July 9, 2013

Agronomist Notes

Hello Reader

Crops are advancing quickly after the warmer temperatures last week. The high humidity and hot temperatures brought on a wicked hail storm that ripped through a narrow band in our area. The photo shows a narrow band of hail lying on the ground the day after the storm taken by a Jazz airline pilot enroute to Calgary.

This week we’ll look at a revolutionary way to apply nitrogen in narrow row cereals and oilseeds. Next, we’ll give you some tips on assessing hail damage in canola after the recent storms and we’ll look at the ins and outs of stripe rust control and prepare you for wheat midge scouting. Last, we’ll take a quick look at applying high rates of glyphosate on RR canola. We’ll finish with technical grain market news.

Photo: Narrow band of hail left on the ground a day after last Saturday’s storm. Cpt. Daryl Frank, Jazz Aviation

Crop Staging

(Calgary to Drumheller to Three Hills)

Seeded    May 1-7 May 8-15 May 15-22
Wheat      flowering                heads emerging flag leaf
Canola     60% bloom             50% bloom 30% bloom
Barley      heads emerged      heads emerging flag leaf
Peas        30% bloom             20% bloom 10% bloom

Steve's tips & tricks of the week

Follow me on Twitter for in-season updates @BeyondAgronomy

Look for patchy head emergence to pin point air drill issues or residue issues. Measure out patterns and make corrections before next year.
The conditions for disease (host-pathogen-environment) have all lined up and disease risk is high for all crops.
Stripe rust has arrived in our area so fungicide in wheat is a must.
Start sweeping early flowering canola for cabbage seedpod weevils.
Start scouting in the late evenings for wheat midge in wheat that has not flowered yet. SL

CTF tour Thursday, July 11th, 1:00 pm

Please join us!

We are hosting a field day with CTF Alberta Thursday, July 11th from 1pm - 4pm at our farm NW of Morrin, AB.

When: 1:00 PM to 4:00 PM
Where: One mile west of Morrin, AB on HWY 27 and 1.5 miles north on RR 20-4 (N 51 40.234 and W 112 47.543) Google map

What:
1:00pm – Sign in
1:30pm – Introductions and CTFA project
1:45pm – Steve Larocque, update on 4th year CTF
2:30pm – Nitrogen side dress toolbar (FAST 8100 toolbar)
2:45pm – Crop walk and UAV demo flight (JZ Aerial)
4:00pm – Wrap-up discussion (plant growth regulators, split app nitrogen)

There is no charge for the event. Refreshments will be provided. Three Soil & Water CEUs.

Side dressing nitrogen in narrow row crops

Improving nitrogen use efficiency

In an effort to improve nitrogen use efficiency, top dressing liquid nitrogen has become very popular. Applying all the nitrogen needs at seeding works, but it leads to lodging, excessive straw, N losses in wet areas and leaching in lighter soils. Top dressing nitrogen through streamer nozzles (6 stream or 4 stream) using UAN (28-0-0) works really well but only when followed by rain to take the product to the roots. I believed there had to be a way to avoid the losses that come with applying nitrogen on the surface and the reliance on rainfall to generate a response. Well, there is indeed a method to do just that. We recently brought together a concept used in row crop corn called side dressing nitrogen and tailored the technique to our CTF system on 12-inch row wheat.

Side dressing nitrogen is a technique used in the corn-belt where producers use coulter s to inject nitrogen (UAN or NH3) beside each corn row. Applying nitrogen closer to peak demand reduces the risk of loss, increases yield and ensures nitrogen is available just prior to peak demand and without the rain requirement. Mitch and I purchased a FAST 8100 60-foot toolbar with 20-inch coulters spaced every 24 inches and a 1,800 gallon tank. The axle spacing is 120 inches or 10 feet, which matches our tram lines and other implements. We applied liquid nitrogen (28-0-0) between two rows every two feet like a mid-row band concept.

See the toolbar in action on early flag leaf wheat here.

This year we trialed 60 acres in two wheat fields applying 20 gal/ac (60 N/ac) at 7 mph, 3 inches deep at early flag leaf. We would have preferred to apply the nitrogen a little earlier at GS 31 or the start of stem elongation but the unassembled toolbar was dropped in our lap in early June. It was everything we could do to get it assembled (and slightly modified) before the application window closed. The optimal timing to apply nitrogen begins at stem elongation and ends around GS32 if yield is the goal. Nitrogen applied after flag leaf will be directed toward protein. With the right protein premiums, side dressing may be a great fit to apply nitrogen late in the season without crop damage.

The cost of the 60-foot toolbar was $70,000, including a 1,800 gallon tank and 30 coulter units. When you compare the cost of streamer nozzles at about $20.00 a piece or $1,500 to fit a 120-foot boom it sounds ridiculously expensive. That said, a 3,000 acre farm top dressing 30 lbs/N/ac with no rain after application may see little to no response. At $0.70 lb/N or $21.00 ac, that’s $63,000.00 in nitrogen laying on the surface doing little to no good. The toolbar would almost be paid for in that scenario. Then factor in the yield loss from poor performance or the yield gain from proper nitrogen placement with the toolbar and the side dress unit begins to make sense.

