February 19, 2013

Agronomist Notes

Hello Reader

I’m writing this newsletter from 38,000 feet traveling 883 km/hr over the Pacific Ocean en route to Adelaide, AU. I’ll be writing from the road for the next two weeks and sharing about the farms we visit and what new systems and technology I come across. This week we’ll look again at our nitrogen side dress system and run the numbers to see how it stacks up. Next, I’ll provide you an update on our CTF Alberta project with link to information and reports. We’ll finish with technical grain market news.

Aussie Aussie Aussie, Oy’ Oy Oy!

Side dressing nitrogen in a controlled traffic farming system

The most common yet inefficient method of applying top dressed nitrogen is with a streamer bar or dribble band liquid UAN with the sprayer. This application method is inefficient because there is always a percentage lost to volatilization and even more to immobilization. What isn’t lost in the process is reliant on rainfall to wash the nitrogen into the soil to make available to plant roots.

The key to improving application efficiency is to side dress nitrogen, putting it directly into the ground, beside the roots and away from the surface where it can’t be tied up or lost. For Mitch, Sam and I, our controlled traffic system gives us the option of side dressing nitrogen between the rows, in-season with minimal to no crop damage at any stage of the growing season. To kick it up a notch, we’d plan on applying variable rate nitrogen on the go using GreenSeeker technology. We purchased a 6 sensor GreenSeeker demo unit for $22,000 in 2012. It plugs nicely into our Trimble FMX display.

The solution we’ve come up with is to purchase a 60-foot, FAST 8200 side dress toolbar with 1800-gallon tank, 20-inch coulters on 24-inch centres. The cost of the unit is $65,000 including assembly. The coulters can be adjusted anywhere on the 7x7-inch square tubing toolbar to adjust for our inter-row set up. The shanks on our Concord are not perfectly centred across the drill and two passes with our drill will have a specific pattern because of our offset hitch. In order to follow our unique pattern and stay between the rows, we’ll have to make adjustments to the spacing of the coulters.

The FAST 8200 can include up to a 2,100 gallon tank and as wide as 90 feet. I originally thought of using the high clearance sprayer with a unit like the Haggie. Have a look here. However, we’re already busy with the sprayer at tillering in cereals and bolting in canola. Adding another pass with the sprayer to side dress nitrogen wasn’t going to fit. That said, most people have a front wheel assist tractor hanging around and doing very little at that time of year. I thought it would be best to set up a tractor and side dress unit, which could side dress all day while the sprayer kept rolling on herbicides.

The total cost of the 60-foot FAST unit with GreenSeeker was $87,000. That’s a significant amount of money but this technology holds the potential to seriously improve nitrogen use efficiency, yield and protein. It can also help mitigate risk by allowing you to top up on nitrogen during the growing season when you know the crop is off to a good start rather than putting all that nitrogen up front. To kick it up another notch you add a GreenSeeker and you can start to address in-season variability and variable rate that nitrogen on the go.

Let’s look at the economics of owning the FAST 8200 60-foot toolbar on 24-inch centres and 1,800 gallon tank and a 6 sensor GreenSeeker. Budget $87,000 for the side dress system and assume 28-0-0 UAN is $0.73/lb with a side dress nitrogen application rate of 40 lbs/N/ac.

Steve’s quick math

40 lbs/N/ac as 28-0-0 × $0.73 lb = $29.20/ac
25% N loss from tie up and volatilization
FAST side dress unit: $87,000
25% efficiency gain × $29.20/ac = $7.30/ac

In this example, if we could gain a 25% increase in nitrogen uptake efficiency from side dressing nitrogen versus streaming UAN, we could generate a return on investment within three years on a 4,000 acre farm. This is solely based on nitrogen savings alone. That doesn't include yield, protein or quality gains from a reduction in lodging from the proper rate and timing of nitrogen.

The nitrogen side dress system would work really well in a CTF inter-row system like ours and the FAST side dress system fits in nicely with our precision platform. However, I would argue that anyone who can inter-row seed and run temporary tramlines could begin to side dress nitrogen. If you start adding up nitrogen savings, yield, protein and quality gains then side dressing could be the way of the future. I’d love to hear your thoughts on this, just reply to this email. SL

Results from CTFA Project, Year Two

We’ve completed year two in our three-year CTF project where four farms compare CTF to random traffic farming in side-by-side trials. We are farm number five but have yet to introduce a random traffic check. (It will happen in 2014, we promise, begrudgingly, for the greater good.) I’m happy to announce the initial results show between a $25.00 and $76.00 per acre benefit to CTF versus the traditional random traffic system. However, one of the four farms showed a decrease in revenue in CTF versus the check. The producer believes the side-by-side trial may be skewed because the check is in a better area of the field compared to the CTF side.

It’s hard to ignore the 5 to 10 bu/ac advantages in barley and 10 bu/ac advantage in CPS wheat with CTF. After seeing water infiltration rates triple in these fields, it’s not surprising to see such yield bumps in the CTF fields. Most plants do not tolerate wet feet for long periods, especially barley. The heavy rains in May-June led to temporary water logging, causing shallow root systems and denitrification. The CTF plots may have faired better due to their ability to move excess water away from the root zone and store it down below for access later on. I’ve seen this before in Australia with CTF outperforming random traffic fields in excessively wet years.

CTF is already performing well after two years of implementation. I believe it has the potential to take no-till farming to a new level. If you want to find out more about the results of the CTFA project and see notes and results from each site go to 2012 Plot Reports are now available online. SL

Peas seeded inter-row on CTF system, 2012. S.Larocque