Agronomist Notes

Another inch to three inches of rain fell across my territory last week which has delayed spraying somewhat. It seems like everyone is on to Liberty herbicide and can’t catch a warm day or sunshine. The next few days look promising thankfully.

So far herbicide efficacy has been excellent with rapid uptake and quick results. The humid weather has even created a touch of surfactant burn on the leaves in crops like Liberty Link canola. On the crop development side, some crops have remained short from moisture stress and cool soils, most of them wheat on canola stubble.

In this issue we’ll discuss correcting copper deficiencies and look at a successful tool for managing heavy wild oat pressure. Next, I’ll update you on some compost versus fertilizer trials and the success we’ve had adding ammonium sulphate to improve Centurion performance. Last, I’ve provided a handy phenoxy conversion chart to calculate active ounces per acre anda handy tool used overseas to estimate canola nitrogen application requirements. We’ll finish with fundamental and technical grain market news.

Agronomy

Crop Staging Area (Calgary to Drumheller to Three Hills)

Seeded	May 1-7	May 8-15	May 16-21	May 22-29
Wheat	first node	5 leaf 2 tiller	4 leaf 1 tiller	3 leaf 1 tiller
Canola	bud stage	6 leaf	5 leaf	3 leaf
Barley	5 leaf 2 tiller	4 leaf 2 tiller	3 leaf 1 tiller	3 leaf
Peas	13th node	10th node	7th node

Steve’s tips of the week

• Expect surfactant burn or leaf bronzing in Liberty Link canola from high humidity levels. Not to worry, it’s merely cosmetic and doesn’t lead to yield or maturity loss.
• Tissue test for suspected sulphate or nitrate leaching in sandy or coarse textured soils (especially canola). Shallow roots may not be able to pull sulphate from below the root zone. Watch for thin spindly bolting canola.
• Be sure to do your post-herbicide spray checks to make sure herbicides worked well. If the product didn’t perform, you’ll have time to re-spray and correct the problem before it’s too late.
• Stick to herbicides with 1 hour or less rainfastness when possible. Showers remain in the forecast.
• Early-May seeded wheat is reaching the first node stage; an excellent time for correcting copper deficiencies with foliar copper.
• Tan spot is showing up a great deal in heavy wheat rotations. Plan to apply fungicide at flag leaf through heading.

Unfortunately we have had to postpone the Morrin Tour until June 29 due to rain.

Controlled Traffic Farming Field Day – Rain delay

New date: Wednesday, June 29

Morrin, Alberta: One mile west of Morrin on HWY 27 and 1.5 mile north on RR 20-4 (N 51 40.234 and W 112 47.543)

1:00 PM – 1:30 Sign in

1:30 – 1:45 Introductions and CTFA project (Peter)

1:45 – 2:45 Steve Larocque’s system/equipment and year two experiences

2:45 – 4:00 Cropwalk and commentary led by Steve and Roger Andreiuk

4:00 – 4:30 Wrap-up discussion

Join us to look at the second year of Steve Larocque’s controlled traffic farming near Morrin, Alberta.

Equipment modifications

Second year observations

Cropwalk looking at:

• soil variability,
• soil quality,
• nutrient status and
• inter-row seeding
• Controlled Traffic Farming Alberta project update.

There are 3 Soil & Water Management CEU's available for CCA's.

There is no charge for the event and you do not need to register. Refreshments will be provided.

For updates please check  www.controlledtrafficfarming.org – click on CTF Events.

For more information on CTF Alberta visit their website, Facebook, Twitter and discussion forum or contact Peter Gamache, Project Leader 780 720-4346.

The quick and dirty on correcting a copper deficiency in wheat

If you suspect a copper deficiency in some of your wheat fields either from previous soil tests, tissue tests or visual signs like pig tailing leaf tips now is the time to start correcting it. Studies have shown a foliar application of chelated copper in season can work well to correct a deficiency.

With foliar applied copper you have two options with regards to timing. You can apply a split application in wheat at the first node stage (Feekes 6) with a follow up application at flag leaf (Feekes 10). This strategy may help to prevent some early season deficiencies. Some producers have gone with a 0.1 lb/cu/ac the first application and another 0.1 lb/cu/ac on the second application. A onetime application of foliar copper at 0.2 lb/ac is also effective at flag leaf but one has to be cautious of phytotoxicity, especially when tank mixing with fungicides.

