December 3, 2013

Agronomist Notes

Hello Reader

I spent a few days last week attending the Bayer Crop Science Agronomy Summit in Banff, AB. There were 120 people in attendance and we discussed everything from fungicides to herbicides, seed technology, plant health and resistance strategies. I came away with a clearer picture on herbicide and disease resistance strategies for my clients and I’d like to thank Bayer for putting on a great event. The Banff Springs Hotel was a nice touch.

In this week’s issue, we’ll look at the improvement in timeliness CTF brings. Next, we’ll quickly review the impact of canola seed size and then we’ll see where our yield disappears the moment the seed is put in the ground. We’ll finish with technical grain market news.

Have a great week.

Photo: Not a bad view from my room the Banff Springs Hotel. SL

CTF is built for weather extremes

From Australia to Alberta

One of the major benefits of controlled traffic farming is the ability to improve timeliness of all farming applications. Permanent traffic lanes embedded within CTF fields provide a solid platform to run equipment across, even in the wettest conditions. In our climate, rainfall is the single largest climatic event that can bring every action to a grinding halt. How do you put a value on the economic loss caused by delayed seeding, herbicide and fungicide applications and harvest? Anyway you look at it, it’s a big number!

In 2010, a group of us from CTF Alberta travelled to Australia and witnessed one of the wettest harvests on record. At the time, rainfall totals were up to 16 inches within 30 days and harvest was only 25% complete. Combines were stuck, water was running across roads and fields were flooded. It was here that we experienced the true value of CTF and permanent tramlines. While most farmers were stuck or pulling each other out or simply not in the field, long time CTF farmer Robert Ruwoldt harvested 1,000 tonnes of canola in one week. How did he do it? CTF and permanent, hard packed tramlines kept his harvest equipment afloat while equipment in random traffic fields sank down to their axles.

Now, of course, we farm in Alberta, not Australia; we’re different, our soils are different and our climate is different. Or is it? This year, Craig Shaw and his farm manager Mike Sulzle experienced yet another very wet season, including devastating hail near Lacombe, AB. In 2011, Craig split a 160-ac field in half and implemented a 30ft CTF system on one side and continued random traffic on the other as part of a CTF Alberta research project. Well, the rain continued into harvest and guess what they experienced between the CTF side and the random traffic check? The photos above tell the story.

In the top photo you can see the New Holland combine stuck in the mud about 40 feet inside the random traffic side after a one-inch rainfall event. The combine was bogged down to the axles while attempting to harvest winter wheat. The photo below it shows Mike combining winter wheat on the CTF side with water still lying in the tramlines. They were able to continue harvesting on the CTF side because the permanent traffic lanes kept them afloat on solid ground.

CTF can generate huge advances in the timeliness of seeding, spraying and harvest applications. Permanent tramlines provide a means to continue applications in spite of wet weather, our biggest barrier to timeliness. When you watch CTF farmer’s like Robert and Craig put the crop in the bin while the neighbors hardly move a wheel, it makes you think twice about the value of CTF. Timing is everything. SL

Photo credits: Craig Shaw

Canola seed size impacts plant population

I came across an excellent photo on Twitter that brought attention to the issue of canola seed size and seedling mortality. Each year we plant between 550,000 to 750,000 seeds per acre based on the recommended rate of 4 to 5 lbs acre. We do this knowing that 40% to 50% of the seeds won’t emerge or form new plants leaving us with an optimal target of 8 to 10 plants ft2. So how are we losing 40% of our seeds?

The photo above shows a seed size comparison trial with 3 g/tkw seed size on the right and 5.5 g/tkw seed size on the left screened from the same seed lot. The 5.5 g/tkw was seed was 25% larger than the 3 g/tkw and almost 100% heavier. You can clearly see the poor emergence on the 3 g/tkw side compared to the 5.5 g/tkw side. Oddly enough, the left side was planted with 180,000 seeds versus 320,000 seeds on the right, which really amplifies the value of large seed sizes, something we already knew.

