April 16, 2013

Agronomist Notes

Hello Reader

It’s hard to believe that at this time last year we were planting when today most of us are staring at snow banks. The weekend storm brought anywhere between 2 and 10 inches of snow and with a cooler week ahead, we’re now looking at an early May start. We’ll roll with the punches and adjust seeding rates and crop types as the season demands to offset the later start.

In this issue of Beyond Agronomy News, we’ll look at controlling volunteer canola ahead of planting canola. Next, we’ll take a realistic look at seeding speed to give you some tips on how to nail down your ideal seeding speed. We’ll look at a strip till system from my recent farm tour and finish with technical grain market news.

Have a great week.

Photo: It rained again in flake form at the farm this past weekend. Our air drill has been covered in snow for six months and counting.

Controlling volunteer canola ahead of canola

The risk of volunteer canola is massive this year after heavy windstorms blowing swaths across the landscape last fall. Couple that with tighter canola rotations and volunteer canola pressure could be very high this spring.

The question becomes, how do I kill volunteer canola prior to seeding canola? There are three options available to producers, two registered and one not.

Option 1. CleanStart, $7.60/ac
Apply 15 ml/ac of carfentrazone (Gp 14) and ½ L/ac REL glyphosate (Gp 9). It can be applied pre-seed and post-seed just prior to emergence. IMPORTANT: It will not control cotyledon staged canola, only 1 to 3-leaf stage canola. The carfentrazone must come into contact with the growing point, which is next to impossible with a cotyledon stage canola. To improve performance a medium to fine droplet size is ideal with 10 gal/ac of water volume. Also, to improve performance, apply in temperatures above 8 degrees Celsius.

Option 2. Amitrol + ½ L/ac REL glyphosate, $11.00/ac
Apply 1.0 L/ac of Amitrol (Gp 11) with ½ L/ac REL of glyphosate (Gp 9). This product can only be applied as a pre-seed burn down and controls cotyledon to 4-leaf stage canola. Ideally, you would only wait a day to seed after application if targeting annual weeds. Amitrol works slowly, so don’t apply more than ½ L REL glyphosate per acre or it will reduce effectiveness of the Amitrol.

Option 3. Liberty 1L/ac, $7.00/ac
Apply 1 L/ac of Liberty as a pre-seed or post-seed application to hit cotyledon to 5 leaf canola. This is a cost effective option although it is NOT REGISTERED. You really need temps in the high teens or low 20’s with sunny days. Also, you need decent coverage so bumping water volumes to 7.5 L/ac would be better than sticking to 5 gal/ac. SL

Photo: S. Larocque

Speeding kills

Maximize seeding speed without sacrificing placement.

When it comes to small seeded crops like canola, research has shown that increasing seeding speed reduces yield and maturity. One could say the same thing about wheat and barley to a lesser extent. With a potentially narrow seeding window this year producers will be pushed to get things done faster. That means seeding speeds will increase at the expense of germination and emergence. So the question is how fast can we seed without sacrificing seed placement?

The key to fine tuning your seeding speed requires careful observation and helping hand. First, seeding speed is dependent on a number of factors: soil moisture, soil texture, seed size, opener style, and row spacing.

Each variable will alter the soils ability to flow around the opener and its ability to move out of the furrow and on to the next row. For example, in a loamy, dry soil with an older Dutch paired-row low draft openers on 10-inch spacing, I've seen significant soil throw at just 4.8 mph. Take the same opener and row spacing in a clay soil and you may not find the same result. The easiest way to find the sweet spot is to stick someone in the tractor, grab your quad and drive right along side of the drill to watch the soil flow real time. Have the operator speed up or slow down so the soil flows evenly across the opener and back into the furrow. Follow up with your trowel to measure the variability in seeding depth across the drill and you're set. You could also mount a GoPro camera on the shank as I've done and watch soil flow by reviewing the video.

To give you an example of soil flow, look at the soil around these CASE 800 precision openers at 4.8 mph (bottom) and 5.2 mph (top) in the photo above. The opener is 3/4 inches wide on 10-inch spacing so there's not much iron in the soil, yet look at the soil throw at 5.2 mph! In this situation with dry loamy soil, speeds over 5.2 mph resulted in poor seed placement. In wetter conditions the speed could have been increased a few points. Again, this is something you can only observe beside the drill.

