D. ROURKE AND A. HARGRAVE

AG-QUEST, INC., MINTO, MANITOBA

ZERO TILLAGE - can you afford the alternative? An increasing number of farmers have looked seriously at this question. Comparing the cost of mechanical weed control to the cost of control without tillage (use of cultural practices and herbicides) is starting to receive very careful examination. Many farmers are finding reducing tillage can result in a better bottom line. During the last few years the cost balance has been tipping toward achieving higher profit using no tillage. The costs associated with tillage have gradually been increasing (increased fuel costs, increased labour costs, more expensive machinery replacement, increased cost of machinery maintenance and repair) while the cost of zero tillage has been falling (lower Roundup cost, greater knowledge to use Roundup more efficiently).

The question everyone asks is "If zero tillage is so good why isn't everyone doing it? The answer is quite simple. Zero tillage requires change, changes in attitudes, perception and knowledge. Well tilled trash free seedbeds used to be the mark of a good farmer and of course many excellent crops have and still can be produced using tillage, however times have and are changing. Conventional tillage has resulted in a great depletion of soil organic matter and erosion of our soil resources. The health of the soil can be measured by its organic matter content, tillage has reduced the health of our soils. In some cases our soils have lost a lot of their productive value. Tillage has increased salinization, reduced water holding capacity, helped deplete nutrient supplies and left us with soils with poor tilth which easily crust and have poor water infiltration.

Many soils can't stand much more tillage. Plus the cost of tillage is increasing so many farmers also can't stand much more tillage.

The Manitoba North Dakota Zero Tillage Farmers' Association is a dedicated group of farmers who have as their association objective "to preserve our agriculture soil resource for future generations by promoting a system of crop production which drastically reduces soil erosion and builds up organic matter". The ZeroTill Association was formally organized at a workshop in Minot, North Dakota on January 22, 1982. However many of its founding members had been zero tilling since the mid 1970's. Lack of effective seed drills, good straw and chaff spreaders as well as the much higher cost of Roundup in those early days put these pioneers to the test. Through dedicated trial and error these innovative farmers were able to develop a practical alternative to tillage. Today with a greater understanding of the practical requirements of farming without tillage plus greatly improved grain drills and chaff and straw spreaders plus the lower cost of Roundup plus better knowledge to increase herbicide consistency and effectiveness plus higher yields especially in dry years plus increased land value due to elimination of erosion, can you afford not to zero till?

Fortunately zero till makes sense and dollars. Zero till is a sure way to sustain and improve our soil and at the same time zero till can provide higher profits.

The Zero Till Association was formed with three goals in mind:

1. to facilitate the exchange of ideas;
2. to encourage zero tillage research;
3. to disseminate zero tillage information

To this end the Association sponsors a number of activities including a three day winter workshop, a one day summer field tour and the publication of a quarterly newsletter. The attendance of the 13th annual workshop which was held in Brandon Jan.30-Feb.1, 1991 was just over 500. Interest in zero till is growing.

The Association also recently published a 'Zero Tillage Production Manual' with the assistance of the Federal-Provincial 'Farming for Tomorrow Program" as well as the 'North American Wildlife Foundation' and 'Ducks Unlimited'. Since its release on Jan.31, 1991, more than 5000 copies have been distributed. While a second printing will be necessary, a few copies are still available through Manitoba Agriculture, PFRA or Lyle Samson, Executive Secretary, Zero Till Association office at 2012 Westfield Ave., Minot, N.D., 58701.

The Zero Till Production manual contains information from experienced zero till farmers and covers all aspects of zero tillage. It is a practical guide which is well worth reading.

Dr. Ed Vasey (NDSU-Fargo) says 'The Zero till manual is the best ag publication to come out for a long while.'

Mr. David Lumgair, experienced zero till farmer (Thornhill, Man.) says "It contains excellent information, a lot of things that I thought I was the only one who knew.'

Mr. Joe Breker, experienced zero till farmer (Havana, N.D.) says 'I wish the manual would have been available when I started to zero till.'

If you are interested in reduced tillage, the zero till manual will help to get you started right.

The Zero Till Association has also initiated a demonstration farm. With the financial assistance from the Farming for Tomorrow program, the Zero Till Association is developing and demonstrating the latest techniques and equipment for conservation tillage at the Conservation Tillage Productivity Centre at Minto, Manitoba. The Centre is run at Minto, Manitoba by David Rourke, a board member of the Association and director of Ag-Quest, Inc. an independent agricultural research station. The activities of the centre are geared toward farmers just starting or in the early years of zero till. The centre was designed to compliment the Farming for Tomorrow program, On-Farm Conservation Tillage Program being conducted by farmers throughout the province. The centre will highlight 5 areas important to conservation tillage. These areas will include:

1. importance of crop rotations in building a reliable low risk reduced tillage system;
2. the role of various tillage implements in conservation tillage;
3. practical options to direct seeding;
4. methods of fertilizing in a conservation tillage system, and
5. weed control in reduced tillage.