For those who don’t have a CTF system, the toolbar will still work provided you have nailed down inter-row seeding and have RTK guidance. The 60-foot toolbar only requires a 150 hp tractor to pull the unit and has little draft. You can run duals to reduce compaction and apply nitrogen at 5-leaf, 2 tiller when the crop can still bounce back from wheel traffic. If you upgrade to the 2,400 gallon tank you can side dress 240 ac/fill with one man and one trailer. Most top dress application rates are around 10 gal/ac or 30 lbs/N/ac. At 7-10 mph on 60-foot you’re running roughly 60 acre per hour. That’s 4 hours between fills so you can get some work done in a day.

Field notes:

Always measure width! Toolbar was actually 58 feet wide not 60 feet wide so we needed to attach extensions to bring it out to 59 feet wide. One-foot of underlap on each side gave us a two-foot guess row to match our two-foot spacing on the coulters.
Gauge wheels, 8-inches wide ride perfectly between the 12-inch rows and don’t trample crop.
Gauge wheels ride nicely on tram lines and entire unit holds firm on tram lines with very little movement side to side.
A 30-foot drill with offset hitch makes it difficult to space coulters evenly on 60-foot toolbar because you have two different patterns on 60 ft. Travelling south on north seeded swath forces two gauge wheels to ride on crop which is not ideal.
We will travel north on two swaths and south on two swaths to match the coulter spacing and gauge wheels so they ride between the rows on every pass.

At the end of the day, it’s CTF and inter-row seeding that really makes this system perform. The ability to apply nitrogen at any stage without damaging the crop swings open the doors of opportunity. Now we’re thinking about spacing nozzles on 12-inch spacing to apply fungicides on top of the rows with 80 degree nozzles (Thank you, Mr. Ruwoldt). We could apply herbicides between the rows to reduce herbicide application on our crops which causes undue stress. We could sow cover crops in-season while side dressing nitrogen and do two things at once. The possibilities are endless. I’d say we’ve only just begun with precision ag! SL

Photo: Our Fast 8100 toolbar side dressing wheat at 7mph. S. Larocque

Hail damage in canola

What have you lost?

Yield loss in canola is always difficult to estimate when hail hits during flowering, especially when you're trying to come up with a fair estimate with the hail adjuster. Here are some facts to give you an idea of what to expect for crop loss after hail:

Any leaf area destroyed will result in yield loss.
Seed yield losses in canola are approximately 25% of leaf area lost. If leaf defoliation is 50%, then yield loss would be approximately 12.5%.
Seed yield loss will depend on both percent leaves and branches lost. For example, if canola has 60% lost branches 7 days into flowering, seed yield loss is estimated at 18%, whereas 21 days into flowering, yield loss would be an estimated 60%.
If hail strikes late, such as during pod filling or ripening, plant recovery is not possible. The time needed to develop new growth, flowers and mature is limited before a killing frost.
If injury occurs at the ripening stage then it depends directly on the loss of branches, individual pods and seed knocked out of pods. Severe hail losses have occurred in canola swaths.

Source: Canola Council of Canada

Wheat Midge Identification, Damage & Control

With wheat beginning to head out, now is the time to prepare for Wheat Midge scouting. We’re nearing the threshold growing degree day number where they begin to emerge. These small bugs are about half the size of a mosquito and bright orange. They lay eggs in the wheat head and the larvae will then feed on the wheat kernels.

Damage Potential
One midge per 4-5 wheat heads can decrease yield around 15%. They can also reduce the grade of your wheat. If there is more than one midge per 8-10 wheat heads there is a risk of a reduced grade. The Canadian Grain Commission limits midge damage in No. 1 CWRS wheat to 2% and 8% in No.2. In durum the tolerances are similar.

Scouting
Adults appear in late June and early July. Wheat fields should be scouted regularly between heading and flowering. Scout in the evenings, from about 8-10 pm, when the temperature is around 15 degrees Celsius and there is no or very light winds. Also, scout four or five places in the field for a more accurate count.

Threshold
One adult midge per four or five wheat heads is usually enough to warrant control measures.

Control
Cygon™, Lagon™, Lorsban 4E™, Nufos™ and Pyrinex™ are all registered for use on wheat midge in wheat. Check the label for any other restrictions regarding the chemicals. For example Cygon™ and Lagon™ do not control the eggs, just the adults. Also, application in the evenings are most effective. Check the label for application timing.
Cost: Lorsban: $8.40 acre + $8.50 ac/aerial application = $16.90/acre

Considerations for Control
Late evening or early morning are the best times to control the adults, as the females are most active in cool night time temperatures (but above 15 degrees Celsius or 59 degrees Fahrenheit) and when the wind is less than 10 km/hr (6 mph). Also, good coverage is critical for control if your chemical controls eggs as well; make sure the water volume is adequate. Optimal control happens when 70% of the crop is in the heading to flower stage. If 30-60% of the crop is flowering then it needs to be sprayed immediately to have good control on the wheat midge. If 80% of the crop is flowering then control is not recommended as the window has passed and the midge damage has already started. Spraying therefore should be done early to protect the main stem and first tiller, as this is where most of the yield potential of the crop is.

