Agronomist Notes

Hello Reader

We are nearing the 85% complete mark for harvest and it continues to be a slow grind. Rain delays and parts runs are all too common. Knives, guards, lifters and reel fingers are hot commodities this fall if that tells you anything.

Yields continue to be all over the map with topography explaining much of the variability. The higher ground seems to be outperforming the lower areas and heavy rains in late May early June during crop establishment can be to blame.

This week we’ll take a look at the results of our nitrogen side dress toolbar in canola. Next, I’ll share the results of our narrow versus wide row spacing trials. I’ll finish with a new concept and design to move from variable rate to vertical rate technology.

 

 

Harvest Progress

(Calgary to Drumheller to Three Hills)
Crop     Complete   
Wheat:    75%
Barley:    90%
Canola:   85%
Peas:     100%

Side Dress Nitrogen Toolbar

Success in canola

In 2013 we started the first of our side dress nitrogen toolbar trials. We took the concept of side dressing nitrogen from the corn and cotton growers who have seen increases in N use efficiency over broadcast granular or surface applied liquid nitrogen. With CTF and RTK guidance, we thought we could easily coulter in nitrogen between the rows, even on 12-inch row spacing. See the toolbar in action here.  If we could reduce the risk of nitrogen immobilization from heavy residue and the need for rain to follow application, side dressing would have a better fit than streaming it on. Made sense, right?

Well, the results came back very positive this year in canola. We generated a 14% yield increase using the side dress method versus the streaming method. We applied 120 lbs N/ac using UAN on each trial and you can clearly see where we stopped and started on the yield map above. The14% yield increase worked out to a $75.50 per acre increase in revenue from side dressing for the same amount of applied nitrogen. The interesting part is that it rained 15mm, 2 days after application, which should have been more than enough to wash the streamed nitrogen into the already moist soil.

The details:

Variety: InVigor L252
Seeding date: May 15
Fertilizer: 60-30-0-20 sidebanded at seeding
Herbicide pre-seed: Chlomazone trial + glyphosate
Herbicide: 1.35 L/ac Liberty + 200 ml/ac Assure II
Fungicide: Lance 142 g/ac + Boron/Calcium
Stored soil moisture spring: 2 inches
Rainfall May-June: 5 inches
Rainfall July: zero
Rainfall Aug-Sept: 11 inches
Stored soil moisture fall: 10 inches
Total: 18 inches – 10 inches = 8 inches used
GDD: 1393

Canola
Nitrogen side dressed (120 N/ac) = 65 bu/ac or 1.5 T/ac
Nitrogen streamed (120 N/ac) = 57 bu/ac or 1.3 T/ac
Nitrogen streamed (70 N/ac) = 58 bu/ac or 1.32 T/ac

Notes

• With offset hitch, 30ft drill and 60ft side dress toolbar, we have a hard time lining up the coulters between the rows.
• In our trials, some rows were taller as the coulter injected nitrogen right beside the row while some coulters ran 10 inches away from the row.
• We need to move to 12-inch row spacing on the toolbar with a hydraulic hitch so we can inject nitrogen consistently between the rows.
• There is very little evidence of root pruning where the coulters ran.
• Soil closed behind the coulter well only to open up later on after the soil dried up in the top few inches.

There is no question in my mind that a side dress nitrogen toolbar is worth the investment. The FAST 8100 was $70,000 for a 60-foot toolbar on 24-inch spacing. Split applications of nitrogen work and the toolbar reduces the risk of requiring rainfall to make it work. Here’s a little Steve’s quick math on the ROI a toolbar brings over streaming on nitrogen even when it rains after application.

Steve’s quick math
Toolbar: $70,000
Revenue increase from toolbar: $75.50/ac
1,000 acres of canola x $75.50 = $75,500
ROI: 1 year

I understand that we’re not looking for one more thing to do in our already busy, condensed growing season. However, when you can match nitrogen use efficiency with proper timing and give yourself the ability to measure yield potential before you slap down $40 to $70 an acre in nitrogen, you have a winning combination. The icing on the cake is that it hasn’t reduced maturity in spite of 180 lbs of applied nitrogen.

To date, we have three of the four R’s down for nitrogen application. We have the right time, the right place and the right form. What we need to do now is figure out the right rate, which we intend to match using our GreenSeeker. From there the sky is the limit. To date, our nitrogen rates have been high but still economically viable when you spend $42 an acre more on side dressed UAN and still generate $75.50 in additional yield. We’ll fine-tune our nitrogen rates over time but for now, we have the ability to adjust our nitrogen rates base on yield potential and commodity prices. We’re back in the driver seat and I feel that side dressing nitrogen will give us the advantage we’re looking for. SL

Narrow versus wide rows in wheat

Different hemisphere, same result.