1. CROP ROTATIONS

The importance of crop rotations is often underestimated in development of a sound long term crop production plan. While it is less work to grow only 1 or 2 crops, increased crop diversity can be important to reducing the risk of developing crop production problems such as crop diseases like blackleg in canola and flame chlorosis or root rots in cereals. Including special crops in the rotation can enhance cash-flow and often increases net returns. The Conservation Tillage Productivity Centre is highlighting the importance of crop rotation in a demonstration examining the interactions between tillage and crop rotations.

The tillage treatment includes conservation tillage, minimum tillage as well as zero tillage. The rotations include rotations with 100% cereals, 75% cereals and 50% cereals.

The crop rotation x tillage trial was established in the spring of 1990. After only 2 crops, major differences are already beginning to show up. The tillage systems were defined as follows:

Zero till - one pass seed and fertilizer

Minimum till - one fall deep till plus one ass seed and fertilizer

Conservation till - two deep tills in fall and one cultivation in spring and one pass seed and fertilizer.

Figure 1 illustrates the importance rotation can have on the yield of wheat. Wheat yields averaged 8 bushels higher when wheat was grown in a 50% cereal rotation compared to a 100% cereal rotation. While each tillage system benefited from improved rotations, improved rotations enhanced the yield of zero tillage the most. Zero till wheat yields went from being lower than conventional till yields in the 100% cereal rotation to having higher wheat yields when used in the50% cereal rotation. Likewise (Table 1) net profits from wheat were also improved with the improved crop rotation.

Barley and mustard (Figures 2 & 3) showed similar yield improvement with improvements in rotations. Again the use of a favourable rotation with zero tillage resulted in the highest yields and highest net profits (Tables 2 & 3). Mustard generally had poor vigour in this trial in 1991. Hail damage plus fertilizer damage resulted in lower than expected yields. Flax, while only included in the 50% cereal rotation had the highest yield (Figure 4) and net profits (Table 4) when grown under zero tillage.

The price and cost assumptions are given in Table 5. Note that grain prices were based on the 15 year average price set by the Canada-Manitoba Crop Insurance Corporation under the GRIP (Gross Revenue Insurance Program). The prices were $4.15/bu for wheat, $2.17/bu for barley, $6.45/bu for mustard and $7.29/bu for flax.

As the project continues, more economic scenarios will be analyzed. Table 6 illustrates four economic scenarios based on the 1991 trial. It is based on a 1000 acre farm with four 250 acre fields. While these projections are based only on 1991 results, it shows a strong advantage to using zero tillage along with a 50% rotation. Also the results of the trial conducted at Minto is very similar to the results of trials conducted at Indian Head, Sask. by Dr. Guy LaFond. The Indian Head results were presented at the 1990 Zero Till Workshop and were based on 4 years of study.

Table 1. Crop rotation x tillage trial. Minto 1991.

Table 2. Crop rotation x tillage. Minto 1991.

Table 3. Crop rotation x tillage. Minto, 1991.

Table 4. Crop Rotation x tillage. Minto, 1991.

Table 5a. Machinery Costs.

Costs include fixed costs such as depreciation, investment costs, insurance and housing; and variable costs such as repairs, fuel, oil and grease. Costs were based on commercial equipment usage. Rates were extracted from the "Farm Machinery Custom and Rental Rate Guide 1991" publication by-Saskatchewan Agriculture and Food.

Tractor costs are included in the calculated cost of equipment.

Table 5b. Chemical Costs.

I. Herbicides.

II. Fertilizer.

11-52-0 $300.00/Tonne

46-0-0 225. 00/llbnne

Table 5c. Number of passes with each implement under different tillage systems.

Table 6. Effect of crop rotation x tillage on a "1000" acre farm.

Rotations: 100% cereals - wheat, wheat, wheat, barley

2. TILLAGE DEMONSTRATION

Conservation tillage, reduced tillage, direct seeding, 50% cover, 30% cover, paratill, wideblade, subsoil, zero till are all terms which have been devised to help describe tillage-systems. The Conservation Tillage Productivity Centre has initiated a tillage demonstration which will help sort out various tillage options available to us today.