If you find yourself rushed to get the job done this spring, be sure to take the time to find out how fast is too fast. Perhaps you can go faster than Steve's torturous, fail-safe 4.3 mph recommendation for canola. Maybe it's 4.8 or 5.0 mph. Maybe you'll stop buying new openers to fix your speeding problem. Or, maybe you'll discover you have the right openers and can grab one more gear. SL

Strip tilling on the Prairies

Banding fertilizer, managing residue & warming soil

On a recent farm tour we visited Garry MacLagan from Rolling Hills, AB who built his own strip till unit to manage residue, band fertilizer and warm soil prior to seeding sunflowers. Cold, wet soils with heavy residue can severely impact germination, emergence, maturity and yield, especially in crops like canola, sunflowers and corn. Strip till helps solve those issues by creating 6 to 8-inch wide strips of tilled soil 4 to 6 inches deep every 15 to 30 inches depending on your planter’s row spacing. I have to qualify that this technique helps dry and warm soils in the spring, which may not be suitable for drier areas on the Prairies.

Garry mounted Yetter strip till units on 20-inch centers to an old 7000 John Deere planter along with a tow-behind Flexi-coil tank. The 20-inch centers match the row spacing on his John Deere planter. Thirty-foot 7000 series John Deere planters can be picked up for roughly $10,000 or less with vacuum planter units attached. The Yetter strip till units that Garry bought were $1,200 each so all in he managed to build a strip till unit for just under $50,000 compared to the $90,000 to $150,00 price tag some of them fetch.

Blake Vince, fellow Nuffield Scholar and long-time strip tiller from southern Ontario, grows corn and soybeans. Here are his top ten tips for successful strip tillage:

Be patient for correct soil moisture.
Coulters are preferred for spring strips. Shanks could result in excessive smearing.
Shallow as possible in spring to provide desired seed bed.
Be prepared to roll or pack spring strips to conserve moisture if warm drying winds are an issue.
Have planter ready when strip tillage machine goes to field to conserve seed bed moisture.
Uniform distribution of fertilizer to prevent early seedling burn (low salt index fertilizer).
Planter attachments may no longer be required (trash whippers/row cleaners only).
Planter should be same number of rows as strip tillage machine.
RTK would allow 8-row strip tillage machine to match 16-row planter.
Fall zones may not always be highly visible. RTK gives repeatable accuracy and peace of mind in spring.

Blake says he would not be strip tilling without RTK. For him, the strength of the two-pass system lies in the ability to fall-apply fertilizer, and therefore improving springtime efficiency. He notes the temperature difference in the tilled strips can be 11 degrees C warmer compared to non-tilled soil.

In the end, I can see a modified strip till system that disturbs 6 to 8-inch wide strips by 2 to 3 inches deep on 15-inch centers for planters seeding canola in the moist areas of the Prairies. One of the biggest issues with canola germination, emergence, maturity and yield is poor residue management and cold soil temperatures. Perhaps a shallow strip till may be the answer to manage residue, band nitrogen and sulphur and warm the soil; all the things we’re looking for but don’t have the means to do outside of cultivating the entire field. I’ll definitely be watching for the results from Garry’s strip till unit to see if the technique is applicable in Western Canada. SL

Pictured above: Top, Garry MacLagan’s 7000 series planter toolbar. Middle, The Yetter strip till unit with coulters and shank. Bottom, Flexicoil tow behind air cart attached to toolbar. Source: S. Larocque

Readers Comment

Biological fungicides in canola, April 9th

One thing about Contans is keeping it cold while waiting for the right time to spray: it seems wives do not appreciate a couple hundred pounds of live bacteria resting on top of their steaks/chops in their freezers, without some warning. Coverage of the soil with the product is also very important - we can't expect something as small as a bacteria to amble one inch over to something the comparative size of Ayer's Rock and start munching at the base. I was told that half an inch should move it into the soil, onto the exposed sclerotia bodies on no-till ground quite easily. We have used it for 3 years, using the recommended rate you mentioned for the first year and then the 1/2 rate for subsequent years as a maintenance program, which should work well for the canola-wheat-canola guys who cannot seem to diversify further.

Also, UAP seems to bristle at the question of whether the sclerotia spores will blow in anyway from neighboring infected fields, and they show some data which appears to conclude that the level of infection decreases quite rapidly as you move away from the infected site, indicating that these spores are heavy, and cannot travel far by wind. (This is a bit like hybrid canola seed production; you have to have honey bees or alfalfa bees or both to take the pollen from the male bays to the female bays. The pollen is too heavy to be 'blown' to the female plants). I haven't found any evidence to support their claim.

Garry MacLagan, Rolling Hills, AB