May 7, 2014

Agronomist Notes

Hello Reader

Here we are May 7th and only a small fraction of farms have started seeding. Cold, wet, rain and snowy weather has hindered seeding progress across my territory. We’re sitting at less than 1% seeded for the area but on the positive side we have a full moisture profile in the top 24 inches.

Mitch and I should be in the field on Thursday setting up the drill to plant peas. I hope the weather holds and we can get this crop in the ground!

This week we’ll look at the impact of sprayer tracks on water infiltration rates. Next, we’ll take a brief but important look at farm safety this spring. Last, we’ll look at improving nitrogen use efficiency and planting efficiency. We’ll finish with technical grain market news.

Have a great week.

Photo: Peter Gamache and I time water infiltration rates in my wheat stubble. Photo source: Daryl Chubb

Agronomy

Minimizing damage caused by sprayer traffic

This week we’ve been working on water infiltration experiments to evaluate impact of sprayer tracks on water movement. As we know, sprayers are travelling across the fields at the wettest time of year and have the greatest potential to do the most damage to soil structure. To measure the impact of sprayer traffic this spring we used a water infiltration test to compare sprayer tracks versus outside sprayer tracks. The sprayer was a John Deere 4830 with 120-foot aluminum booms, and 650 mm tires.

Experiment:

One pass with JD 4830, 120ft booms, 650 mm (25.6 inch) tires
Soil type: 60%, 2:1 cracking clay soil with 4.5% OM
Three, 10-inch aluminum rings in spray track with 1-inch water per acre equivalent
Three, 10-inch aluminum rings outside sprayer tracks with 1-inch water per acre equivalent
Spray tracks: 12 minutes and no water movement
Outside spray tracks: 4.01 min, 1.45 min, 1.10 min

In this experiment, the water never did infiltrate into the sprayer tracks and would likely evaporate before it moved into the soil. The 650 mm tire is considered a floatation tire and yet it damaged the soil structure enough to prevent water infiltration. So, before a seed is put into the ground, 3% of this field will suffer a yield penalty from low water infiltration and a reduction in root growth.

One prevailing fact from the simple trial was that no matter how wide the tire, like a 650 mm floatation tire and one of the lighter sprayer footprints out there with the JD 4830 fitted with aluminum booms, damage to soil structure was severe. With SF2 guidance, the next few spray passes will widen the footprint even further due to a lack of repeatability. The math is simple on lost revenue so here’s my quick math.

Steve’s quick math
5% x $375/ac revenue average = $18.75/ac
30% yield reduction in sprayer tracks = $5.60/ac
4,000 ac x $5.60 = $22,400

First, if you don’t think sprayers have an impact on your bottom line, they do! What can you do about it? Run tramlines and match tire and axle widths to minimize the number of rows trampled from the sprayer. For example, if you could keep the sprayer running straight, the 650 mm flotation tires only trample two rows per pass with an air drill that has 2-inch openers on 12-inch spacing. In my experience, the outside rows beside the tram lines make up for the lost yield inside the trams. They have access to additional sunlight, nutrients and moisture so they often make up for the lost yield.

What this little infiltration experiment taught me was that sprayer track damage is more severe than I thought with floatation tires. Once you start doing the math on yield loss in the sprayer tracks, you might as well run tram lines and remove those rows altogether. Let the outside rows compensate for yield loss in the trams and give yourself a solid footprint to run the sprayer on all season long. SL

Photo: The sprayer track still holding water after about 11 minutes of it being poured with no sign of infiltration. S. Larocque

Host your safety meeting now

With a later than normal spring, producers and their staff are going to feel pushed to work longer, harder and faster to get the crop in the ground in a timely manner. That brings the risk of pushing the envelope on safety much higher than other springs. With that, there are a few things to keep in mind:

Don’t assume that your staff thinks the same way you do so be patient and listen to your employees when they do have a concern.
Encourage your staff to call you whenever they feel unsafe.
Everyone should know whom to call in case of an emergency.
Injuries happen when you take shortcuts in performing routine tasks, working while mentally or physically fatigued, or fail to follow safety guidelines.

For a list of fact sheets on farm safety go to Alberta Agriculture and Rural Development

Story in Ground Cover Magazine

I was recently featured in Australian Ground Cover Magazine, which summed up the topics I covered at the GRDC update conferences. I looked at CTF, managing biotic and abiotic stress, root heat temperatures, and nitrogen use efficiency. Have a look here, mate.

Combining logistics with N use efficiency

When it comes to logistics during planting, one of the biggest bottlenecks is the downtime created by handling large volumes of seed and fertilizer. Each year, farms typically apply between 250 to 400 lbs/ac of fertilizer and roughly 120 to 150 lbs/ac of seed in a direct seeding system. This creates a lot of downtime as you slow down to stop, crawl up ladders, open lids, swing out augers, back up trucks and fill every 1.5 to 2.5 hrs. The bulk of that product is nitrogen and the real holdup in the system.

In 2013, we developed an inter-row side dress nitrogen system that helped us remove a large portion of the nitrogen applied at planting, and apply it at the correct time in-season. This freed up space in the air cart, which reduced downtime during fills and allowed us to spend more time putting seed in the ground. In a late start scenario like this year, having a flexible system that reduces downtime relieves a lot of stress.

Here’s an example of how we increased our efficiency at planting.

Steve’s quick math
Air cart capacity is 6 tonnes or 230 bushels
Old system: 300 lbs/ac fertilizer, 140 lbs/ac seed = 30 ac/fill
New: 190 lbs/ac fertilizer, 140 lbs/ac seed = 40 ac/fill
Increase in efficiency = 33%

Example:
Air cart capacity is 11 tonnes or 430 bushels
Old system: 300 lbs/ac fertilizer, 140 lbs/ac seed = 53 ac/fill
New: 190 lbs/ac fertilizer, 140 lbs/ac seed = 69 ac/fill

The additional cost of our side dress toolbar is $3.00 an acre to run and operate plus the additional cost of having 40% of your nitrogen applied as UAN 28-0-0 for a total of $7.30 per acre. The added cost will be more than offset by the yield gains realized from properly timed nitrogen in-season. For example, just prior to bolting in canola and GS30 (stem elongation) in wheat. In my experience, barley does not require a split app in our climate, all up front at seeding works well.

The late spring has everyone rethinking their efficiencies at planting and unfortunately, placing all of your nitrogen needs in the spring decreases both planting efficiency and nitrogen use efficiency. The two-pass system with the side dress toolbar is low disturbance, allows you to adjust N rates based on the season and frees up precious air cart space to increase acres per fill. The side dress nitrogen strategy is making a lot of sense for us this year. It’s time to evaluate our nitrogen application systems. SL

Photo credit: S. Larocque

Beyond Agronomy Apps

Tank Mix & Rainfastness Guide

This tank mix app, built for Western Canadian farmers, answers the everyday questions about herbicide rainfastness and the proper order to tank mix herbicides.

Apple or Android

Seeding Rate Calculator

An app designed to help you calculate how much seed is needed to produce a desired plant population when calibrating your seeder.

Apple or Android

Air Cart Maximizer

The air cart maximizer quickly calculates the maximum number of acres per fill based the size of each compartment in your air cart and the desired fertilizer and seeding rates. The app indicates which compartments should be dedicated to seed or fertilizer and how much product to deliver out of each to achieve the greatest number of acres per fill every time.

Apple or Android