Our seeding unit is a Conserva Pac air seeder which is designed to separate the fertilizer placement from the seed placement in a totally double shoot system. It has a narrow 5/8 inch fertilizer opener which is mounted on a deep tillage trip assembly. The fertilizer depth is set by adjusting the height of the frame in relation to the ground, the same way you would adjust a deep tiller. To each shank assembly is attached a seed opener packer system that allows for each run to accurately and independently place and pack the seed above and to the side of the fertilizer on the shoulder of the fertilizer trench. The fertilizer is mechanically separated from seed by the action of the seeding boot which physically pushes dirt into the fertilizer trench. It is further sealed by the action of the packing wheel which packs dirt over the fertilizer and at the same time packs the seed in a sideways action into the shoulder trench created by the seed opener.

To this system we have added another component. For our principal N source we used use NH3. We are using a triple shoot system by we endeavour to place both dry and NH3 fertilizers in the fertilizer trench and at the same time position the seed above and to the side of the fertilizer. Our objective is to have this seed zone sufficiently removed to prevent fertilizer damage to the seed while giving the seedling the best possible access to the fertilizer.

There are several reasons why we have chosen to go with this method of fertilizing at the time of seeding. Al the reasons have an economic base, a key to survival in this day and age.

• A desire to have a minimum of between row disturbance to minimize weed pressure and conserve moisture.
• A desire to have a one pass system for the entire seeding and fertilizing operation.
• A desire to utilize the cheapest sources of fertilizer.
• A desire to minimize the costs of blending.
• A desire to minimize the volume of products handled.
• A desire to use the fertilizer most efficiently, that is to have the fertilizer strategically placed to provide the best possible uptake for the crop and at the same time be least beneficial to any weeds.
• A desire to have a fractured zone below the seedling to allow for rapid and deep root development.

• While the amount of product handled and the number of passes required to get the seed in the ground are the least possible, the physical effort required at the exact time of seeding is increased because you are doing all operations at once.
• The risk of seedling damage increases with the rate of N used and with the proximity to the fertilizer.
• The risk of damage to the seedling is different with the source of N used.
• The ability of my seeder to be able to place the NH3 in the bottom of the fertilizer trench.
• The risk of seedling damage in relation to placement is increased by the relative dryness of the soil and by the soil type.

In order to capitalize on the advantages posed in the preceding points and to minimize the risks we needed to look at things we could do to achieve this.

- With regards to product handle we have one truck designated to dry fertilizer and one designated to seed. Each truck has an auger with an attached hopper hitched to the truck immediately behind and below the tailgate. This allows us to back into the seeder tank without having to line the truck up with the auger since the auger is already hooker up. Utilizing existing farm augers saves expensive drill sill costs and allows us to fill our seeder tank with high speed 7 & 8 inch augers very efficiently. Since we pull a 1500 gal NH3 tank we can get 90+ acres from one fill which is acceptable and not too time consuming.

- Looking at the risk factors involved with side banding fertilizer we need to examine the characteristics of the different N sources.

Dry N will be more easily separated from the seed band at the time of seeding but as time progresses it will maintain its concentration longer and for this reason might be more risky to seedlings as they send their roots into the fertilizer band. Physical separation and distance of separation are the two factors needed to be considered in this situation. With NH3 the risk is earlier in that the NH3 moves quicker in the soil with the result being that it can damage the seed if it is allowed to gain quick access to the seed. With time NH3 will likely be less toxic since the band will larger.

- With further examination of the above graph it is apparent the time factor will be constant and therefore the only things that can be changed will be on the risk side. The variables there are the same as were listed above, soil type, moisture content of soil, type of fertilizer used and rate of fertilizer used.

