Agronomy

Last week ended one of the longest spray seasons ever for a lot of producers, including myself! It’s not often we’re still spraying fungicides on wheat at the end of July but when your planting window starts at the end of April and ends at the beginning of June, things drag on and on. I’ve recommended fungicide on all 14,500 acres of wheat across my territory this year to protect against septoria, tan spot, leaf and stripe rust. Thankfully, it’s come to an end and we can take a breather before the harvest equipment gets pulled out.

I’ve been asking around for fertilizer prices from a number of retailers and it looks like 46-0-0 is sitting around $570-580/T, 11-52-0-0 at $770-780/T, 0-0-62 at $650/T and 21-0-0-24 at $450/T. It doesn’t sound like many are buying at those prices with so much uncertainty in commodities lately. It may not be a bad idea to buy a few tonnes to hedge the risk, especially if you have 2012 crop priced already.

This week’s newsletter will show you how to estimate yield loss from leaf disease in wheat and barley. Next, we’ll look at field pea desiccant options and I’ll provide some quick facts on temperature effects on canola during flowering and an update on the use of plant growth regulators in barley. I’ll finish with some observations I’ve made in our barley now that we’re year two into CTF. We’ll end with technical and fundamental grain market news.    

Crop Staging Area (Calgary to Drumheller to Three Hills)

Seeded	May 1-7	May 8-15	May 16-21	May 22-29
Wheat	soft dough	milky dough	early milk	watery ripe
Canola	early pod	end of flower	late flower	mid flower
Barley	soft dough	milky dough	early milk	watery ripe
Peas	mid podding	early pod	late flower	mid flower

Steve’s tips of the week   

• The window for spraying wheat midge ends at the beginning of 80% flowering. Numbers have dropped off dramatically.
• Continue to monitor for stripe rust in wheat if you haven’t applied a fungicide. I’ve had a host of calls from Southern Alberta wondering about fungicide staging. If stripe rust is severe in the area I will use an application window up to milky dough.
• Begin sweeping for lygus bugs in canola that has now finished blooming. My personal threshold for lygus bugs is 4 per sweep at the end of flower.
• If you plan to straight cut canola, watch fields as they come out of bloom to give you an idea of which fields are the most even and best candidates for straight cutting.
• Start looking at pricing fertilizer.

Agronomy

Estimating Yield Loss from Crop Diseases

By now we've made the decision to spray or not to spray for leaf diseases in cereals. We are quickly approaching the point to which you can actually estimate whether your decisions were correct or, sadly, not.

Leaf diseases

To estimate yield loss from Net Blotch, Scald, Tan Spot or Septoria, examine crop at the milky dough stage. Assess at least 25 main stems two diagonals from one corner to the opposite corner of the field. Then assess the average percentage of the top two leaves affected. The calculation for percent yield loss is: 0.66 × % area of flag leaf infected + ½ × % area of second leaf infected ÷ 2.

For example, you find disease present in wheat on 20% of the flag leaf and 30% on the leaf below. The percent of yield loss would be:

0.66 x 20 + ½ x 30 ÷ 2 = 6.66% + 5% ÷ 2 = 14.1%

Therefore, your calculated yield loss is 14.1%. At $6.92/bu wheat and a yield potential of 50 bu/ac, you have lost 7.05 bu/ac (50 x 14.1%). That loss translates to $48.76/ac (7.05 bu/ac x $6.92/bu). The cost of a fungicide is roughly $11.00/ac plus $8.00/ac for application for a total of $18.00/ac. So, the return on your fungicide investment is $48.76/ac - $18.00/ac = $30.76/ac or 171%.

Proper disease scouting pays dividends especially when conditions are mild and humid like we've experienced this year. For the first time ever, I’ve recommended a fungicide on every acre of wheat I consult on. With more than 10 inches of rainfall and yield potentials in the 60-90 bu/ac range, a fungicide investment provides a very good return on investment. SL

Yield loss potential by disease

Field pea desiccant options

The standard option for drying down field peas prior to harvest has always been Reglone. Most cringe at the $20.00/ac price tag but for the most part it works quickly, provided the timing is right and cloudy but not rainy weather follows application. The second option is simply 1 L/ac equivalent of glyphosate at a cost of $4.00 ac, which gives you perennial weed control but a very slow dry down process. The third option being explored is applying the product called Heat at 10.5 g/ac with 0.5 L/ac equivalent of glyphosate plus Merge at 200 ml/ac for a cost of $6.25 ac. The goal is to offer a cost effective method of adding some weed control with a dry down faster than glyphosate but a little slower than Reglone.

I had a chance to tour some field pea plots recently that compared these three options. In the picture you see here, we have Reglone on the left, Vantage Plus Max at 1 L/ac equivalent in the middle and Heat-VantagePlusMax-Merge on the right. This photo was taken ten days after application. It is clear that Reglone works and you get what you pay for. Straight glyphosate works well so long as you have time to wait for dry-down. What wasn’t impressive was the Heat-glyphosate-Merge treatment. At $6.25/ac it may be cost effective, but it just doesn’t give you the dry-down you need to speed up harvest nor the perennial weed control you’d want if you were adding glyphosate. Perhaps you could add another 0.5 L/ac equivalent of glyphosate to the Heat-Merge combo for another $2.00 ac but the speed of dry-down will still be limited. 

