Agronomist Notes

We’ve had a great run of weather over the past seven days and most producers just about have seeding wrapped up. Mitch and I finished Tuesday and we’ll immediately start some post-seed spraying. Germination and emergence on all crops has been incredible so far. I’ve heard of wheat germinating within 24 hours and canola emerging within eight days of planting. Buckle your seat belt folks! If this weather keeps up spraying season will be quickly upon us and it’ll be easily to lose crop staging if we’re not on the ball. That means I’ll be weed scouting, crop staging, and scratching in the dirt for emergence counts and drill/opener assessments.

In this week’s issue of Beyond Agronomy News, I’ll start by looking at how to improve the probability of response to foliar micronutrients. Next, I’ll provide you with some interesting research on the effects of cattle grazing on wheat yield from increased soil compaction. I’ll also give a quick run down on wireworm monitoring and control. We’ll finish with fundamental and technical grain market news.

Crop Staging Area (Calgary to Drumheller to Three Hills)

Seeded	April 23 - 31	May 1 - 7	May 8 - 15
Wheat	3 leaf 1 tiller	2 leaf	1 leaf
Canola	2 leaf	1 leaf	Cotyledon
Barley	3 leaf 1 tiller	2 leaf	1 leaf
Peas	4th node	3th node	2nd node

Agronomy

Steve’s tips for the week

• Watch for wireworm and flea beetle pressure.
• Get the sprayer ready to roll because in-crop herbicide season will come and go really quickly with warm soil temperatures.
• Start measuring emergence numbers in wheel tracks vs. outside wheel tracks. Are you loosing plants to compaction with your current air drill and 4WD?
• Monitor winter wheat if you had recent heavy rains. Yesterday I recommended broadcasting nitrogen on 900 acres after some heavy rain caused nitrate leaching in the past two weeks on sandy soil. 

Predicting responses to foliar micronutrients this spring

As we move into herbicide season, many producers will be thinking about applying foliar nutrients with their herbicides. In order to increase the probability of seeing a response, we need to understand what nutrients are needed the most at certain growth stages and what factors reduce nutrient availablity. Most people have had very little luck with foliars because they don’t measure the response. Measuring yield responses visually only works under severly deficient situations. Typically, a foliar may only provide a yield response of a few bushels which is impossible to see with the naked eye. 

To improve the chance of seeing an economic response from foliar micronutrients, I’ve organized a few charts to outline three things: 1) plant hormone cycles and nutrient requirements at certain growth stages, 2) levels of crop response to nutrients, and 3) physical and environmentally induced nutrient deficiencies. These charts will help you develop a checklist to see which nutrients are at risk of being deficient and the chances of seeing a response.

We are now half way through Stage I in Chart 1 where the hormone cytokinin begins to drop off after germination and auxin begins to form, a key hormone in root development. In order to develop strong, healthy new roots a plant must have a steady supply of auxin. Auxin is a key component in cell division and can only be produced in new leaves.

Chart 1: Plant hormone and nutrient cycles

The nutrients required to maximize auxin levels are calcium, phosphorus, potassium, zinc and manganese. For example, calcium acts like a tour guide for many nutrients and hormones. Calcium helps transfer auxin from the growing leaves to the root tips. Manganese, like calcium is another nutrient that helps transfer nutrients and regulates auxin levels. Deficiencies of any one of these nutrients can reduce cell division and ultimately, yield.

Chart 2: Crop response to nutrients

Crop	B	Cu	Mn	Zn	Ca	Mo	Fe
Alfalfa	High	High	Low	Med	Med	High	Med
Barley	Low	High	High	High	Med	Med	High
Canola	High	Med	Low	Med	High	Med	Low
Flax	Low	Low	Low	High	Med	Low	Low
Lentil	High	Med	Low	Med	High	High	Low
Oat	Low	High	High	Med	Med	Med	Med
Pea	High	Med	High	Med	Med	High	Med
Rye	Low	Low	Low	Med	Med	Med	Med
Wheat	Low	High	High	Med	Med	Med	Med

Source: Stoller Canada

Now that we know which nutrients are most critical at this growth stage from Chart 1, we can start to look at which crops respond best to specific micronutrients. For example, Mn, Mg, Ca and Zn are critical at the beginning of germination and establishment. Looking at Chart 2, barley responds well to Mn and Zn. Wheat responds well to Mn and canola responds well to Ca. With this information we can look at the environmental and physical conditions that may induce a deficiency with these micronutrients. 

