June 19, 2012

Agronomists Notes

Hello Reader,

Crops are progressing nicely across the territory. Canola is beginning to bolt and late-April seeded barley is coming into flag leaf. Crops are shorter than normal given the cooler temperatures but then again temperatures are ideal for head development in cereals. I’ve completed my first round of field checks and am moving into the second round to make sure herbicides worked properly and to monitor insect and disease pressure. There is excessive moisture stress showing up in a few areas after 3 inches of rain last week on top of earlier rains.

Are you feeling a little behind on spraying after showery weather, windy or cool conditions last week? This week looks to be the same with showers called for almost every day. Disease could soon be an issue in these conditions and current crop stages.

In this week’s newsletter, we’ll look at the robustness of a controlled traffic system after 4 inches of recent rains and give you a tidbit on applying copper to boost wheat yields. Next, as we come into fungicide season I’ll give some tips on how to predict flag leaf emergence in wheat and barley. I’ll also talk a bit about my observations of the paired row opener on the John Deere ConservaPak. We’ll finish with boron applications and stripe rust identification and control. As always, we’ll end with technical grain market news.

Have a great week.

Crop Staging

(Calgary to Drumheller to Three Hills)

Seeded    Apr 24-30         May 1-7             May 8-15
Wheat      1st node           6 leaf 2 tiller      5-leaf 2 tiller
Canola     bolting              bud stage          6-leaf
Barley      flag emerging   2nd node           5 leaf 2 tiller
Peas        11th node         10th node           8th node

Steve's tips and tricks of the week

Follow me on Twitter for in-season updates @BeyondAgronomy

Be sure to check your herbicide efficacy on crops sprayed 10-14 days ago. Catch the escapes before they get away.
Start staging late April early May seeded cereals as they are coming into flag leaf.
Book your fungicide today to avoid using what you have to instead of what you want.
Conditions and timing of foliar boron in canola and copper in cereals is here. (bolting, stem elongation)
Monitor disease pressure in cereals. Is disease creeping in already?

CTF offers excellent drainage after heavy rains

Last week we had just about four inches of rain fall within a few days bringing us to 7 inches total for the season. There was water laying on the surface of most fields and erosion in neighbouring fields. The top photo you see here shows water lying in our tram lines. The photo below is of a neighbouring field that is managed in a conventional system with an air seeder followed by harrow packers. The water was lying across the entire field and running off compared to the CTF field where water was being absorbed into the soil and only standing in the hard packed tram lines and natural draws.

I suspect we captured a large percentage of that rain which will hold us until harvest even if don’t get another drop. I didn’t notice any erosion on our tram lines as we’re told to expect by the professionals. The key is keeping high residue levels in the tram lines to slow any moving water.

Every year we are more convinced that our CTF system offers a more robust production system compared to randomly farmed zero-till fields. We could be on the field Thursday for in-crop herbicide application, barring any more showers. Improved timeliness of field work is one of my favorite benefits of CTF. SL

Pictured above: Water ponded in the tram lines and natural draws in our CTF field near Morrin, AB.

Correcting copper deficiency in wheat

The quick and dirty on applying foliar treatments

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 treating 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 one-time 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 the 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, ATP Nutrition and Nexus just to name a few suppliers. 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 Agriculture

Predicting flag leaf emergence for fungicide timing

Barley (2-row)
When the third node is about half an inch above the ground, the penultimate leaf (one just below the flag) is visible, and the next leaf to appear is the flag. If only one node is visible, then it will be about 10-14 days till flag leaf; if two nodes are visible it will be about 5-7 days until the flag leaf is out.

Barley (6-row) and wheat
When the second node is half an inch above the ground, the penultimate is visible and the next leaf is the flag. If only 1 node is visible, the next leaf will be about 5-7 days. The flag leaf is usually the seventh or eighth leaf in cereals. In wheat, the flag leaf is large and contributes to 45% of the yield. The penultimate leaf contributes another 10%. In a barley crop, the flag leaf is smaller so the penultimate and flag together contribute 65% of the yield.

Source: Syngenta

John Deere Conserva Pak 2-inch opener effects seed placement

I have a side-by-side trial going on comparing the JD 1870 ConservaPak precision drill with a JD 1830 hoe drill in canola. The JD 1870 came equipped with a 2-inch paired row opener and the JD 1830 came with a 3.5-inch paired row low draft Dutch opener with 5-inch flat rubber semi-pneumatic packers. After my first walk through I noticed a big difference in seed placement and a small difference in emergence.

Believe it or not the JD 1830 had better seed placement as you can see in the photo here, but less emergence compared to the JD 1870. The JD 1830 with wide openers laid the canola in the furrow nicely at 0.75-inches but had 15% less seed emergence compared to the JD 1870. The JD 1870 with the paired row opener had a high degree of variability in seeding depth which you wouldn’t think could happen with an 1870 Conserva Pak. I’ve been told the JD 1870 was never designed to use a paired row opener but farmers across Western Canada demanded it. I can see now that the Conserva Pak doesn’t work well with a paired row because it totally messes up seeding depth.

Oddly enough, even with the high degree of variability in seeding depth with the paired row on the Conserva Pak it still had better emergence compared to the JD 1830 with the 3.5-inch paired row low draft Dutch opener. Even with consistent seeding depth the emergence was lower which leads me to believe it’s a packing issue. With wetter spring conditions, the flat rubber semi-pneumatic gang packers on the JD 1830 over packed the seed. I could feel the 0.5-inch layer of hard soil above the seed and see the sprouts that failed to emerge.

The biggest lesson from this trial so far is the variability in seed placement with the JD 1870 when using a 2-inch paired row opener. The single knife opener on the JD 1870 does a great job of seed placement but I’m finding the paired row does not. If you’re thinking about the paired row option on the JD 1870 Conserva Pak, I’d lean toward the single knife opener instead. You’ll be a lot happier with the seed placement and emergence.

