October 15, 2013

Agronomist Notes

Hello Reader

By now harvest is 99% complete and the combines and trucks have been replaced with heavy harrows, sprayers and floater trucks. Several folks are busy discing sprayer ruts and drowned out areas as well. It’s a race to get prepped for spring and buttoned up for winter. (Isn't that Western Canadian farming in an nutshell?)

Basis levels just widened on most grains last week and will likely remain wide for some time given the massive volumes of grain around. I started to look at pricing 2014 grain with fairly attractive levels for off combine movement next fall.

This week we’ll look at a new and gratifying study out of Harper Adams University comparing CTF to random traffic and low pressure tire systems. Next, I’ll give suggestions and tips on the use of Ethrel as a PGR in barley. Last, I’ve included a short study on which inputs provide the greatest yield gains in pea production from Indian Head Research Farm. We’ll finish with technical grain market news.

Have a great week.

Pictured above: Hauling out some of the season's bounty, October 11, 2013, near Morrin, AB. I sure do love the simplicity of loading from grain bags.

CTF vs. Random Traffic vs. Low Ground Pressure

Which system generates the highest yield?

When I dove into controlled traffic farming, I had the privilege of visiting over 20 CTF farms before I made the big plunge. I was able to see first hand the challenges and opportunities CTF brought and believed quite simply, it was the only way to go. Not everyone has that privilege and must rely on research instead.

In all the literature I’ve read about CTF, there has been no research on comparing farming systems from ‘ground zero’, as in, starting from virgin soil, or a type of equivalent. The only comparison studies available were performed on soils that were previously trafficked. However, a research team from Harper Adams University in Shropshire, England recently published long-term trial work that began differently. They deep ripped and plowed first to ‘wipe the slate clean’ and then compared random traffic to CTF to low ground pressure tire farming systems and introduced shallow tillage versus deep tillage versus no-tillage for good measure. Now we’re onto something!

The project started by normalizing the research site before setting up the trials. They prepped the site by installing sub-surface drainage, deep ripped twice down to 24 inches then finished with a moldboard plow. Then they used remote sensing to determine the most uniform area to set up trials inside the site to make sure the soil type was consistent as well.

Let me point out the exciting results. In year one, all three CTF treatments (shallow tillage, deep tillage, zero tillage) yielded the highest with an average 14% yield increase over random traffic and low ground pressure tire systems. The highest yielding treatment was the CTF, shallow tillage (4 inches deep) treatment at 8.3 T/ha or 123 bu/ac. The lowest yielding treatment was the random traffic, zero tillage treatment at 6.8 T/ha or 100 bu/ac. I repeat, the lowest yielding system was the random traffic zero-till system. The system we hang our hats on in Western Canada could be the lowest yielding system moving forward.

Since switching to CTF in 2010 we have harvested tremendous yields and I have yet to see a production risk in this system. Yes, CTF has its challenges but the benefits far outweigh the risks. The Harper Adams study confirms what I witnessed on those 20 or more farms I visited during my Nuffield studies. Random traffic and zero-till impacts yield negatively when compared to controlled traffic. Four years of CTF under our belt and we’re just kicking into second gear with its potential. SL

Read the Harper Adams study here.

Photo source: V. Larocque

Plant growth regulators in barley

Wise use & risky tools

I’ve been working with PGR’s in feed and malt barley production for the last four years. Out of frustration I started to use PGR’s because no matter what variety, fertility strategy or area I was in, applying nitrogen rates above 100 lbs/ac usually resulted in lodged barley and would void any gains we made through intensive agronomy. Even with the perceived risks of yield loss from PGR’s like Ethrel (ethephon) we decided to push ahead anyway. Four years, two PGR’s and various application rates and timing later I’ve come to some conclusions that will help allow malt and feed barley growers attain higher yields in our semi-arid climate.

First, the two PGR’s I’ve been working with are Ethrel (ethephon) and Cycocel Extra (chlormequat). Ethrel is registered on barley but Cycocel Extra is not. From experience, the Cycocel Extra alone is not enough to reduce height and lodging and requires a second PGR application like Ethrel to follow up. For this reason, I’m putting Cycocel Extra on the back burner in barley and focusing on Ethrel. Here are the take home lessons I’ve learned:

