Agronomist Notes

In between bouts of typing fury on my Nuffield report, I’ve spent the past week putting herbicide and fertility programs together as well as some business budgeting for 2010. It looks like we finally have the opportunity to haul wheat but, ironically, with the snow melt there’s no way we can get at the bins. After five snowy months of winter I find myself hoping for some cold weather and frost. What kind of person am I?

In this week’s newsletter, we’ll discuss the benefits and weigh the risks of seeding barley into cold or frozen ground. Next, I’ll reveal an interesting way to create temporary tram lines for the sprayer each year to help improve yield, maturity and grain quality. Last, I’ll provide an educational piece on the effects of pH and temperature on sugar movement within the plant. As always, we’ll end with fundamental and technical grain market news. Have a great week.

Agronomy

Seeding barley early into cold or frozen soil insert barley plant emerging

In the push towards economies of scale, expanding farms have to cover more acres with less machinery. Unfortunately, there is only a 20-day seeding window before yields start to decline come mid-May which has forced producers to start seeding in mid to late April. Soils at this time of year tend to be less than 5 degrees Celsius or below zero or may even be frozen in some spots. However, the benefits of frost seeding may outweigh the risks. My crop of choice for early seeding into cold soil is barley. 

Barley will germinate at a soil temperature of 3 degrees Celsius. Wheat, oats, canola and peas require 4-5 degree soil temperatures before they germinate. It doesn’t sound like much, but it takes a significant amount of heat to increase soil temperature by one degree in early spring. Barley has a high energy content inside the seed that helps it maintain vigour under cold temperature stress. The limited root growth in cold soil forces the plant to rely heavily on its own stored energy before it begins to take up moisture and nutrients. No other crop combines low germination temperature with high stored energy potential. That’s what makes barley a good fit for seeding early into cold or frozen soils. 

You may think of peas as another option because they only require a soil temperature of 4 degrees and their large seeds are packed full of energy. However, if conditions make a turn for the worst, peas have a limited ability to compensate for a weak plant stand. You’ll end up with a poorer crop all season long, creating its own set of problems with weeds and yield reductions. Barley on the other hand can compensate nicely under a reduced plant stand by tillering more.

Another benefit of seeding barley early is its ability to tolerate heavy frosts. Now, a heavy frost of -3 to -5 degrees Celsius will turn the leaves black and they will die off, striking terror in your heart. However, barley has an amazing ability to compensate for the loss of its leaves through prolific tillering. Wheat doesn’t handle heavy frost as well and doesn’t have the same kind of potential to rebound by producing more tillers. Canola, well, I think we all know how well canola handles frost. More terror.

The worst case scenario for early seeded barley is getting an inch of rain soon after seeding or a wet snowfall that melts and then freezes in sub-zero temperatures. The crown and overall cell structure of the plant is compromised and reseeding is inevitable. The greatest risk of early seeding is the cost associated with reseeding. Let’s look at the numbers to see what we’re risking by seeding early.

Steve’s quick math

½ L/ac glyphosate: $2.00/ac
Spraying: $3.20/ac
Barley seed: $8.00/ac
Seed treatment: $4.10/ac
Planting: $17.00/ac

The total cost of re-seeding back to barley is $34.30 an acre. Now AFSC crop insurance pays $20.00 an acre in reseeding benefits should you choose to insure. Factoring in insurance benefits, you’re still $14.30 an acre in the red if you have to reseed. However, the loss would be more than offset by the yield gains in wheat and canola through earlier seeding. In the end, if you have a lot of acres to cover and you don’t mind taking the risk, seeding barley into cold or frozen soils may be worth it. Yield is rarely affected if not improved and both seeding and harvest windows are extended. SL

Temporary tramlines can improve maturity and grain quality

One of the draw backs from intensively managed cereal crops is the maturity and quality losses caused by sprayer wheel track damage. The first pass at herbicide timing will reduce maturity to some degree but it may not be visible at harvest. The effects may show up as higher moisture content from delayed maturity or reduced kernel weight from compaction. The second pass at fungicide timing is worse as the crop is physically damaged from wheel tracks. The effects can be seen with delayed maturity, late tillers, higher grain moisture content, green stems and leaves and thin kernels. Now, depending on the width of your sprayer, you are reducing maturity, yield and quality on four to six percent of your cereal crop each year. It is significant?