The tillage demonstration site consisted of evaluating the growth and yield of barley sown on nine tillage treatments. The treatments consisted of various zero till and minimum till systems compared with conventional tillage. Table 7 defines the tillage systems as they were used in 1991.

Tillage systems which maintained standing stubble over winter generally had the highest yields (Figure 5). These included zero till one pass, minimum till and zero till Noble blade and minimum till one pass. Yields were lower with tillage systems which eliminated standing stubble in the fall; these included conventional tillage and minimum tillage fall deep till. The yield differences between zero till one pass and conventional tillage was approximately 8 bu/acre. Yields were also lower with zero till fall or spring band and zero till paraplow. The reasons for the lower yields with these treatments are not readily apparent, however seedbed quality may be a factor.

Economic analysis of the tillage trial as shown in Table 8. The costs of various tillage systems were very similar except for zero till paraplow and zero till with spring or fall banding. One pass zero till had a cost of $94.64/acre compared with $95.85/acre with conventional tillage. However due to the more favourable yields with one pass zero till, the overall profitability was $18.14/acre higher for zero till than for conventional till.

3. DIRECT SEEDING

Many conservation till farmers fear poor crop establishment due to interference of large amounts of chaff and straw with seeding equipment. Development over the last 10-15 years have shown that if crop residues are adequately spread at harvest time, crop establishment can actually be enhanced rather than hindered when tillage is reduced or eliminated.

Table 7. Definition of tillage systems used at Minto, 1991.

*All fertilizer was applied as a one pass seed/fertilizer operation. Banding was conducted only for its tillage effect.

A Concord 10" spacing air seeder was used for seeding/fertilizing the trial.

When crop residue is allowed to remain on the surface the developing seedlings are less susceptible to dry seedbeds, wind damage and soil crusting. The Conservation Tillage Productivity Centre is demonstrating various seeding options available to benefit from leaving crop residue on the surface.

During 1991, a drill demonstration trial was initiated. Flax was seeded at 30lbs/acre with 5 drills, directly into winter wheat stubble. The drills included a Bourgault air seeder (narrow opener with mounted packers), a Concord 10" spacing (with either an Anderson paired row openers, a 6 inch shovel or 8" shovels), a Concord 12" spacing (12" shovel), an Edwards 8-12 hoe press drill and Flexicoil 5000 air hoe press drill. While there were minor variations in crop establishment and yield, all of the drills gave satisfactory performance. Yields ranged from 29 to 34 bu/acre. Within the Concord drill line, the yields were extremely similar with the Concord 10 (6" shovel) yielding the highest (34.8 bu/acre) compared to the Concord 12 (12" shovel) at 32.9 bu/acre. The slightly

Table 8. Preliminary economic assessment. Tillage trial. Minto 1991.

*barley @ $2.17/bu.

lower yield with the Concord 12 (l2" shovel) may be attributed to slightly more bunching of crop residue with the machine. The wide sweeps combined with mounted harrows slightly reduced the normally high trash clearance features of the Concord design.

There have been many improvements in drill design and availability for direct seeding since zero tillage was first attempted. Many drills are now available which can operate effectively and without hassle in high residue situations.

4. FERTILIZER PLACEMENT

Efficient fertilizer use is important in achieving the maximum economic yield. A demonstration has been initiated which illustrates the various methods that are available to ensure efficient fertilizer use in a reduced tillage system.

An example of one of the fertilizer trials conducted at the centre is shown in Figure 6. Six methods of fertilizer placement were examined in this trial in1991. The treatments included:

Fall band banded on 7" spacing with 3/4" openers

Spring band banded on 7" spacing with 3/4" openers

Seed placed all N with the seed

Broadcast 30 kg/ha N with seed with remainder broadcast (34-0-0) immediately after seeding

Side band side band N 1" to side of seed

Spoke wheel 30 kg/ha N with seed with remainder injected (28-0-0) into soil 12" wide rows and 8" spacing

The rates used were based on 50%, 100% and 50% of the total N required - less soil N to achieve a total yield of 60 bu/acre of barley. The actual rates applied were 8, 53 and 92 kg/ha N, Urea (46-0-0) was applied except where otherwise stated and phosphate (11-52-0) was applied with the seed in all cases. Large differences can be noted between various methods, however as rates change the performance of the various methods can also change. Seed placed fertilizer was the best treatment at the intermediate fertilizer rate, however it was the lowest yielding treatment when used at the highest rate. The performance of broadcast nitrogen tended to improve as the rate of fertilizer was increased.