Pictured above: Seeding depth comparison on JD 1870 Conserva Pak with 2-inch paired row opener and JD 1830 3.5-inch paired row low draft Dutch opener. Source. S. Larocque

Late season annual sow thistle control in peas

We’ve all noticed or personally experienced pea fields full of sow thistle late in the season. Here’s something we can do about it. I use a little trick just prior to peas coming into flower: 500 ml/ac of Basagran Forte in Headline at the very start of flower. In my experience the Basagran Forte wiped out late flushing 2 to 4 leaf annual sowthistle and come harvest the field was spotless. Thre treatment isn't cheap at roughly $13.20 acre but the results are excellent. The combination of Headline fungicide and Basagran Forte herbicide is not registered so I would refer to your local BASF rep before you try this combination. SL

Now is the time for boron applications in canola

With the recent wet weather and canola beginning to bolt, some coarse textured soils may experience some temporary boron deficiencies. Boron is highly leachable and can move below shallow rooted canola plants like we have this year. Deficiency at this time can lead to terminal bud death, poor pollination and failure to produce flower buds. The addition of foliar boron in a responsive situation can lead to a 5-10% yield bump. Boron deficiencies are favored by pH's below 5.5 and above 8, excessively wet, dry or hot weather and low organic matter. Also, excessive sulphur fertilization can inhibit uptake of boron.

The tricky part about boron is that it is immobile within the plant so it needs to be constantly supplied to the new leaves or growing points. When tissue testing, the key is to take canola leaf samples from the youngest leaves. The older leaves can actually accumulate boron in a deficient situation and throw the tissue results out of whack.

Soil test range
Deficient: 0 - 0.5 ppm
Medium: 0.5 - 1 ppm
Adequate: >1.2ppm

Tissue test range
Low: <20 ppm
Marginal: 20-30 ppm
Sufficient: >30 ppm

Thankfully, correcting a boron deficiency can be as simple as applying foliar boron from bolting to flowering. However, if heavy rainfall conditions continue or hot weather above 25C occurs, a second application of boron may be necessary to maintain a constant supply. Here's a list of products to correct a boron deficiency:

Stoller MP Boron 9% B, $7.50/L, apply 0.5 to 1L/ac
Omex Potato MB 4% urea 10% boric acid, $6.50/L, apply 0.5 to 1L/ac
NutriAg BoronMax 8.1%, $7.00/L, apply 0.2 to 0.8 L/ac
Nexus Liquid Boron 10%, $7.00/L, apply 0.5 to 1 L/ac
UAP Borosol 10%, $6.35/L, apply 0.5-1.5 L/ac

To optimize foliar boron response, be sure to apply it during times of high humidity like late in the day or early morning to give the best chance of response. You want the droplet to stay on the leaf for as long as possible to ensure passive transport through the leaf cuticle and stomata. Be sure to talk to the local product reps and ask about the appropriate application rates given their experience in your area. SL

Stripe rust identification and control

The infection level and incidence of stripe rust has increased in Southern Alberta over the last two weeks. With many crops not yet flag leaf, we’ve got a perfect storm brewing with host, pathogen and environment being ideal for stripe rust development. Be sure to book your fungicide today and please don’t mess around with three-quarter rates. With stripe rust arriving early, wet conditions and a long way to grain fill you’ll want as much protection as possible. Here are the details on stripe rust and the control options.

Identification and yield loss
Stripe rust can be identified as small orange-yellow coloured pustules forming in vertical lines along wheat leaves. This disease can result in yield losses of 10 to 70% in susceptible varieties and total yield loss has been reported when severe epidemics occur. Like other leaf and stem diseases, yield losses are roughly proportional to the plant area infected. Yield losses are generally most severe when the infection occurs prior to heading. Historically stripe rust has not been of economic significance in western Canada but incidences of the disease have been increasing over the past 4 or 5 growing seasons.

Conditions for development
The major source of rust spores in Alberta is carried by south winds from the Pacific North West. Wind direction and a specific range of temperatures are essential for the onset and development of stripe rust. For example, relative low temperatures and moisture favour development. Urediniospores germinate optimally between 5 and 15oC with limits near 0 and 20oC. Disease development is most rapid between 10 and 15oC with intermittent rain.

Monitoring
If you are growing a susceptible variety, it is important to scout every few days starting with the bottom leaves. Know the visual symptoms of stripe rust and monitor fields in the morning when new spores are distinctly yellow. See stripe rust tolerance ratings below.

Threshold
Spraying should be done when stripe rust reaches 1% of flag leaf area and before it reaches 5% of flag leaf area. Once this infection level is reached, stripe rust becomes very difficult to control. The period of infection to the release of spores is as little as 8 days, which can result in multiple generations per growing season.

Growth stage
Apply fungicide at flag leaf or before wheat has flowered. Fungicide treatments made past the flowering stage rarely provide an economical benefit.

Fungicide Options: These costs are before rebates.
Caramba: 283 ml/ac, $13.50/ac
Folicur EW: 200 ml/ac, $11.85/ac
Prosaro: 320 ml/ac, $15.45/ac
Quilt: 405 ml/ac, $11.70/ac
Headline: 160 ml/ac, $11.50/ac
Twinline: 200 ml/ac, $9.85/ac
Tilt: 202 ml/ac, $7.50/ac
Stratego: 200 ml/ac, $7.50/ac

The most effective fungicides on the market for control of stripe rust are Folicur EW, Prosaro, Quilt, Twinline and Headline. SL

Stripe Rust Tolerance Ratings

(Scroll down to page 5 for hard red spring varieties and look for the stripe rust column for ratings.)