There is a worldwide debate on the yield difference between wide and narrow row spacing in wheat. Why is that? All the research seems to support narrow rows (5-7.5 inches) versus wide rows (10-12 inches). It makes sense that narrow rows could outperform wide because they make better use of nutrients, moisture and sunlight along with less competition within each row. However, two trials, two countries, two different hemispheres yield the exact same results.

Back in February I posted the trial results from Richard Konzag who farms near Mallala, South Australia. Richard compared a John Deere Conservapak on 12-inch spacing to a John Deere 1890 on 7.5-inch spacing using spring wheat. This year we decided to compare 6-inch versus 12-inch rows at our place using spring wheat. We have a 3-inch offset hitch so a quick down and back on the same pass with half the fertilizer and seed provided us with a 6-inch spacing trial with the same amount of product. Here are the results:

Richard Konzag, 12-inch tyne vs. 7.5-inch disk
Planting date: late April
Variety: Mace HRS wheat
Seeding rate: 90 kg/ha or 100 lbs/ac
Target: 200 plants/ M2
JD ConservaPak 12-inch = 306 heads/ M2
JD Disk 7.5-inch = 432 heads/ M2
Heads per M2 increased by 41% in disk system on 7.5-inch spacing
Yield Increase: 0%

Steve Larocque, 6-inch tyne vs.12-inch tyne Concord air drill
Planting date: May 19
Variety: Sadash SWSW
Seeding rate: 125 kg/ha or 140 lbs/ac
Target: 350 plants/ M2
Concord 12-inch spacing = 540 heads/ M2
Concord 6-inch spacing = 832 heads/ M2
Heads per M2 increased by 54% on 6-inch rows versus 12-inch rows
Yield* increase: 0% (110 bu/ac vs. 111 bu/ac)

* Yield was an average of two 6-inch row passes and the average of 4, 12-inch row passes on either side.

Here is a classic example of utilizing soil, moisture and sunlight more efficiently via narrow row spacing yet never realizing the yield potential that was built. Between the two trials and two countries, narrow rows generated an additional 40-54% more heads per acre yet they never added up to an increase in yield. Wow!

I’ve quizzed the research community and it is likely that the weather post tillering had a lot to do with the lost yield potential. We had no rain and hot weather (25-30C) after tillering, right up until soft dough stage when we received a total of 11 inches from soft dough until harvest. Could it be that on average we just don’t have the finishing weather to take advantage of the additional yield potential? I for one refuse to believe there is nothing we can do to remedy this situation.

In the end, and like many have experienced, there has been no difference in wheat yield between wide and narrow rows in our climate on dryland. It has me baffled that we can produce an additional 1.2 million heads per acre yet never generate an increase in yield from them. If hot and dry weather in July-August are the limiting factors than we have to start looking at products to reduce the impact of that stress. For now, it looks like wide rows will have to do until we can figure out how to turn those 1.2 million plants per acre into additional yield. SL

Advances in vertical rate technology

I know you’ve all heard of variable rate but how many have heard of vertical rate? Blast Agriculture from Australia are developing a deep rip shank that can apply up to 6 different liquids on 25 mm increments at ten different depths. Liquid Systems  is a perfect match for liquid delivery.

How would you like to place calcium in that sodic sub soil layer sitting at 4 to 6 inches or nitrogen down 12 inches to promote deeper rooting depths? Perhaps some mid to deep placement of phosphorus to increase availability when the surface layer dries out during grain fill? There are a number of options and potential to manage your soil vertically rather than horizontally. We all know the composition of nutrients, pH and soil texture can change dramatically at depth, so here is a tool that could do just that.

The image you see here shows the liquid outlets, which look like wings spaced every 75mm down to 300 mm deep. The wings are designed to prune old roots and create new channels in the soil profile to distribute liquids or granular fertilizer. Six different liquids can be placed at each depth providing a great opportunity to address sub soil constraints, which typically occur at different depths.

A few features of the opener:

• Adjustable depth Root Cutter - 600 wide.  This will also be able to discharge liquid out on either wing (see below for further explanation).
• Additional outlet down behind Shin Guard that can discharge a liquid right behind the Point for maximum depth placement.
• The large wing at the bottom will now be able to be placed at any depth along the rear edge. 

This is a very new concept and has not been brought to market yet. For our UK friends, I can see these openers on your oilseed rape drills that deep rip down to 12 inches providing some aeration and nutrition at specific depths depending on your strategy. In Western Canada, I can see these openers used to ameliorate sodic soils with a ripping action and the ability to place calcium sulphate at depth to help kick that troublesome sodium off the clay profile. SL