Early-May seeded wheat is now coming into or first node stage (Feekes 6). If you suspect a copper deficiency, now is the time to act whether you plan on a single or split application. There are a number of foliar copper products on the market from Stoller, NutriAg, Omex, WolfTrax and Nexus just to name a few. Be sure to consult the product representative to find out tank mix options, timing and product rates. A well timed copper application can mean a reduction in lodging, ergot as well as higher kernel weight and protein content. SL

Copper information from Alberta Ag: http://www1.agric.gov.ab.ca/$department/deptdocs.nsf/all/agdex3476

PrePare helps reduce heavy wild oat populations

I have a client who has a few fields with heavy wild oat populations, the kind of fields that normally need to be sprayed twice for control. We missed a fall application of Avadex and needed a solution this spring. I decided to try 480 acres worth of PrePare on three fields. PrePare is a pre-seed burndown herbicide that contains 8.7 g/ac of flucarbazone-sodium (same active ingredient as Everest) plus a 0.5 L/ac of glyphosate equivalent. The rate of flucarbazone in PrePare is approximately 60% of what you’d normally apply Everest 70 WDG at in-crop. The goal is to control the early flushing wild oats before they get established and begin to rob nitrogen and yield.

The results are in and I’d say the PrePare worked exactly as it was intended across the 480 acres. Some of the heaviest areas of wild oat pressure and I’m talking 100 wild oats per ft2 were reduced to just 1 to 3 per ft2. The 8.7 g/ac was enough to reduce wild oats populations by 80 to 90%. We’ve followed up with another 8.7 g/ac in-crop and expect similar results.

In my opinion, if you’ve been in no-till for five, ten or twenty years, the majority of the wild oats are sitting in the top two inches. Products like PrePare can work very well to control the majority of wild oats that germinate in the top inch or two. Much like Avadex or Edge if the wild oats germinate from below the treated layer, they will grow through the treated layer and remain unaffected. If the field has a history of cultivation which tends to bury wild oats, then PrePare may not give you the control you’re looking for. I’d start pulling up wild oats in your worst areas now to see where they are germinating from. At a retail price of $8.00 an acre, the Prepare more than provided an ROI on the fields we treated. SL

Compost versus fertilizer trials

A client of mine has been running a field scale 320 acre side by side trial using 3 T/ac of compost/gypsum plus starter fertilizer and comparing it to straight fertilizer. Each year I get disgusted by the look of the plants grown in the compost field. They just don’t look as lush or healthy green as the fields using fertilizer. See the picture here with plants taken from the compost side versus the fertilizer side. You can see the plants are noticeably larger and a full leaf stage ahead of the compost. Before I lead you on further, would you believe we’ve seen no difference in yield in the last three years in spite of the way things “look”?

Here are the details:

Wheat: 130 lbs/ac AC Harvest with Raxil MD seed treatment
Planted: May 5th

Fertilizer: 90-25-0-0 @ 232 lbs/ac = $44.00/ac

Compost: 3 T/ac = $45.00 (includes trucking and application)
Starter Fert: 20-20-0-0 @ 72 lbs/ac = $15.23/ac
Total cost: $60.23/ac

This trial is costing $15.23/acre more to apply compost compared to conventional fertilizer at today’s fertilizer prices. Once fertilizer prices climb above $700 tonne again, even with the starter fertilizer the compost can be just as economical. One of the down sides is the potential for compaction having all that traffic applying compost each year. Also, the compost doesn’t perform as well during periods of drought so a dry start to the year may reduce nutrient release and yield. In the end, compost does have some merit given the similar yields it’s produced over the last three years compared to conventional fertilizer. If fertilizer prices continue to climb, products like compost start to make sense. By the time that happens, we’ll have several years of yield and application data to draw from to help us move forward with confidence. SL

Adding ammonium sulphate to Centurion improves grassy weed performance

Nearly all of my clients have well water that tests over 400ppm in bicarbonates and in previous years some have struggled to control volunteer barley and wild oats in Liberty Link canola. Bicarbonates tie up clethodim (Centurion) and render it unavailable. For two seasons now, I’ve recommended adding ammonium sulphate at 1% v/v to Liberty and Centurion tank mixes to improve grassy weed control. The addition of ammonium sulphate conditions the water, tying up the bicarbonates so clethodim products work better.

The picture here shows the effectiveness of adding 1% AMS v/v to control wild oats. The spray water contained 600 ppm of bicarbonates and we only applied an 80 ac/case rate of Centurion with 1.35L/ac of Liberty. You can see in the picture the wild oats are toast just 8 days after application. We struggled in years previous to control volunteer barley and wild oats at this rate. Not anymore. SL 

Rate of AMS at 1% v/v
10 US/gal/ac: 378 ml/ac
10 IMP/gal/ac: 454 ml/ac

Photo source: Steve Larocque

Phenoxy rate chart

We’re getting to the stage where some weeds are getting larger and producers are adding a few ounces of MCPA or 2,4-D to certain herbicides to heat things up. To help you navigate through the usual confusion with our trilingual application language, I’ve attached a handy chart which converts ounces of active 2,4-D or MCPA to ml/ac or ac/jug. So whether you’re talking grams of active per litre or ounces per acre or ml/ac or ac/jug, this chart will help you concoct the right dosage. 