Chart 3. Physically and environmentally induced nutrient deficiencies

Let’s bring it all together with an example. It’s May 30th and soils are warm and moist. Soil pH is high at 7.8 and the wheat is at the three leaf stage. Organic matter levels across the farm are between 4% and 6%. Soil and tissue tests reveal marginal levels of manganese, magnesium and phosphorus. If we look at the charts we know that: 

• We are now at the beginning of Stage I where calcium, zinc, manganese and molybdenum are required the most to maximize cytokinin and auxin production.
• We know that wheat is highly responsive to manganese.
• We know that high pH’s can induce manganese deficiencies.
• We know that high organic matter can cause manganese deficiencies.
• There may be some areas with sandy textured soil that may cause manganese deficiencies.

Based on this knowledge, we can predict that manganese may offer us the greatest probability of a response. The next part of the equation is the cost. The cost of a foliar chelated manganese product is roughly $6.00 to $8.00 an acre plus $3.00 application with your own sprayer. To run a proper analysis on the potential return on investment, let’s run the numbers.

Steve’s quick math

Mn foliar plus application is $11.00/ac. CWB PRO No. 1 wheat is $4.60/bu
3:1 ROI: $11.00 x 3 = $33.00
$33.00/ac ÷ $4.60 bu = 7.17 bu/ac
7.17 bu/ac ÷ 50 bu/ac average = 14% yield increase  

Therefore, you would need a 14% increase in yield to provide a 3:1 return on your foliar manganese investment. If you subtract the cost of the spray application because you were already going over the field with an herbicide, you would need a 10% yield increase to generate a 3:1 return.

The reality is, those who stand to see the quickest pay back on any foliar micronutrient program are those who are trying to push yield and achieve over 70 bu/ac wheat, 100 bu/ac barley and 60 bu/ac canola. If you start focusing on the charts I’ve listed above, you can begin to understand what nutrients are needed the most at which growth stages, which respond the best to certain nutrients and what physical or environmental conditions may increase the chance of seeing an economic response. From there we can dive into the right product, the right rate and the right time but that’s another article. SL

NutriAg: http://www.nutriag.com/products/index.htm
Stoller: http://www.stollercanada.com/products/liquids.html
Omex: http://www.omex.com/agriculture/ProductsList.aspx?cat=20

Should you be concerned about soil compaction from grazing livestock?

Everybody will tell you that livestock causes some level of compaction in the soil. Unfortunately, nobody knows how much and what kind of yield loss one could expect from grazing cattle on stubble. I was recently sent an interesting study from Australia on the subject. 

Table 1 displays the reduction in wheat yield from the check from compaction caused by livestock at five locations. From this study, soil compaction from livestock would result in yield losses less than 10 percent on average. Under very wet conditions yield losses were as high as 15 percent.

Summary of compaction research results:

• Livestock apply similar pressures on the soil to unloaded vehicles
• Livestock tread marks reduce soil porosity, water infiltration rate and increase soil bulk density and soil strength, although the effects are mainly in the top two to four inches.
• On average, even the most severe cases of soil compaction by livestock a 15 percent yield reduction could occur.
• Maintaining and building soil organic matter will help reduce the effects of compaction as organic matter acts like a sponge and bounces back quickly.  
• Compaction from livestock is shallow and not long lasting so the effects can be alleviated through natural wet-dry cycles or other natural processes.

So for those of you who run cattle on stubble after harvest, it looks like you’re potentially loosing very little yield to compaction, especially with our winter freeze-thaw cycle. If livestock are compacting soil within the top four inches, then our freeze-thaw cycle should be more than adequate to remove it by spring. Also, our soils are rich in organic matter from 3 to 6 percent which provides a sponge to help the soil bounce back to its natural state. If you want to throw numbers at it, I believe the added value from nutrients contained in manure and urine can more than offset the potential reduction in yield caused by grazing cattle.

Source: Dr. Lindsay Bell, Southern Queensland Farming Systems, CSIRO

Now is the time to look for wireworm damage

Now is the time to begin scouting fields with histories of wireworm damage. Wireworms can spend roughly four years of their life cycle as larvae in the soil. They prefer cool, moist soil and tend to be active in the top six inches of the soil. Early in the growing season, they are attracted to the carbon dioxide produced in the germination process and will come to the surface to feed on emerging plants. This is the time when they will cause the most damage to crops, usually by shredding below ground plant tissue.

