We operate a 1600 acre grains and specialty crop enterprise in the heart of the Regina glacial lake basin. The heavy clay land is flat and stone-free. Despite the semi-arid climate, continuous cropping and minimum tillage have been practised in our operation for eighteen years. Today, we will address the topic of how we direct seed our crop rotations.
Our crop rotations are selected according to proven agronomic
practice subject to six major considerations specific to our farm
operation. The factors influencing our crop rotation planning
are: 1) profitability; 2) weed control and herbicide management;
3) soil moisture and fertility conditions; 4) residue management;
5) disease control; and 6) seed purity. Our presentation
discusses the planning which enters into our crop rotation
decision-making as well as emphasizing the practical elements of
equipment modifications for residue management in direct
seeding.
The first consideration in our crop rotation planning is profitability. Although we might like to include a specific crop in our rotation, if in any particular year, we expect that crop not to be relatively profitable with respect to alternative crops, then we may adjust the crop acreage accordingly for that year.
Profitability analysis is comprised of planning and information collection. We keep abreast of current cropping and marketing information through attending courses and seminars, visiting trade shows, and collecting reading material for our extensive farm library.
Financial information derived from the farm account records is
translated into costs of production for each crop type on a per
acre and per bushel basis. Direct input costs such as seed,
fertilizer and chemical are attributed to each specific crop
whereas indirect costs such as wages, insurance and utilities are
averaged over the whole farm. Building and equipment amortization
estimates are derived from Repair and Replacement Planning
Schedules in which we target a replacement year and an estimated
replacement value for each building and item of equipment. Having
a good handle on our costs of production for each crop puts us in
a good position to analyse projected market prices and determine
crop profitability.
Weed control and herbicide management are the second most important considerations in our crop rotation planning exercise. We are committed to an aggressive weed control strategy and have invested a considerable amount of time and money over the years reducing weed populations in our fields. As a result of our commitment to weed control over the years, we have been able to reduce fertilizer input costs while at the same time realizing increased crop yields thereby directly improving our farm's bottom line. Therefore, weed control and herbicide management take considerable priority in our crop rotation planning.
Information collection in the form of production history mapping is critical to the decision making process pertaining to crop rotation planning. Each year, Brent prepares production history maps recording seeding, fertilizing and spraying operations alongside yield evaluations and comments on the overall effectiveness of the production program for each crop and field. For example, seeding records include crop and variety, rate and depth of seeding, direction of travel and date as well as all pertinent details pertaining to any post-seeding operations. Spraying records include chemicals applied, dates, rates, specific areas sprayed and effectiveness of the weed control program. Records of specific weed populations are also maintained and used in crop rotation planning.
To prevent the development of herbicide resistant weed populations, our detailed chemical spraying records are used to plan for the rotation of crops and chemical family groups on a yearly basis. Some of the considerations pertinent to our crop rotation planning with respect to weed control and herbicide management are: i) utilizing crop rotations which spread out the seeding, spraying and harvest seasons over a sufficient length of time to accommodate less than ideal weather; ii) managing thistle growth through choosing crop rotations which provide more effective competition and chemical control (such as choosing to grow wheat instead of mustard in a field showing evidence of thistle growth); and iii) choosing crop rotations to effectively limit the development of uncontrollable weed growth ( such as not growing crops having poor broadleaf control two years in a row to limit the development of buckwheat infestations).
Crop rotation planning must reflect our commitment to an
aggressive weed control strategy. We maintain barrier strips
around each and every crop. We cultivate and/or mow the ditches
as allowed to prevent weed populations from spreading. We
maintain the yard weed-free through an investment of time and
effort behind the garden hoe. Small or problem weed patches are
hand rogued to ensure the cleanliness of our fields. The combine
is cleaned between crops and between fields to prevent the
spreading of volunteer grains or weeds between crops and fields.
With so much attention paid to the details of our weed control
strategy, crop rotation planning must also reflect a commitment
to weed control.