In the graph to the right, the yield loss in the sprayer tracks is anywhere from 80 to 100 percent. That’s significant! The other side of the equation is the five to ten day delay in maturity from late maturing plants inside or adjacent to the wheel tracks. The delay in maturity can often be the cause of malt barley rejection due to green kernels and reduced plumpness. In wheat, delayed maturity can lead to poor quality as harvest is pushed out into mid-September when it’s more susceptible to weathering. Let’s just take a quick look at the yield loss numbers from wheel track damage.

Steve’s quick math

6% of wheat field affected by sprayer tracks
60% yield loss in 6% of field
50 bu/ac × 6% × 60% = 1.8 bu/ac
1.8 bu/ac × $4.80/bu = $8.64/ac

6% of malt barley field affected by sprayer tracks
80% yield loss in 6% of field
70 bu/ac × 6% × 60% = 2.52 bu/ac
3.36 bu/ac × $3.80/bu = $9.57/ac

So, even with a 60% reduction in yield on 6% of the crop, we stand to lose $8 to $10 an acre from herbicide and fungicide applications. Factor in the cost of a malt barley rejection to feed and the monetary loss jumps dramatically to roughly $80 an acre. The solution to this problem is temporary tram lines or seasonal wheel tracks that a sprayer follows with each pass.   

Benefits of temporary tramlines:

• Improves malt barley quality through a reduction in green immature kernels.
• Increases maturity by 3 to 10 days.
• Increases harvestability through less green straw run through the combine.
• Reduces moisture content from late maturing plants in wheel tracks.
• Safer storage from uniform moisture content.
• Ability to work late in the evening safely with visible tramlines to guide you.

Temporary tramlines are put in place with the air drill by lifting specific openers that match the wheel spacing of the sprayer. Let’s say you have an 80 ft sprayer on 10 ft wheel centres and a 40 ft air drill on 12-inch spacing.  To create a proper tram line, you would lift the fifth opener from the end of the drill and seed back and forth. This would leave two empty runs 10-feet apart across the entire field for the sprayer to travel down. If you had 10-inch spacing, you would lift the sixth opener from the end to get your 10 ft centred wheel tracks.

I know we all envision sow thistle and wild oats filling the empty wheel tracks but consider these points: First, the action of multiple passes from the sprayer will help to physically damage the weeds. Secondly, the opener will be lifted out of the ground to eliminate unnecessary soil disturbance that normally triggers weed germination. Thirdly, you can continue to apply seed on the soil surface to create what are called fuzzy tramlines. Fuzzy tramlines simply allow seed to be broadcast by the seed tube on to the tramline. Some of the seeds will germinate but will remain small, weak and provide a touch of competition inside the wheel track. 

The second potential issue to address is the reduction in yield in the tramlines because your yield potential is effectively zero and not 20, 30 or 40% of the average. In this case the two rows on either side of the tramlines are able to capture more nutrients, sunlight and water to produce higher yields and make up for the lost potential in the tram lines.  

The use of temporary tram lines is most beneficial to those who apply a fungicide or insecticide at flag leaf or flowering when crop damage is most significant. Also, for once, the upfront cost of setting temporary tram lines is nothing if you have a sprayer to air drill ratio of 2:1, like a 40 ft drill and 80 ft sprayer. Plus, you won’t need RTK or autosteer in your sprayer. I think the benefits far outweigh the risks and provide a low cost strategy to help improve yield, maturity and grain quality in cereals. SL

Big roots and fruits are all in the sugar

One of the primary functions of green plant material is to manufacture sugars though photosynthesis. These sugars provide the energy or fuel to drive cell division and are transported throughout the plant via the phloem to root and leaf tips, buds and flowers. Now the flow of sugar out of the cell is regulated by pH and temperature. Any fluctuation in both pH and temperature can have an effect on root development and fruit production. Let’s start with pH.
Sugar movement out of the cell into the phloem is regulated by the pH inside the cell. There are two nutrients that have an effect on pH which are nitrogen and potassium. Nitrates act to lower the cell pH and cause a reduction of sugar flow into the phloem. The effect is a reduction in sugar or fuel to critical areas of cell division like root tips and reproductive areas like buds and flowers. Excessive nitrate levels can often be found in our crops unfortunately due to our nitrogen fertility programs. We apply all of our nitrogen needs at seeding which leads to excessive nitrate availability at a time the plant doesn’t need it. The result is a plant that builds vegetation at a time when it should be building roots.