The label rate of Ethrel is 400 ml/ac, which is nuclear in my opinion and not suitable for our area. Perhaps under irrigation, heavy seeding rates, high nitrogen rates and a very lodge prone variety would I ever consider the 400 ml/ac rate.
I’ve used the 333 ml/ac, 300 ml/ac and 250 ml/ac rate of Ethrel on both feed and malt barley. The 300-333 ml/ac rate will shorten crop height and reduce lodging but will open up the canopy and encourage late tillering. Rainfall, sunlight and an open canopy encourage late tillering.
I’ve had success with the 250 ml/ac rate of Ethrel which reduces lodging but doesn’t shorten crop height much and allow sunlight into the canopy. Late tillering is less likely with the 250 ml/ac rate so more suitable to a malt barley scenario.
In almost all cases, a PGR like Ethrel leads to a decrease in protein. The PGR improves nitrogen use efficiency so the added nitrogen goes into yield not protein.
The areas I would be very cautious using Ethrel are those that have temperatures in high 20’s and low 30’s in late June-July with windy days. Hot temperature, windy days can be very stressful to barley after an application of Ethrel. The active ingredient, ethephon, increases the resistance of water flow through plant tissue, so a hot, windy day with high crop water demand can stress plants and reduce yield.
Ethrel requires 7 days to become activated in the plant and is not effective at reducing lodging before this time period. Ethrel also acts as a PGR by releasing ethylene in the plant tissues, which reduces cell elongation and crop height.
Ethrel will delay heading by 3 to 5 days depending on temperature and application rate. Cooler days with high application rates can delay head emergence up to 5 days in my experience. Sounds bad but a lodged crop will take even longer to mature.
The timing of the Ethrel is absolutely critical for the PGR to be effective and not cause crop injury. Apply Ethrel at late flag leaf or just prior to awn emergence. You want the main stem and the tillers to be in full flag leaf stage. Application before flag can kill off tillers, application at awn emergence will reduce kernel numbers

There is always risk when applying growth regulators at the wrong stage under the wrong conditions. By adjusting our rates over time, I think we’ve fine-tuned what works in our area and understanding the risk, Ethrel is a good tool to help prevent lodging. Even better the price point is roughly $4.00 to $6.00 an acre. The biggest challenge with using PGR’s like Ethrel is the ability to do it on scale. Timing is critical and you really have to evaluate whether you can hit every field at late flag leaf, just prior to awn emergence. Another difficulty is product availability as limited retailers carry Ethrel outside of the irrigation district. If you’re thinking about using a PGR like Ethrel, understand the risks, proceed with caution, but realize that it could be a valuable tool in your quest for higher barley yields. SL

Research on ethephon here, here and here.

Photo: S. Larocque

Intensive pea production

Which inputs give the greatest returns?

As part of my intensive pea production strategy I typically use a few staples in my agronomy program. I start with plant densities around 10 ft2, add double inoculant (especially on virgin pea ground), top dress nitrogen when nodulation is weak and apply a fungicide. And after the 15% yield bump in trials this year, I may look at trying more chlormequat as a growth regulator at first flower. Now, this program is fine when you’re hitting 60-85 bu/ac at $7 to $8/bu for a total of $450-$500/ac and a net margin of roughly $200/ac. But what happens when margins drop by half or more? Which inputs provide the best returns on investment?

Chris Holzapfel from Indian Head Research Farm in Saskatchewan put together an interesting study that looked at which individual inputs contributed most to pea yields. The results were both logical and surprising. The top three inputs that provided the greatest yield increase were granular inoculant, foliar fungicide and increased seeding rate. What’s surprising is that the addition of a seed treatment and starter fertilizer did not result in a significant yield increase. In fact, the highest yield was achieved when starter fertilizer was pulled from the full input package.

The research is from one year’s data at a location 700 km from my client base. What’s interesting, though, is that I’m finding similar results in my own trials. We rarely add starter fertilizer, we double inoculate and we apply a fungicide at the start of flower. If you have 50 bu+ pea yield potential, perhaps you should look at adding or subtracting some of the inputs I’ve mentioned in your agronomy program next year. It might be that little tweak to push yields higher. SL

Source

Photo: S. Larocque

Top dressing UAN in yellow peas

In 2013, I was called to investigate a field of CDC Meadow yellow field peas that looked short, stunned and pale yellow. It was clear that nodulation was poor and I soon found out the producer had cut his granular inoculant rate in half after over applying it on the first tank. You could see a thick, tall, lush crop on the outside rounds and part of the east side. The other 200 acres inside the 320 acre field was pale and thin. The crop stage was 10 nodes and just about to begin flowering. The only option at that point was to apply nitrogen.

The producer bought John Deere streamer nozzles and applied 30 lbs/N/ac (UAN) with the sprayer. Come harvest time, the difference between the thick, lush crop with double inoculant on the outside round and the 200 acres inside was minor. The field ended up yielding 78 bu/ac, which is incredible considering it’s start and compares to neighboring pea yields.

The moral of this story is pea crops that suffer from poor nodulation due to short term flooding or acid soils or an oops with the inoculant rate can respond very well to liquid nitrogen in-season. You don’t want to go too heavy on the nitrogen and create a vegetative response. You also have to factor in nitrogen tie-up and volatilization but an application somewhere around 30 lbs/ac of actual N can turn a pea crop around. In this case, the $21.00/ac was money well spent. SL