Wheat Midge Forecast Maps
Midge emergence can be modeled using accumulated temperature calculations called Growing Degree Day (GDD). Data provided by Agriculture & AgriFood Canada (AAFC), Saskatoon suggest using a base temperature of 5°C for predicting midge emergence patterns using accumulated GDDs. Thresholds for combined emergence of male and female midge are:
10% emergence     693 (±39) GDD
50% emergence     784 (±38) GDD
90% emergence     874 (±41) GDD

As of July 7th in the Calgary corridor we are at 653 GDD.
Wheat Midge Information
Alberta Midge Forecast map
Prairie Midge Emergence maps

Photo source: Saskatchewan Agriculture

Stripe rust identification & control

The presence of stripe rust has increased over the last week in my territory. This is significant because wheat crops have just started into head emergence, which leaves a great deal of time for stripe rust to infect leaves and reduce yield. If you haven’t applied fungicide already, do not hesitate at this point.

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.

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 prior to watery ripe stage. Fungicide treatments made past the watery ripe stage rarely provide an economical benefit.

Fungicide Options
Acapela: (picoxystrobin) 192 ml/ac, $10.90/ac
Caramba: (metconazole) 283 ml/ac, $10.95/ac
Fuse: (tebuconazole) 118 ml/ac + 0.125% v/v Agral 90, $12.00/ac
Folicur EW: (tebuconazole) 200 ml/ac, $11.85/ac
Headline: (pyraclostrobin) 160 ml/ac, $14.40/ac
Prosaro: (tebuconazole + prothioconazole) 320 ml/ac, $17.10/ac
Quilt: (propiconazole + azoxystrobin) 400 ml/ac, $11.80/ac

The most effective fungicides on the market for control of stripe rust are Folicur EW, Fuse, Prosaro, Quilt, Headline and Twinline.
Stripe Rust Tolerance Ratings (Scroll down to page 5 for hard red spring varieties and look for the stripe rust column for ratings.)

Photo source: Daryl Chubb, July 2013

Effects of high rates of glyphosate on RR canola

Each year I get asked how much glyphosate we can apply to canola in one shot to control difficult weeds like Canada thistle, big buckwheat or cleavers. Well, the easy answer is, it depends.

The label states you can apply no more than 1 L/ac REL to RR canola in one season. Monsanto's research suggests that producers who apply rates higher than 1 L/ac REL or past the 6 leaf stage will reduce yield by an average of 3 bu/ac. A three bushel loss is hard to see clearly unless you have a check in place. Micheal Wollman sent a picture over Twitter, which shows the delay in maturity comparing 1 L/ac REL (right) to 0.5 L/ac REL. The delay is obvious. The yield loss at this point is unknown. Don’t push the envelope with glyphosate applications on RR canola.

The field notes are as follows:
Variety is 45H29. 0.5 L/ac was applied at 4-5 leaf stage and ran out on one pass, then it rained. He came back three days later and applied another 0.5 L/ac on the same pass to equal 1 L/ac. The canola on the left had only one application of 0.5 L/ac. SL

Poor drainage killing barley yields

Is compaction costing you?

Everywhere I drive there are pale yellow barley fields stressed out from the 8-10 inches of rain we’ve received since planting. Barley is especially sensitive to low oxygen environments caused by saturated soil. Quenten Knight from Precision Agronomics in Western Australia sent me an interesting photo recently showing the effects of compaction on barley in CTF. The photo on top shows the pale yellow barley in the tramlines after 12 inches of rain in sandy soil. The photo on the bottom is barley field near my place after 8 inches of rain on heavy clay soil.

Soil compaction is an issue in Western Canada and is the root cause of poor drainage in many areas across all soil types. Notice the healthy green barley crop between the tramlines in the top photo. Removing soil compaction and subsequent water logging can mean the difference between an excellent barley crop and a poor one. In fact, in our CTF Alberta project the greatest response occured last year in barley at a 10% yield increase after just one year in CTF. Once again the spring was wet, soils were water logged and the CTF plots allowed water to infiltrate quickly and allow the barley to thrive.

After just two years of CTF in our cooperator plots we’ve tripled water infiltration rates. Keeping excessive water away from the root zone is a key benefit of CTF. CTF helps reduce denitrification, increase nutrient absorption, reduce stress, increase soil carbon dioxide and oxygen so plants and soil biology can thrive. All this from removing random wheel traffic and moving to CTF. Wet/dry and freeze/thaw cycles will repair soil compaction quickly but only if you stop driving over the soil and allowing it time to repair. I’ll leave you with this. Take a look at the photo above and the yellow barley growing in the tramlines. Look at the healthy green barley growing in between the tramlines. The only difference between the two is wheel traffic. CTF pays. SL

Photo source: (top) Quenten Knight, (bottom) Steve Larocque