In the case of potassium, it has a positive effect on pH. Potassium raises the pH inside the cell and increases the flow of sugars into the phloem to be distributed throughout the plant. Thankfully, the majority of our soils are high in potassium but I would certainly keep an eye on tissue samples to qualify that potassium is actually getting inside the plant. 

Temperature is the second main driver of sugar movement out of the cell. In fact, it’s the fluctuation in temperature that really drives sugar movement out of the cell. For example, hot days in the high twenties followed by cool nights in the high teens are ideal for sugar movement. This temperature fluctuation favours auxin http://en.wikipedia.org/wiki/Auxin production which creates a loading effect of sugar into the phloem. If day and night time temperatures are hot and above 30 degrees Celsius, this creates gibberellin http://en.wikipedia.org/wiki/Gibberellin dominance and can actually suck sugar out of the phloem. This will result in the sugars staying inside the vegetative cells without being transported to important areas like root and fruit development.

The majority of my plant tissue samples come back high to excessive in nitrogen when taken at the tillering stage. This has me concerned with the amount of energy or sugar we can transport to developing heads and roots. We may be sacrificing root and fruit development in cereal crops by applying all of our nitrogen needs at seeding. There are strategies like adding ESN or Agrotain to your nitrogen program which use polymers or urease enzymes to slow the release of nitrogen. That could help reduce the amount of available nitrogen and avoid excessive nitrate accumulation in the plant which lowers cellular pH and reduces sugar transport. We can’t do much for controlling temperatures but we can help reduce temperature of the soil by maintaining a thin residue cover to reflect light and heat. Soil temperatures can be reduced in the summer by ten degrees Celsius through proper residue cover. SL   

Diagram source: StollerUSA

Market News

Technical Analysis

Canola: May futures. The short and long term trend is down.
HRS Wheat: May futures. The long and short term trends are down.
Corn: May futures. The short and the long term trends are down. 
Soybeans: May futures. Short term and long term trends are down.
Canadian Dollar: March futures. Long and short term trends are up. Look for a technical correction downward.
US Dollar Index: June futures. Short term trend is up and the long term trend is down. Market is looking for direction.
Crude Oil: April futures. Long term and short term trends are up.

Ask the Agronomist

I’m planning to start inter-row seeding this year with my SeedMaster drill and I’m concerned about drill skew. I’ve been told that a drill will easily have 6 inches or more skew, worse on uneven or hilly land, which would move my openers right into last year’s straw.  Have you ever done any research with this as I would hate to cough up the money for RTK only to have it negated by drill skew! GL, Yorkton, SK

First, I’ve talked with a few SeedMaster owners who feel the Smart Hitch only works about 60% of the time. I’ve been told that’s because the paddle senses last year’s furrow and not last year’s stubble. SeedHawk would argue their “SBR” technology senses last year’s stubble so even if you heavy harrow, the SBR still senses last year’s stubble and keeps the openers between the rows a lot better than the Smart Hitch. So, in your case is the drill skewing or is the Smart Hitch not working as designed?

Second, I suspect in drills wider than 40 ft you’ll start to see a bit of skew with tyne openers. Disk openers hold the ground better than tynes and will help reduce skew. To further reduce skew, there are a few options from Trimble that guide both the implement and tractor. The TrueGuide by Trimble steers the tractor so the implement stays straight. The TrueTracker system steers the implement to keep it straight. See info in links below.   

TrueGuide: http://www.trimble.com/agriculture/aggps-trueguide.aspx?dtID=overview
TrueTracker: http://www.trimble.com/agriculture/truetracker.aspx?dtID=overview   

In the end, the amount of skew can vary so widely I can’t say for sure which drills do or don’t on what degree of slope. What I do know is that we may have to look at implement steering, especially as we move to wider drills. I think as more people move into inter-row seeding we’re going to learn a lot about drill skew and what the solutions are. Steve