as the seeding.

The first fall cultivation was done on the approximate following dates each years: Alliance Sept. 17, Wainright Sept. 18, Hairy Hill Sept. 11, Plamondon Sept. 13, and Elk Point Sept. 15. The second fall cultivation was done on the approximate following dates each year: Alliance Oct. 13, Wainright Oct. 9, Hairy Hill Oct 5, Plamondon Oct. 9, and Elk Point Oct. 8. Plots were harvested on the approximate following dates each year: Hairy Hill Aug. 13, Plamondon Aug. 13, Elk Point Aug. 17 , Wainright Aug. 18, and Alliance Aug. 17.

All conventional tillage was done with a vibrashank field cultivator, and all plots were seeded with a double disc zero till plot seeder. Plots were seeded to Leduc barley, on the approximate following dates each year: Alliance May 11, Wainright May 11, Hairy Hill May 10, Plamondon May 12, and Elk Point May 14. Spring cultivation was done on these same dates. Table 1 lists the herbicide treatments that were required at each site.

Economic Considerations

Economic performance of each of the TS was modeled for a farm unit of 640 ac to determine the most appropriate machinery size. Machinery operating costs were modeled for the most appropriate size of machinery to perform the farm operations in a timely manner. Production costs, net returns and net present value (NPV) were calculated for the four TS using a budgeting framework (Zentner and Campbell, 1988). The net return was defined as the income remaining after paying all the cash costs (seed, fertilizer, herbicide, fuel, oil, machine repair, crop insurance premiums, land taxes, utilities, and interest on operating capital), labor and depreciation on buildings and machinery. The NPV were calculated using a discount rate of 5%. The net present value recognizes that returns earned in the future are worth less than money earned today. Management requirements, income tax and land equity costs were considered similar over the different TS. Inputs and field operations were held at their 1992 cost levels (Alberta Agriculture, 1992, Saskatchewan Agriculture and Food, 1992). Each system was evaluated at three barley price levels, and with and without participation in the Canada/Alberta Crop Insurance Program. Crop insurance is an alternative method of risk aversion available to producers. Participation was assumed to be at the 70% yield coverage option, and the premiums are specific to the risk area where the sites are located (Alberta Hail and Crop Insurance, 1989).

For each of the five sites, annual net returns and NPV were compared between the TS using analysis of variance for a split plot design with years being the main plot and tillage being the subplot (SAS Institute Inc., 1990). Differences among treatment means were determined by Duncan’s Multiple Range Test (p=0.05) (Little and Hills, 1978). Riskiness of the tillage systems were analyzed using stochastic dominance analysis (Goh et al, 1989). The risk efficiency sets for each TS were established for risk neutral producers and for producers with low, medium, and high risk aversion levels as defined by Zentner et al (1992), and scaled to the appropriate farm size (Raskin and Cochran, 1986). Risk averse individuals are willing to give up some expected return (profit) in order to obtain a reduction in the profitability of a low or negative return. Risk neutral individuals sole objective is to maximize net returns regardless of the variability of profits.

Grain and straw yield of barley for the years 1988 to 1991 are presented in Table 3. Barley grain yield was on average higher with ZT compared to all other tillage systems at all five sites, significantly at the Wainright (compared too C1) and Plamondon (compared to C1 and MIN) sites. Compared to C1 the ZT treatment was on average 5.7% higher yielding averaged over the five sites and four years. Straw yields were on average 7.4% higher on average over the five sites and four years. Table 4.

Cash costs of production for ZT were on average 6.5% lower than C1 production costs averaged over five sites and four years. Costs for depreciation for machinery and buildings were on average 22.3% lower for ZT compared to C1 averaged over five sites and four years.

The cash costs may increase or decrease depending on the cost difference of substituting tillage and labor for herbicides used for weed control. The machine and building costs will decrease because of less tillage requirements for ZT as compared to C1.

Similar cost relationships exist for the five sites, to different magnitudes. The costs over the four tillage systems were generally highest for Plamondon and progressively less for Elk Point, Alliance, Wainwright and Hairy Hill.