The correct or best method of fertilizer placement will depend on a number of factors including:

1. availability of equipment;
2. rate of fertilizer to be used;
3. cost of various sources of fertilizer;

1. manpower availability at peak seasons;
2. opportunity cost of fertilizer application especially at seeding vs efficiency - yield response of various fertilizer applications;
3. crop sensitivity to seed placed fertilizer as influenced by soil texture, moisture, pH and crop type, and
4. potential leaching or denitrification losses.

At the Minto location, the highest yields were obtained when the fertilizer was either fall banded, side banded or split applied with the seed and the remainder injected. However highest yield does not always equate to highest

profit. For instance while the seed placement treatment at the intermediate fertilizer did yield approximately -5 bushels less than the highest yielding treatments, the fertilizer rate used was 39 kg N/ha less (53 vs 92 kg/ha). During the next 2 years further studies will be conducted. The final results will be assessed for economic implications including cost of equipment, opportunity cost, fertilizer efficiency and crop yields.

5. WEED CONTROL

Cost effective dependable weed control is an important key in all crop production systems. With increasing machinery and fuel costs and reduced glyphosate costs, the balance is tipped in favour of using herbicides rather than tillage to control weeds. And of course with reduced tillage comes less susceptibility to erosion. The demonstrations are examining alternatives to cultivation for weed control in fall and in spring prior to crop emergence. The use of pre-emergent herbicides with limited incorporation is also being looked at. With the development of herbicide resistance, it will be important in the future to use herbicides from a wide range of herbicide families.

One of the weed control demonstrations conducted at Minto is on quackgrass control. Quackgrass is a cool season perennial, which thrives under a reduced tillage system. Minimum tillage systems seem to provide an ideal environment for this weed as there is enough tillage to help spread the rhizomes around the field but not enough tillage to control the weed. The use of glyphosate to control quackgrass in minimum tillage and zero tillage becomes imperative. In the case of zero tillage where the cost of glyphosate is already incorporated into the costs, quackgrass can very shortly turn from being an expensive weed control problem to becoming a minor problem. Various rates of glyphosate were applied in either the fall or spring. When quackgrass control was assessed in the wheat crop in June (figure 7) the quackgrass significantly suppressed by both fall or spring treatments and by all rates. However by fall, differences in quackgrass regrowth were very apparent (Figure 8). While both fall and spring glyphosate applications can provide excellent control of quackgrass, the fall of 1990 was a relatively poor year for controlling quackgrass, resulting in good initial suppression but a large amount of regrowth by fall. Generally when conditions are favourable for quackgrass control, rates as low as .5 1/ha with ammonium sulfateand surfactant can give excellent control. When conditions are unfavourable for top control, even 2 1/ha will not eliminate quackgrass.

Important points to note when planning a quackgrass control strategy are:

1. treat when conditions are favourable for uptake and translocation of the glyphosate;
2. controlling quackgrass in the fall will often allow for higher yield next year (figure 12). Despite better overall control spring treatments gave substantially lower yields due to greater interference of the quackgrass with the crop, ie increased soil moisture loss, delayed seeding, etc.;
3. use of high rates to overcome poor growing conditions may not be warranted;
4. various crop rotations to include the use of pre-harvest glyphosate in flax can improve the chances of achieving top control of quackgrass;
5. due to the annual application of glyphosate and lack of spreading rhizomes, quackgrass should be easily kept in check, but zero tillage without quackgrass control is just pasture. Don't le the quackgrass get away.
6. Quackgrass which has become sod bound may squire special measures such as use of tillage to compliment the effects of the herbicide or to activate the rhizome system so herbicide uptake will be enhanced.

Changing basic traditional farm practices such as tillage require considerable effort. On farm programs in addition to comprehensive education programs will be important keys to ensuring reduced tillage initiatives become a permanent part of our philosophy and landscape. The Conservation Tillage Productivity Centre has an important role to help educate and motivate farmers towards adopting economical soil conservation programs.

"AN IDEA IS NOT RESPONSIBLE FOR THE PEOPLE WHO BELIEVE IN IT."

The Conservation Tillage Productivity Centre along with efforts of people like Guy LaFond, Dwayne Beck and Jim Kinsella can help to demonstrate the principle" the idea", as well as the advantages and pitfalls of zero tillage. However it is up to individual farmers to learn, and modify these principles.

Time has never been better (good drills available - even available on a rental basis, lower glyphosate price, increased knowledge) for zero tillage to be an important key to the future of your farm and a key to the sustainability of agriculture for the future.

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