Insert phenoxy rate chart.

Optimizing leaf area index key to achieving high canola yields

One of the key drivers in canola yield is leaf area index or what’s commonly known as green area index (GAI). GAI is the ratio of green plant material that covers a square meter of land and has a direct influence on crop vigour, root development, moisture use efficiency, weed suppression, carbohydrate storage and nutrient transport. In a nutshell, obtaining optimum GAI’s can build bigger canola yields with less water and nutrients. 

In November 2009, I had a chance to discuss the use of green area index measurements with Nick Ward, farmer and Nuffield Scholar from Linconshire, UK. Nick measures GAI in his canola to calculate nitrogen uptake and application rates in order to achieve optimum GAI and yield. I had Nick explain how UK producers use green area index to measure nitrogen uptake and calculate nitrogen application rates:

Measuring Green Area Index

1. To quantify the amount of nitrogen taken up by the crop prior to bolting, a 1 square metre quadrant is placed in a representative area of crop. The entire green mass (stems and leaves) on this area is cut off at ground level and weighed (including dead leaves). Alternatively you can take a picture of 1 square metre of area standing above the crop and insert it into the BASF GAI online measurement tool  http://www.totaloilseedcare.co.uk/canopy-management/GAI/index.html
2. The weight of the green mass (stems and leaves) is measured in kilograms and multiplied by a factor of 0.8. This will give you a Green Area Index number. For example, 1 kg of green mass from 1 square metre would equate to a GAI of 0.8. (1kg × 0.8 = 0.8 GAI) or (0.750kg × 0.8 = 0.6 GAI) 
3. Pictures of GAI examples.  http://www.hgca.com/content.output/852/852/Resources/Tools/Green%20Area%20Index%20Tool.mspx

Calculating nitrogen uptake and N application rate

1. It is assumed that each GAI of 1 contains 50kg/ha of N within the crop. If you want to convert kg/ha to lb/ac, simply multiply kg/ha by 0.893. For example, 50 kg/ha × 0.893 = 45 lb/ac of N within the crop. 
2. Now, multiply your GAI × 50 kg/ha to calculate the amount of nitrogen in the crop. For example: 0.75 GAI × 50 kg/ha = 37.5 kg/ha N within the crop or 33.5 lb/ac N
3. Next, the optimum sized canopy at full growth (bolting) has a GAI of 3.5. We need to build the crop canopy up to a target GAI of 3.5. Example: 3.5 - 0.75 = 2.75 GAI
4. To calculate the nitrogen necessary to build an additional GAI of 2.75 we need to multiply 2.75 GAI × 50 kg/ha. For example: 2.75 GAI × 50 kg/ha = 137.5 kg/ha N or 123 lb/ac N
5. Therefore, the crop needs 123 lbs/N/ac to reach its optimum canopy size and yield potential.

In Canada, a GAI of 4 is considered optimum for the crop canopy to intercept about 90% of the incoming solar radiation. (The picture above has a GAI of 1.8 to show you an example.) The larger the leaf area the crop can expose to the sun, the more dry matter the crop can produce per day. The more dry matter a crop can produce, the higher the yield potential. I’d like to run some numbers but instead, I’ll challenge you to start measuring GAIs in 2010. Start questioning what it would take to produce a GAI of 4 in your cropping system. Is it a change in row spacing, opener width, fertility program, nutrient placement, seeding rate, fungicide or variety? Let this be the beginning of a new way of measuring yield potential in canola. SL
 
Source: Nick Ward, Lincolnshire, England
Canopy photo source: GRDC

CWB seeding progress report – June 20, 2011

Seeding of the 2011 Prairie crop has now reached about 87 per cent complete, according to CWB weather and crop analysts. Widespread rains across the Prairies have dashed hopes of any additional seeding in the wettest areas of south-eastern Saskatchewan and south-western Manitoba, where precipitation ranged between 25 and 115 millimetres over the past week. However, the rain was welcomed in dry northerly regions, while near-normal temperatures promoted crop growth and development. Today (June 20) is the crop-insurance deadline for seeding across the Prairies, meaning little additional crop will now be planted.