Participate in the Canada/Alberta Crop Insurance Program reduced average annual net returns and NPV for all cropping systems. The reduction in the mean economic returns reflects the added annual insurance premium compared to the infrequency of payouts received from the insurance programs. Generally crop insurance participation reduces the variability associated with each system.

Over the price levels and tillage systems, Wainwright consistently performed the best with respect to annual net returns and NPV, following by Alliance, Hairy Hill, Plamondon and Elk Point.

When the probability distributions of net returns were compared for producers with different risk references at the five sites, and at the different price levels, the sets of risk tillage systems were relatively small. The ZT system without crop insurance was generally risk dominant. The price of barley has little effect on the performance of the producer.

The more risk average the individual , the more of a tendency that they will choose a system that includes more tillage (i.e. ZT to MIN to C2). The trend of moving to more tillage took place at the sites of Alliance which moved from ZT to C2, at Hairy and Wainwright the shift from ZT to MIN. Elk Point and Plamondon showed no shifts in tillage systems and stayed with zero-till at all price levels and at all aversion levels.

Results from 4 years of this study indicate that the implements of zero and minimum tillage are potentially feasble, both economically and agronomically, for barley producers in east-central Alberta.

REFERENCES

Alberta Agriculture. 1992. Farm Machinery Costs as a guide to custom rates 1992. Publ 9M, Alberta Agriculture, Edmonton, AB. 18 pp.

Alberta Hail and Crop Insurance Corporation. 1992. Premium Tables - 1992 Crop year, Risk Areas 9, 12, 14, 15, 16, Lacombe, AB. 5 pp.

Crosson, P., Hanthron, M. and Duffy, M., 1986. The economics of conservation tillage. In: M.A. Sprague and G.B. Triplett (Editors), No-Tillage and Surface Tillage Agriculture; the Tillage Revolution. Wiley, New York, pp. 409-436.

Doll, J.P. and Orazem, F., 1978. Production Economics: Theory with Applications. Grid Inc.., Columbus, OH, 406. pp.

Dumanski, J., Coote, D.R., Luciuk, G. and Lok, C., 1986. Soil conservation in Canada. J. Water Conserv., 41(4):204-210.

Goh, S., Shih, C.C., Cochrane, M.J. and Raskin, R., 1989. A generalized stochastic dominance program for the IBM PC. South J. Agric. Econom., 21(2):175-182.

Little, T.M. and Hills, F.J., 1978. Agriculture Experimentation - Design and Analysis. Wiley, New York, 350 pp.

Raskin, R. and Cochran, M.J., 1986. Interpretation and transformations of scale for the Pratt-Arrow absolute risk aversion coefficient: Implication for generalized stochastic dominance. West J. Agr. Econ. 11:204-210.

SAS Institute Inc., SAS/STAT user's guide, Version 6, Fourth Edition, Volume 1, Cary, N.C.: SAS Institute Inc.., 1989. 943 pp.

Saskatchewan Agriculture and Food. 1992. Farm machinery custom and rental rate guide 1992. Publ 4.5M, Saskatchewan Agriculture and Food, Regina, SK.

Zentner, R.P., Brandt, S.A., Kirkland, K.J., Campbell, C.A., Sonntag, G.J., 1992. Economics of rotation and tillage systems for the Dark Brown soil zone of the Canadian Prairies. Soil and Tillage Research. (24) pp 271-284..

Zentner, R.P., and Campbell, C.A. 1988. First 18 years of a long-term crop rotation study in southwestern Saskatchewan-yields, grain protein, and economic performance. Can. J. Plant Sci. (68) pp.1-22.

Zentner, R.P., Campbell, C.A., Bowren, K.E., Janzen, H.H., Tinline, R.D., Cutforth, H.W., Brandt, S.A., Lafond, G.P., and Townley-Smith, L., 1990. The long-term agronomic and economic efforts of crop rotations in western Canada. In:Proc. Soils and Crops Workshop. New Frontiers in Prairie Agriculture. University of Saskatchewan, Saskatoon, Sask. 22-23, February 1990. Pp 171-179.

Zentner, R.P., Sellers, F., Campbell, C.A., Handford, K.R., and McConkey, B.G. 1992. Economics of nitrogen fertilizer management for zero till continuous spring wheat in the Brown Soil zone. Can. J. Plant Sci. (In press).