Precision farming (PF) or site specific management is simply implementing the right management practice at the right time in the right place in the field. This technique has grown in popularity the last few years largely because of the premise that it would increase profitability. However the technology used in PF has far outstretched our agronomic expertise.
In conventional agriculture, the producer seeks to apply uniform application rates across the field based on field averages. There is an underlying realization that most parts of the field are not managed optimally in most years. Over fertilization in some parts, under fertilization in others is the usual result.
PF techniques are administered in an attempt to meet individual crop requirements as inherent variations in the field occur. These variations may include differences in: soil type, nutrient supplying power, drainage capacity, topography, as well as many other unknown factors. Because most agricultural research has revolved around uniformity (that is, trying to take natural variability out of the equation), producers have few research results to assist them in making PF management decisions.
To fill this void in agronomic knowledge, a number of research projects within the Universities and agriculture institutions across the prairies have been initiated. As well, several producer/marketing groups projects have been implemented. An example of the latter currently in progress is the District 35 A.D.D. Board Precision Farming Project.
Our research site is located between Lashburn and Waseca, SK (approximately 40 km east of Lloydminster on Highway 16) on the SW-08-48-24-West of the 3rd meridian. Our cooperator is Todd Hope. We are concentrating our efforts on a 40-acre parcel of this quarter section. The field has been direct seeded since 1989 and we continue to utilize direct seeding techniques in our research.
The project was initiated in 1996 by the District 35 ADD board. Immediately, a number of the local farm suppliers joined the project with in-kind support. Both the board and the agricultural retailers felt the agronomics of PF required more research from a producer's perspective. Therefore, the project utilizes farm-scale implements wherever possible.
The only operation that could be classified as non-farm-scale is seeding. We use a 12-foot Conserva Pak plot seeder on 12-inch row spacing. Although it is a plot seeder in principle, it uses the same shank design and packing design as found on larger seeders. The benefit of the plot seeder was the four compartments for seed or fertilizer and an anhydrous tank to supply the bulk of our N requirements. This allows us to put seed into one compartment and individual fertilizers (12-51-0, 0-0-60, 21-0-0-24) into the other three compartments, providing ease and accuracy in altering N, P, K, and S. Our seeding operation involves an up and back pass providing a 24-foot wide plot.
Spraying is completed using a high clearance sprayer. Harvest operations are facilitated using 22-foot wide swather allowing us to swath out the center section of each plot and threshing is completed using a 2188 Case AFS combine.
The first year of this project was marred by a late June hailstorm and numerous growing pains surrounding the new equipment. For instance, for harvest 1996, our combine did not have GPS. We attempted to use PFRA's GPS, but we were unable to make the yield monitor recognize the GPS signal. As a result, our yield results were similar to those one would have obtained using a simple weigh wagon. We estimated that the accuracy of the yield monitor was between 5 to 7% of the weigh wagon once all calibrations were completed.
In 1997 we grew Harrington barley and Karma wheat on the 1996 canola stubble. The growing season was excellent until mid-July. Little precipitation, combined with very warm summer temperatures, caused some of our high input plots to suffer tremendously (Figures 1 and 2). However, the harvest operation went much smoother with the aid of a 2188 Case AFS combine, which was fully equipped with a yield monitor and GPS and DGPS receivers. We estimated an error of 3 to 5% between the yield monitor and the weigh wagon.
During the summer of 1997, the University of Saskatchewan completed a detailed topographic survey of the 40-acre parcel. In the fall, they returned with their punch truck to complete a detailed soil classification and soil sampling of the site. We are beginning to compile a database of information, which we feel will prove useful in disseminating the yield variations across the landscape.
Data compilation proved to be a much greater task than originally anticipated. The creation of management units based on topography faltered and we did not obtain the comparison of yields to landscape position and fertilizer applied as we had hoped. However, the use of the yield monitor did prove to be a useful tool in comparing fertility and seeding rate treatments. In 1997, we had a good response to P in both wheat and barley (Figures 1 and 2), but there was no advantage to applying 50 lbs. of P205. The higher rates of N proved to be yield reducing in both crops. This likely resulted from excellent growing conditions early in the growing season and poor moisture conditions at the time of grain filling. One yield response of note is the yield reduction caused by reducing the seeding rate in the CPS Karma wheat. Changing the seeding rates in the Harrington barley did not have any significant impact.
In the fall of 1998, SAF purchased copies of a precision farming program called SSToolbox. It is a high-end GIS software package, which runs using ARCVIEW 3.1 as its platform. This is the program we are presently using for our data compilation. Presently, our problem is finding the time to become familiar with this program and all that it can do (we do not have anyone fully dedicated to this project). As a result, the remainder of the 1997 and 1998 data will be presented at the Conference in February. Copies of the data will be available at that time.
Treatments:
Wheat
Fertilizer base rate- 60-25-10-10
Seeding base rate- 90 lbs/acre
Nitrogen rates- 30, 60 and 120 lbs/ac
Phosphorus- 0, 25 and 50 lbs/ac
Potassium- 0, 10 and 20 lbs/ac
Sulphur- 0, 10 and 20 lbs/ac
Copper- 1 1/2 lbs/ac applied as a foliar application
Zero fertilizer
Seeding rates- 45, 90 and 160 lbs/ac
Barley
Fertilizer base rate- 60-25-10-10
Seeding base rate- 75 lbs/ac
Fertilizer treatments were same as wheat.
Seeding rates- 38, 75 and 115 lbs/ac
Acknowledgments
Border Agro
Conserva Pak Seeding Systems
District 35 A.D.D. Board
Dow AgroSciences
Enviro-Test Agricultural Services
Kasun Agro
Lakeland Implements
Monsanto Canada Inc.
Philom Bios
Prairie Farm Rehabilitation Administration
Saskatchewan Soil Conservation Association
Saskatchewan Agriculture and Food
Saskatchewan Wheat Pool
Tiger Resources Technology Inc.
University of Saskatchewan