• Since our soil is a black clay loam the risk involved with soil type is at low end of this risk factor.
• In looking at the moisture aspect, the fact that in our area we tend to have adequate moisture in most years and that in an undisturbed zero till environment moisture levels are always higher than conventional, we have placed ourselves in to the lower end of this risk factor.
• Since our seeder was tested and proven with the use of dry fertilizer we were not concerned with risks of fertilizer damage using dry.
• Using NH3 gives us some concern in that we want to prevent rapid access of the ammonia to the seed row.
• In examining one characteristic of NH3 it is evident it moves more easily and quickly in loose soils. Since our seeder physically closes the fertilizer trench with the action of the seed tube and then packs and seals the fertilizer in its own trench with the packing wheel, we felt our unit would significantly lower the risk of NH3 damage to the seed as compared to other types of openers.
• One area that caused additional concern was that the COLD FLOW NH3 was released 3 to 4 inches above the bottom of the fertilizer trench. Because of this we were concerned as to whether we were actually getting the NH3 to the bottom of the trench, or was some of it being deposited on the side of the trench. This past year Westco fertilizer did some tests on our fertilizer practices. They used a product that when sprinkled on the soil in a cut away of the seeding plain allows you to get a visual idea of the movement and entrapment of NH3 in the soil. In our situation the profile was something like this. From what we could see it appeared as though we were getting the NH3 to the bottom of the trench and that there was actually a sealing of the NH3 stopping significant entry to the seed row.
• John Harapiak, manager of Agronomic Services and Thom Wier the Westco Rep at Yorkton were particularly helpful in doing the tests and providing me with the overheads I have here. It is their expressed concern this information not be construed as their recommendation since their work is only an effort to catch up to what farmers are already doing. Their work may lead to a point where guide lines could be established but at this time is not the case.
• To continue with what I was saying the movement of NH3 seems to be upward in the fertilizer trench but appears to be sealed off from the seed row by the action of the packer wheel. If we can consistently maintain this separation I feel comfortable enough with our use of NH3 at seeding.
• Another factor that I believe comes into play in our seeding practice is that the moisture in the soil is at the highest level possible at seeding because of the zero till it is less toxic to the seed in our seeding program than in a conventional one.
• The last point to be addressed is rate. Since our system places the fertilizer in what I believe to be the most advantageous place. I believe the relative rates of fertilizer can be reduced to obtain the same results as other methods. This does not eliminate the risks caused by higher rates but does help to reduce it.

It is important to emphasize the environment the fertilizer opener works in and that in turn is created by the seed opener for the seed to be placed in to is the most important aspect that we deal with. We have found that straw and chaff management are paramount in helping our seeder to work smoothly and properly. We have also found fertilizing depth is as important as seeding depth. We have found if we fertilize too shallow we can cause seedling damage and if we fertilize too deeply we can destroy the firm shoulder profile we placed seed onto. In this case the benefits gained can be lost because of poor seed placement. Ground speed seems to be a factor in maintaining separation. We have found seeding the opposite direction to what was the case the years before helps to maintain a more uniform seed fertilizer relationship.

Since there is a higher potential risk with the use of NH3 we try to use seed with a high seed vigor.

In this past year we were not as happy with our crops as we were the two preceding years in which we used this method of seeding. During the course of the summer we often wondered is we had done things different could we have had a better crop. It is possible problems with slow emergence and development, which I believe were caused by the abnormally low temperatures, could have been made larger because of our fertilizing methods. For the most part it seemed to be a year where if you stayed even with other systems you probably had a lot to be thankful for. This proved to be the case. At harvest time we able to be be in the field as soon as others around us so it would appear maturity was not adversely affected. With regard to yield I initiated discussion with two local Ag Reps. They said, from their work in filling out yield reports for our GRIP program, that the yields on our farms were for the most part above average and that they were by and large equal to other top producers in our area. It is not my desire to be seen to be better than others yet at the same time I want to know if what I am doing measures up. It is this comparison that allows us to evaluate our performance.

There are some things I am extremely interested in. One of these is whether we can maintain or improve our yields and efficiencies if we go to a 12 inch row spacing. In this scenario the fertilizer burn risk is even higher. I am hoping there will be more research done in this area that includes a fertilizer program similar to mine. This would help me to make the decision with less risk.