Description

Wireworms are slender, cylindrical, hard-bodied insect larvae reaching up to 4 cm (1 1/2in.) in size. They are usually copper-brown but when newly molted they can be soft-bodied and white. Adult wireworms are beetles that have the ability to flip themselves upright when placed on their backs, making an audible click as they do, giving them their name "click beetles."

Wireworm (larvae).  Photo source Bayer CropScience.

Scouting
At this stage, bait traps won’t be a good indicator of potential wireworm infestations. I suggest you monitor areas with yellowing, pale green, wilted plants or areas that are not performing like the rest of the field. Typically you’ll find several plants within each furrow that are pale yellow or wilting sitting next to a healthy green plant. Dig up the effected plants and look for damage to the seed. 

Damage
Sometimes wireworm damage is confused with cutworm damage. Remember that with wireworms the plant is wilted and discolored but remains attached to the root. With cutworms the plants are usually cut off completely at or near the soil surface.

Economic Thresholds
An action threshold of about 32 wireworms per square meter (sq. yd.) is often recommended. If wireworms are found at this or a higher density, seed treatment is usually warranted in following years. The cost of a wireworm seed treatment is roughly $4.00 an acre over and above regular fungicidal seed treatments.  

Control Tips
There are only two registered wireworm seed treatments on the market today. The first is CruiserMax®, which contains the active ingredient thiamethoxam and Raxil WW which contains the active clothianidin. Unfortunately, if wireworms are found in an emerging crop, there is no 'quick fix'. Often, the damage occurs or is seen too late to reseed the damaged patch. The goal with wireworm treatments is to reduce the populations in the future. Also, the loss in yield does not justify the cost of re-seeding. The best plan is to consider what action may be necessary for the following year.

Sources: Canola Council of Canada, Saskatchewan Agriculture, Manitoba Agriculture

For more information on wireworms, refer to the following links:
Larval stages http://www.gov.mb.ca/agriculture/crops/insects/fad28s00.html
Management strategies http://www1.agric.gov.ab.ca/$department/deptdocs.nsf/all/prm2509?opendocument

Controlled traffic trials and tribulations

We finally finished seeding Tuesday morning after a month-long haul to get our modifications ready for ctf. There were several challenges put in front of us that put our seeding way behind schedule. I guess that’s the cost of trying to be innovative! Here’s a short list of some of the things we’ve learned in the field:

• A 30 ft ctf system is extremely effective but inefficient. I was able to achieve 14 acres per hour in canola and 20 acres per hour in wheat and barley. I think you would be much better off switching to disk openers that allow you to travel twice the speed and begin achieving 28 to 40 acres per hour. 
• If you’re going to move to ctf and offset your hitch each year to perform inter-row seeding, make sure the GPS receiver on your cab is centred with the drill hitch. If your receiver is mounted 3 inches off centre to your hitch and your drill is offset 3 inches the other way, you will have no offset! 
• The Can-Net VRS wireless RTK network with Rogers network data plan worked 98% of the time. We ran into poor reception on a few hills but had RTK fix up to 60 km away from the base station.
• Never use the nudge button on your GPS when you’re part way through the field and have already chosen your AB line. Nudging the GPS will leave an unnecessary overlap at the end of the field.
• There may run into side draft issues which can reduce the accuracy of your offset hitch depending on what kind of drill and opener style you have. The drill may skew a touch sideways as it pulls from a slight angle.
• If you’re going to down size your drill, I think you’d be better off just trading in your current one for a smaller drill.
• The air tank if full will wonder off the tram lines slightly. To perfect the ctf system on hilly ground you may need implement steering and air tank steering to keep everything on the tram line.
• We started up and our air tank ran 12 inches of the tram line. Be sure to have your steering arms on the front axels aligned so the air tank follows true.

So, the seeding is done, the torch is cooling. Now I’m looking forward to learning how to use the sprayer. I’ll keep you posted. SL

Market News

Technical Analysis

Canola: November futures. The short and long term trend is up.
HRS Wheat: December futures. The short and the long term trend are down.
Corn: December futures. The short and long term trends are down.
Soybeans: November futures. The short term trend is down and long term trend is up.
Canadian Dollar: June futures. The short term trend is up and the long trend is down.
US Dollar Index: June futures. The short term trend is down and the long term trend is up.