July 24, 2012

Agronomists Notes

Hello Reader,

Seeding overlaps and draws have started to lodge in many areas and some localized areas were laid flat after last Friday’s wind storm. It’s difficult to say what the 10-day stretch of 30C weather did to wheat, canola and pea crop yield potential but we can safely say it took some edge off the yield.

Wheat midge scouting has come to an end as the later seeded wheat is finished flowering. Canola insects have been few and leaf diseases have been addressed. We can hopefully take a breather for the next week or so as canola finishes blooming.

In this week’s issue of Beyond Agronomy News, we’ll look boosting protein in wheat with late season foliar urea. Next, I’ll give you an update on the 24-inch row spacing in canola at Justin Nannninga’s. Also, we’ll look at boosting yields in canola with late season foliar urea at early podding stage. Last, I’ve provided some comments on the use of chlormequat as a plant growth regulator from a friend in Ukraine. We’ll finish with technical grain market news.

Have a great week.

Photo: Local aerial applicator applying fungicides in canola near Beiseker, AB, July 18th, 2012.

Crop Staging

(Calgary to Drumheller to Three Hills)

Seeded    Apr 24-30               May 1-7                  May 8-15
Wheat      milky dough           watery ripe              watery ripe
Canola     early pod               end of flower           70% bloom
Barley      milky dough            watery ripe              heads emerged
Peas        mid podding           early pod                 end of flower

Steve's tips and tricks for the week

Follow me on Twitter for in-season updates @BeyondAgronomy

Continue scouting for diamondback moth larvae in canola
Watch for signs of aster yellows in canola. It’s rare but late seeded canola crops may be at risk for leaf hopper damage, which causes aster yellows.
Look for early signs of sclerotinia in canola
Look for early signs of blackleg in canola

Boost proteins in wheat with liquid urea

We all know that protein offers a premium in spring wheat yet many producers struggle to achieve protein levels above 13.5%. The usual approach is to keep applying more nitrogen at seeding. That doesn't necessarily mean you'll reach high protein. More yield perhaps, but not more protein. Achieving high protein comes down to the timing and form of nitrogen applied. With potential protein premiums in 2012, perhaps we should take a second look at the way we apply nitrogen in spring wheat.

It's well documented that applying nitrogen during flowering or the doughy stage in wheat will increase protein. The problem we run into with our current one-pass system is the timing of nitrogen uptake. Applying all N at seeding leads to luxury consumption and tall leafy plants. Later in the season, nitrogen uptake is reduced during the reproduction phase. Root growth ceases during the reproductive phase which means roots are not actively exploring soil and taking up nitrogen. The solution, no pun intended, is liquid urea at flowering or milky dough.

Urea has a very small molecular size, a neutral charge and is readily absorbed into the plant through diffusion across the leaf membranes. Compare that to a product like 28-0-0 UAN or broadcast urea- these forms must be washed into the ground and then taken up by plant roots, which is totally dependent on rainfall after application. Also, UAN contains only 50% urea, the nitrogen form which can be taken up through the leaves. We still get a protein response from foliar applied UAN but the response is coming from the urea portion, not the nitrate or ammonium.

To give you an idea of the protein increases seen with urea rates here are just a few research examples:

Gabala, et al (2003), 9 lbs/ac of urea during flowering increased protein from 10.2 to 11.8%
Johnson and Perfine (2002), 9 lbs/ac of urea at milky dough increased protein from 9.9 to 10.8%
Svenson, et al (2002), 11 lbs/ac of urea at doughy stage increased protein from 11% to 12.2%

Steve's quick math
Assuming $7.50 wheat and 60 bu/ac yield
Application cost: $3.50ac app + 3% yield loss from wheel tracks = $17.00/ac
Urea cost: 11 lbs/ac × $0.32/lb ($700/T ÷ 2204lbs/T) = $3.52/ac
Total cost = $20.52/ac
1% protein increase: 60 bu/ac × $0.80/bu = $48.00

So, in this example, you could theoretically generate $27.48 an acre from the increased protein, provided you could achieve a 1% protein bump. If you don't account wheel tracks, you're looking at a $44.50 an acre net return on investment. Bottom line, liquid urea is a lower cost and more efficient strategy for applying foliar nitrogen to increase protein and something we should start testing in our system. SL
Reference

Update on 24-inch spacing in canola

Here’s a quick update on canola row spacing to get your gears turning for 2013. Justin Nanninga from Neerlandia, AB sent me some recent photos of the canola trials he’s working on this season. If you recall, Justin applied 1.5 lbs/ac of Liberty Link 5440 with a tkw of 5.13 and 98% germ and achieved 4.5 plants per ft2 on 24-inch rows.

To achieve 24-inch spacing on the Conserva Pak, Justin blocked every second run on the distributor with shop towel. Shut off valves were installed on the NH3 and liquid starter lines and hooks were built to keep the fertilizer knives out of the ground. Lastly, lock out bolts were used to hold the seed boots out of the ground.