In Western Canada we purchase canola seed by the bag and it has a handy g/tkw reference number to help you calculate seeding rate. Unfortunately, studies have revealed how variable seed size can be inside of one 50 lb bag of canola so the number on the side of the bag is questionable. Researchers from Lacombe Research Station sifted a bag of InVigor 5440 canola with a 5/16ths sieve and weighed the various seed sizes. The TKW marked on the side of the bag was 5.19 grams. The results showed that 68.3% of the canola seed was 5.18 grams, 7.9% weighed 3.37 grams and 23.8% weighed a whopping 6.72 grams per TKW. (See chart above for detailed results.)

So the question is, if canola emergence is impacted by seed size, and seed size is highly variable inside of each bag, how do we know how many viable seeds we’re buying inside each bag of canola? Hybrid corn purchased from companies like Pioneer list how many seeds are in each bag of corn, not the weight of 1,000 kernels. Would our metering systems and air delivery systems do a better job if they were calibrated with like sized kernels? Are we purchasing seed that has no chance of survival regardless of how we place it in the ground? At $60 per acre in seed costs (and rising), it’s time we take a serious look at answering the tough questions. SL

Photo source: Rohan Brill. Graph data provided by Craig Chaw, Lacombe.

Closing the yield gap

Where do we focus our attention?

Last week I sat in on a great presentation by Dr. Wolfgang Thielert from Bayer Crop Science in Germany who discussed the impact of biotic and abiotic stress on yield. Now, before you’re eyes glaze over, here are a few take home points I think you should consider.

The chart you see above (better seen here) shows the world record yields for corn, wheat, soybeans, sorghum, oats, barley, potatoes and sugar beets. The green line outlines the average yield, the yellow line signifies the yield lost to biotic stress and the red line shows the yield loss due to abiotic stress. To put it clearly, 70% of crop yields are lost due to abiotic stress. Once you put that seed in the ground, 70% of its yield potential is lost. The list below shows why:

Abiotic Stress Biotic Stress
Wind Diseases
Cold/Frost Pests
Ag chemicals Bacteria
Soil Viruses
Dust Weeds
Salinity
Nutrients
Ozone
Drought/Water logging
Moisture/Rain
Sunlight
Gasses
Heat
Soil type

So where should we be focusing our attention? Although important, biotic stresses like weeds, disease and other pests make up a small amount of potential yield loss. Abiotic stresses like wind, salinity, soil type, heat and nutrients account for up to 70% of lost yield potential! I say that we should focus on building a system that reduces the amount of abiotic stress our crops endure each year but anyone could say that so here are a few practical building blocks to use:

Stress: Heat
Solution: Spread residue evenly to provide a thin layer across the soil surface to reflect light and keep soil cool. Hot soil temperatures have a greater impact on yield than hot ambient temperatures.

Stress: Ag Chemicals
Solution: Apply herbicides to a uniform crop at the proper growth stage by placing seed evenly.

Stress: Salinity
Solution: Apply proper tile drainage to reduce high water tables that bring salts to the surface and deposit on the surface once evaporated.

Stress: Nutrients
Solution: Soil test and design a strategy that balances both uptake and removal of nutrients with an aim to achieve above average yields.

Stress: Moisture/Rain
Solution: Control equipment traffic to improve soil structure and allow moisture to properly drain and hold moisture at depth.

If 70% of our yield potential is lost due to abiotic stress factors, perhaps we should shift our focus to include techniques that reduce abiotic stress. I’d say we’re doing fairly well controlling biotic stresses but the research shows how little they do impact yield. The next big push in plant genetics and farming systems will be to address abiotic stress. We've taken a few steps in this direction but it's time to pick up the pace. SL

Reference: Buchanan, Gruissem, Jones: Biochemistry and Molecular Biology of Plants American Society of Plant Physiologists, 2000