In the end, you get what you pay for. Reglone, although expensive, can really help speed up harvest provided the right conditions are present. Glyphosate works just fine so long as you have time to wait it out. The Heat-Glyphosate-Merge combo in my opinion should go back to the drawing board. I don’t know if BASF’s seeking registration or not. Regardless, stick with one of the first two options for now. SL

Quick facts on temperature effects on canola flowering and yield

Canola is a cool season crop that prefers temperatures between 13oC and 20oC during flowering. At temperatures above 20oC yields begin to drop as the higher temperatures shorten the time the flower is receptive to pollen as well as the duration of pollen release. To explain further, canola plants cannot produce a sufficient amount of indole acetic acid (IAA) for cell division at high temperatures. The process of cell division and IAA production is needed to control bud formation, flower formation and fertility. So, without sufficient IAA, buds go dormant, flowers become sterile or don't form properly at all.

Reference: stollerusa.com

Growth regulators key to managing high yielding barley

I’ve been working on a high yield barley project with four producers this summer. The goal is 160 bu/ac malt barley and 180 bu/ac feed barley.  You can imagine at those yield targets, the seeding rates and nitrogen requirements are high, with 155 to 177 lbs of seed applied and 130 to 140 lbs/N/ac. High nitrogen rates and heavy plant stand densities are a recipe for lodging and in my opinion one of the biggest risks in barley production. With that in mind we set out to build a strong root base and add support with a plant growth regulator (PGR). So far, the plan is working beautifully.

We applied a PGR at the stage where 1 to 3% of the awns are just starting to emerge on the main stem. This timing allows the third and fourth tillers to mature enough to hit flag leaf. Applying a PGR prior to flag leaf can damage kernels and shorten heads and the same if applied too late at heads emerged. Unfortunately, the ideal stage of awns emerging lasts for about 10 to 12 hours before the window closes so execution is critical to success. Yield can be drastically reduced if a PGR is applied at the wrong time or when the crop is under stress. The key to proper timing is targeting high plant densities to minimize tillering. 

The results of our PGR applications were better than expected as you can see in the photos. The photo on top shows a ten inch difference in height with our PGR compared to the check. The heads and kernels are intact and filling nicely. The photo below shows the difference in height and the ability to prevent lodging. The lodging you see is a draw that runs through the field and the lodging ends where the PGR begins.

There are very few PGR’s in the market place.There is Ethrel from Bayer CropScience and Cycocel from BASF. I’ve been told that Syngenta has a PGR in the US but hasn’t sought registration in Canada. I really believe that the secret to high yielding barley is the use of PGR’s under an intense management system. High seeding rates and high nitrogen rates are necessary to produce 160+ bu/ac barley and our varieties just don’t stand up. Even a split application of nitrogen would have a hard time keeping plants short enough to keep 180 bu/ac barley standing after a heavy wind or summer rain storm. In the end, I know that I’ll be having the discussion with my barley growers this winter to see what kind of intensity we can manage and execute PGR’s properly. 

High yield 180 barley project is funded by the ACIDF, the Alberta Crop Industry Development Fund and the Alberta Barley Commission.  SL

Update on kernel and head counts in year two of CTF

I had a chance to make some observations in our barley yesterday, now that we’re closing in on harvest in our second year of CTF. I was comparing head and kernel counts across the rows inside the tram line, beside the tram line and three rows outside of the tram lines to see what effects our hard packed tram lines have on yield. 

Our drill is set up with two inch GEN sideband openers on twelve inch spacing and a hitch that allows us to inter-row seed. We also have two seed tubes coming into the openers on each side of the tram lines to help boost plant densities while removing one opener in each tram line. Keeping the tractor and air tank stationary means our drill has to move six inches side to side each year to seed between the rows. This movement shifts openers inside and out of the tram line and forces some rows to grow six inches inside the tram line, which is not a very hospitable environment. Here are the details of my measurements:

Row	Heads/ft2	Kernels/head
Inside tram line	68	18
Beside tram line	74	19
Three rows outside tram line	74	22

It’s obvious that we’re getting a higher seedling mortality rate inside the tram line with only 68 heads and 18 kernels per head, and that’s after doubling the seeding rate with two seed tubes. The head count increased by 8% in the row beside the tram line but the number of kernels per head was almost the same. The crop growing three rows outside of the tram line had 9% more heads and 22% more kernels than the row inside the tram line.

Its obvious that compaction in the tram line is causing a reduction in tillering and head size. The row beside the tram line had excellent tillering and head counts, but the number of kernels per head were affected. The crop three rows outside the tram line had excellent tillering and kernels per head, in fact a 22% increase in kernel numbers and an 8% increase in number of heads per ft2.

Visually you can’t see the difference in kernel number in the rows beside and outside of the tram lines. Take these same results and move them into a random traffic system where a sprayer has covered 5% of the field after two passes and a tractor and drill has covered 20% of the field. You could add in 10 or 15% from last years wet harvest traffic and voila, you’ve got just over a third of each field subject to a loss in yield. Twenty percent less kernels per head is massive but goes easily unnoticed. That’s just a quick update on the observations I’ve made prior to harvest. We will be harvesting individual rows this fall to find out what the true difference is. Once again, I’m convinced that we’re on the right track with CTF.

Controlled Traffic Farming Field Day

The last CTF field day will be on August 4 near Jarvie/Dapp. The event starts at 1:00 PM and finish at 4:30pm.

Thursday, August 4th, 2011, Jarvie/Dapp, AB, at James Jackson’s farm.
See map: http://maps.google.ca/maps/ms?hl=en&ie=UTF8&msa=0&msid=215521258858434624136.0004a15f5c33955fae7e6&ll=54.384156,-113.969421&spn=0.103365,0.338173&z=12

Topics:
Equipment setup and modifications
First year observations
Crop walk looking at:
soil variability,
soil quality,
zone mapping
nutrient status
variable rate fertilizer
Controlled Traffic Farming Alberta project update.

There is no charge for the event. Refreshments will be provided. 3 Soil & Water Management CEU's for CCA's. For more information go to: http://canola.ab.ca/controlled_traffic_farming_field_day_trochu.aspx