This field has looked excellent from day one for a number of reasons. Yes, the precision planter helped achieve accurate seed placement and allowed Justin to seed down to 1.5 lbs/ac successfully. The second most important aspect of this system is that the canola had access to twice amount of nitrogen and phosphorus during the first phase of growth. When every second run is blocked, the fertilizer rate is effectively doubled, so in this case, plants had access to 60 lbs/ac of phosphorus applied as 10-34-0-0 liquid and 220 lbs/ac of nitrogen applied as NH3. With those rates and the issue of seed safety addressed, the plants didn’t have to work hard for nutrition during a key time.

The tremendous growth up front has translated into a closed canopy at flowering which is a real surprise on 24-inch row spacing, especially with a low plant density of 4.5 plants ft2. Justin has kept the weeds under control and now only has to wait for harvest on this trial field. Swathing may prove difficult or perhaps he may choose to straight cut.

Two things have me intrigued by this trial. The first is the potential to reduce seeding rates by 2 or 3 lbs/ac and still maintain a desired plant stand. That part translates into a $30.00 acre savings in canola seed. Not bad if we can repeat the success rate of this trial. The second and most important is the significance of fertilizer distribution. Doubling the fertilizer rate per row had this crop jumping out of the ground and producing a tremendous amount of biomass. Enough so that it covered the ground come flowering which is unusual for such a wide row spacing. When you think about the access to nutrients placed a few inches below the row at twice the fertilizer rate without doubling the fertilizer bill, I think we should pay closer attention to the benefits of wider row spacing. SL

Photo: A great canopy cover and plant density on the trial field. Source: J. Nanninga

Applying liquid urea at early pod stage in canola boosts yields

I discovered an interesting way to boost yield in canola after a chatting to a few UK growers and agronomists. Some producers in the UK apply liquid urea at the early pod stage to generate higher oil content and yield. The results they tell me have been mixed but in some cases they’ve found a 7 to 9 bu/ac yield increase from a 25 lb/N/ac application using liquid urea solution. I think a quick tissue test for nitrogen at the end of flowering could show you whether nitrogen is limiting in the plant. If there is adequate moisture in the soil profile, a liquid top dress of urea might be a new avenue to explore in our canola production systems.

The majority of producers are using liquid urea instead of liquid UAN (28-0-0) for its lower cost, increased uptake efficiency and reduction in leaf burn. That’s not to say that liquid urea doesn’t burn because it will under high light intensity or temperatures above 18C. The key to reducing scorch is water volume.

I’ve put together a list of tips used by my UK friend Nick Ward from Lincolnshire to give you some ideas. Here are his comments:

You can use any 46% urea and tip it into the water tank and circulate it using a pump. 'Distressed' urea is usually used (ie. sweepings out of a shed) as it is cheaper and doesn't need to have spreading quality.
We spray on 150-200 litres of 20% nitrogen solution per hectare at the end of flowering. (That works out to 25 lbs/N per 15-20 US gallons/ac.)
If temperatures are hot, apply in the evening. We don't dilute it, but if you were concerned about heat, dilute it with the same amount of water. I've applied the urea solution up to 23 degrees C and didn't have any problems with leaf burn.
20% is the max strength that you will get. I think granular urea may be the better option as prilled has an oily coating that leaves a film on the liquid.
For our main liquid fertilizer solutions we would use an ammonium nitrate/urea mix in solution to get the concentration up to 37%. But for this job a urea solution is a lot gentler and will cause way less scorch even in warmer conditions.

Here are a couple of points of my own:

Add 3.6 lbs of urea per gallon of water to give you 25 lbs/N per acre and apply solution at 15 gal/ac.
You can delay maturity with a late season nitrogen application so those who've finished flowering by late July, early August might be able to afford a slight delay in maturity.

Steve's quick math
Let's see what this nitrogen boost could pay back.
25 lbs/ac × $0.69 lb/N: $17.25 ac + $3.50 application = $20.75
50 bu/ac canola yield × 8% × $13.00 bu = $52.00 ac
ROI: 2.5 to1

In theory, if we were to see the same response as some have in the UK, the additional $20.75 ac investment in liquid urea may net you a 250% return on your investment. I think there is value in spreading out your nitrogen applications in canola and this might be a way to generate better nitrogen use efficiency rather than applying all of our nitrogen up front which by now is 90 days ago. Even a 5% yield increase at today's prices makes this option viable. SL

Your comments

Chlormequat as a growth regulator in cereals

I would like to share some information on chlormequat or CCC as we call it. We use a lot of CCC 720 (gram/liter) in winter wheat and winter barley. In winter barley we use etaphon as well.

For wheat:
1st App: at GS 21 (autumn) at 0.4 liters/ha for winter hardiness and tillering improvement.
2nd App at GS 25 (spring) at 0.5-0.6 litres/ha to improving tillering
3rd App at GS 31 or 32 at 0.6-0.8 litres/ha to shorten the wheat. At GS 31 when the wheat is thick and you do not want the additional smaller tillers to develop further. At GS 32 when the crop is thin and you want as many tillers as possible to make it to harvest.

The price for us is US $3.50 litre for Chinese CCC 720 g/litre product!
Kees Huizinga, Ukraine