The third consideration in our crop rotation planning is soil moisture and fertility conditions. Although proven agronomic practice might suggest an ideal peas following canaryseed rotation to control disease carryover and replenish nitrogen reserves depleted by the canaryseed crop, such a rotation may not prove feasible for us in an excessively dry year due to poor subsoil moisture conditions. Similarly, in an excessively wet year, this rotation may not prove feasible due to the likelihood of slough development on the heavy clay land and the resulting pea crop losses from drowning-out.
Soil moisture and fertility analysis provides critical information in the crop rotation planning process. As a cost of production, soil testing accounts for less than a penny per bushel of production and has ensured that our fertilizer dollars have been spent on the proper balance of required nutrients. As well, fall soil testing has allowed us to analyse our nutrient requirements in October and thereby take advantage of direct savings of $20,000 over the past two years on fall purchased fertilizer over what we would have spent in the spring.
Soil moisture conditions and fertility can vary widely from
field to field, crop to crop, and year to year. In any given
year, for the production of six crops, we will analyse 17 fields
for moisture, nitrogen, and phosphorus and pH. Sulphur will also
be analysed for fields considering mustard or canola; and
micronutrients may be analysed if a nutrient deficiency is
suspected. The moisture and fertility information optimize our
crop rotation planning to effectively channel dollars spent and
ultimately save money. The soil analysis business also operates
as a service to other producers and effectively becomes an
information sharing forum on new crop varieties and seeding
trials and tribulations.
The fourth consideration in our crop rotation planning is optimization of residue carryover. Low residue carryover as a result of the production of low residue crops such as peas and flax grown in succession can lead to wind erosion concerns. On the other hand, too many successive high residue crops of wheat and canaryseed can lead to excessive residue buildup, resulting in direct seeding problems the following spring. In this section, we will discuss more of the practical aspects of how we actually seed our crop rotations.
We have been continuous cropping and direct seeding with minimum tillage for the past eighteen years, sixteen of those years with an air seeder. Fall deep banding of fertilizer was used for many years but was dropped from our practice in 1991 due to reduction in soil tilth quality, drying out of the soil bed in years of little snow cover and the costs associated with an additional operation. We now apply 100% of our fertilizer requirements during the seeding operation. While a conventional cultivator with shovels has been the chosen seeding implement over those years, we have utilized a tine harrow, an oscillating "crazy harrow" and a Brandt rotary harrow to close up the seed bed, level the soil clumps and spread the straw in our post-seeding operations. Prior to our 1995 purchase of a used John Deere 9500 combine, we were harvesting with a Gleaner L2.
Our 1994 harvest produced both a large quantity of grain and straw residue. In order to obtain the desired harvest capacity with the Gleaner combine, we cut the stubble as high as possible thereby not putting any excess straw through the combine. We realized that additional straw management would be necessary in order to prepare for the 1995 seeding operation, so we strip-swathed the standing stubble at right angles to the prevailing winds leaving a 3 foot wide strip between passes to act as a winter snow catch. Our spring wheat, durum wheat and canaryseed fields (shown in the slide) were subjected to this residue management procedure in 1994. In 1995, we seeded peas directly into this canaryseed stubble with our modified Bourgault air seeder.
Our seeding system consists of a 1994 Bourgault air tank for which we manufactured and retrofit a double shoot air delivery system to replace the original factory single shoot system. The air delivery piping splits immediately ahead of the single air fan with the aid of a home-built flow divider baffle. In addition, a "diverter" valve was built into the fertilizer air stream to allow for the introduction of any desired amount of "pop-up" fertilizer into the seed stream thereby permitting 100% of the fertilizer to be placed during the seeding operation without seedling damage in any crop.
This unit is coupled to a 1994 Bourgault 5 row floating hitch cultivator equipped with 10 inch shovels on eight inch centres and Farmland SB-2 splitter seed boots which place two 2" wide bands of seed on four inch centres. This configuration was purposely chosen because the two inch space between seed rows is an ideal location to side-band the bulk of applied fertilizer. As well, with maximum seedbed utilization by the desired crop, we feel the crop has a distinct advantage over later germinating weeds.
Two air packages were purchased and modified to fit the cultivator with a double shoot air delivery system thereby allowing the placement of 100% of the fertilizer during the seeding operation for ALL crops. The rear of the cultivator was retrofit with home-built in-line rotary harrow and ninety-six 13" diameter rubber-tired in-row packer wheels. The object of these modifications has been to reduce fuel and labour requirements and obtain true single-pass minimum tillage in our farm operation. Although the in-line rotary harrow/on-row packer combination works extremely well in moderate residue dry operating conditions, these conditions seldom occur throughout the entire seeding season, so major modifications are again scheduled for the harrows and packers, this winter.
Re-design of the mud scraper system between 1994 and 1995 improved the packer assembly's ability to accommodate our wet heavy clay soils but further re-design of the packer system will improve its performance under wet conditions.
All shanks have been fit with home-built ultra high molecular weight plastic liners on the front to help prevent our sticky clay soil from adhering to the shank and reducing flow around the shank. The cultivator with shovels on eight inch centres is capable of handling very difficult straw residue conditions and allows us to accomplish effective weed control during the seeding operation.
The extremely wet 1995 spring conditions permitted the utilization of our modified equipment for the direct seeding operation but necessitated the use of the Brandt rotary harrows because the cultivator-mounted harrows did not perform satisfactorily under the extremely wet conditions. This slide shows the quantity of durum straw residue in our 1995 seeded flax and the next slide shows the 1995 flax crop later in the season.
For the 1995 harvest, the Gleaner L2 combine was replaced with
a John Deere 9500 combine and the John Deere straw chopper rotor
was replaced with a Rodonno straw chopper rotor which has twice
as many cutting hammers and produces a wider, much finer spread
pattern. As well, the spreading fins on the John Deere chopper
were altered to further widen the chopper spread. We now have 95
to 100% spread capability in all crops. For the 1996 seeding
operation, residue management has hopefully been completed
entirely during the 1995 harvest operation as the increased
capacity of the John Deere 9500 combine allowed us to cut 8"
high. For the 1996 harvest, we hope to install a second cutter
bar on the 30 foot header to permit us to cut higher and harvest
faster while still maintaining stubble height at no more than 8
inches.
In addition to profitability, weed control and herbicide management, soil moisture and fertility conditions and residue management, the fifth factor we consider in our crop rotation planning is disease control. Uncontrolled disease outbreaks can lead to serious reductions in yield and grain quality.
While we have found that even rotating from spring wheat to
durum wheat on the same field will reduce disease carryover,
disease control was one of the prime reasons for the introduction
of specialty crops such as peas into our rotation. Tan spot,
sceptoria leaf and glume blotch have all been experienced in past
years on fields cropped to the same crop too many years in
succession. The introduction of specialty crops has all but
eliminated cereal disease carryover while at the same time
improving soil tilth. Today, we control disease by ensuring that
cereals are not grown on the same field more than two years in
succession and that oilseed and pulse crops are not grown more
than one year in succession.
Seed purity is also a consideration in our crop rotation
planning. Purity is maintained in our market grain production by
choosing crops for which chemical control is readily available to
eliminate the previous season's volunteer growth. Grain which is
grown for our own seed use is grown on land which has grown the
same grain and variety for at least two previous seasons. This
ensures continued varietal purity even in a continuous crop
environment.
Subject to proven agronomic practice, there are six additional
factors which we consider in our crop rotation planning: 1)
profitability, 2) weed control and herbicide management, 3) soil
moisture and fertility conditions, 4) residue management, 5)
disease control, and 6) seed purity. The two most important
reasons for developing a sustainable crop rotation are shown in
this last slide, our two sons, Kyle and Kelvin....
CROP ROTATION PLANNING
FACTORS TO CONSIDER:
PROVEN AGRONOMIC PRACTICE SUBJECT TO: