Some Good Dirt on DirtPosted in: Farming By John Dietz March 24 2015
Growers and scientists are developing a deeper understanding of what happens within soil that remains untouched by heavy equipment. What they’re learning is that undisturbed soil = more bacteria = higher yields. Here’s how it could work on your farm.
A small family farm in Haldimand County in southwest Ontario may hold the most striking example in Canada of what happens when cultivated land is allowed to return to its ‘natural’ condition.
Ninety years of regular plowing and field traffic ended for this 200-acre farm 20 years ago. Today, crops grown on this land are shattering yield records — and drawing attention to the importance of soil health.
Dean Glenney calls the system ‘fence-row farming’ and it dates back to a revelation he had on this farm as a
It was 1963 and Glenney was 12. His father had passed away two years earlier and Glenney was running the family’s dairy along with his mother.
While plowing beside a fence, his plow rolled over a foot of fence-row sod that
had not been disturbed in decades. It
was different, and burned a picture in
“I got off the tractor to look at this stuff,” Glenney recalls. “I had no idea that I was looking at old soil structure, but that picture stuck in my head.”
He understood then that the reason for tall corn, or other crops, in old fence rows was the nature of the soil below. “The first thing you see is that the corn in that fence row is two feet taller than anywhere else,” Glenney says. “It’s like turning over Prairie sod for the first time. The crops were phenomenal, and that stuck in my head.”
The impressive fence-row corn was one thing, but Glenney really knew he was onto something after he sold a 40-acre berry field to an experienced vegetable grower. Glenney had always used his rototiller to prepare the seedbed, narrow the berry rows and chop sweet corn.
“The new owner tried carrots. The crop looked great until it was time to dig. Then he found the carrots did a right-angle turn where they hit the hard pan,” Glenney says.
“I looked at those carrots and recalled my crops in the fence rows. I asked, how can I recreate that fence row for my corn? My notion was that if I planted exactly on the same spot every year, forever, eventually it would turn into a fence row — but there were lots of challenges with that notion,” he says.
About six frustrating years into the trial-and-error conversion that followed, one day a buzzer startled Glenney as he was combining corn. He had always dumped corn into a wagon at the end of the rows, before the hopper was full. He had never once heard this combine’s ‘bin-full’ alarm.
And he was about 300 feet from the end of the row.
“I got the local Pioneer rep to come over and do the weigh wagon thing. Man, it was 230-bushel corn!” Glenney says. “In Haldimand County, 130 bushels was normal. I was fertilizing and my plan was to get to 150-bushels. After I hit this 230-bushel mark, we didn’t tell anybody for a long time because we figured they wouldn’t believe us.”
He began talking openly about his ‘fence-row farming’ as a system five years later. In 2010, he won the Ontario Corn Yield Challenge sponsored by Pioneer. His fence-row land, with a modest rate of fertilizer, was producing more corn per acre than the very best, heavily fertilized, Ontario farmland.
This raised eyebrows.
Glenney’s plot-yield-per-acre in 2010 was 283 bushels. It hit 299 bushels in 2011, and 301 bushels in 2013. He still fertilizes for 150 bushels.
With those results, Glenney started taking the message of fence-row farming to a wider audience. Toward the end of 2011, he was in Montreal with two other Pioneer guest speakers, the U.S. soybean champion, Kip Cullers and Dr. George Lazarovits.
Lazarovits was new to his job as research director at London, Ontario-based A&L Canada, after working from 1977 to 2010 with Agriculture Canada researching the impact of soil-borne plant disease on crop production.
As research lead for one of the largest soils testing labs in Canada, he was intrigued by the fence-row farming idea. And be believed that something else must be going on in Glenney’s fields.
Soon, Lazarovits was soil testing in Glenney’s fields and the two began working on a research project together.
The soil tests, which were taken 60 days into the 2012 season, confirmed Lazarovits’ hunch. Corn in Glenney’s high-yield soil displayed a very different spectrum of microbial activity from corn in a nearby, low-yielding field.
Glenney’s corn only had seven bacteria families. The other corn had 26 families. However, the total bacterial population was 100 times larger on the Glenney sample.
Lazarovits also looked at nutrient uptake. He estimated 60 percent of the available nutrients had been taken up in
the conventional field at this point in the season.
In Glenney’s field, the roots had taken up 95 percent of the available nutrients.
The lab found a third surprise. Both fields had 10 to 12 percent of available phosphorus as the season started. This increased to about 18 percent during the season on the Glenney field. Across the road, in the conventional field, there was no noticeable change.
“The bacteria that have colonized the roots and plants are like super-bacteria that have increased the efficiency of the plant,” says Glenney. “There’s some symbiotic relationship going on. [A&L] is trying to figure a way to take these bacteria and inoculate the other field to see if they can create the same results, without taking
Similar Results in Alberta
Independently, in southern Alberta, a research agronomist was having similar thoughts about returning cultivated land to a ‘natural’ condition for conventional grains and oilseeds.
In 2010, Steve Larocque, a crop advisor and owner of the consultancy, Beyond Agronomy, started keeping equipment off his own 640-acre research farm near Three Hills in an attempt to improve soil health.
This year, he will complete the second three-year cycle with controlled traffic farming (CTF).
Larocque grows wheat, barley, canola, peas and faba beans. He has 12-inch rows and two-inch openers on a 20-year old modified Concord drill pulled by a modified vintage Steiger 4WD tractor. He uses RTK satellite navigation and auto-steer for precision guidance.
“Convincing my partners to implement a CTF system wasn’t easy, but asking them to take a 4WD drive and put it on singles was. They’ve since bought in and we haven’t looked back,” he says.
Larocque’s tractor, sprayer, air drill, air tank, side-dress nitrogen toolbar and combine all operate on tramlines with
120-inch centres. The compacted tramlines take one-sixth of his land base; the rest of the farm is off-limits to equipment.
“We use last year’s wheat stubble as an 18-inch fence line and seed right beside last year’s row,” he explains. “We seed so accurately beside the stubble because we’re using RTK, we run on tram lines and we used a modified three-inch offset hitch. Otherwise, the stubble would plug the drill in a heartbeat.”
The first benefit he saw was even emergence.
“You can get really even germination and emergence because you’ve got lots of background fertility beside last year’s rows, and because the moisture is always there beside the root ball from last year,” he says. “The ground is mellow, your temperature and moisture is more consistent and your openers flow really nice beside the old row. Dead centre between last year’s rows is the driest, hardest area of the field.”
Larocque is hoping for a yield bump soon, but he is very happy with the changes so far. “We’ve had five seasons with CTF and an offset hitch, and it’s exceptional — and massively overlooked,” he says. “When we aim for 30 plants per square foot, we likely have 28 show up quickly within a day or two of each other. On five and a
half inches of rain, we had soft wheat do 85 bushels an acre. And with an old Concord air tank with two-inch openers, we’re shaving 25 percent off our canola seeding rate.”
His new approach is being scaled up by a few clients, cautiously. He starts them at inter-row seeding. When ready, they add RTK for seeding beside last year’s rows. Then consider CTF.
He adds: “I can count on one hand the people who are fully converted to controlled traffic in Western Canada. You’ve got to go at least four to six years with a controlled traffic system before you really understand the nuances.”
Could Bacteria DNA Sequencing Change Ag?
Indeed, the nuances of soil health are complex. Scientists are going even deeper now to examine what’s going on with the genes and bacteria in soil.
One of the few facilities with the capacity to do this kind of high-resolution screening is at the University of Western Ontario, in London, not far from A&L Laboratories.
Last September, Lazarovits called the university to get some assistance with his investigation of the biome that is producing Glenney’s 300-bushel corn.
Gregory Gloor works in biochemistry at UWO’s Schulich School of Dentistry and Medicine. Using the latest technology, the lab can identify specific microbes and the nature of their activity in a population by detailed sequencing of DNA and RNA.
“From a single gram of soil, we get back tens to hundreds of millions of short-sequence tags,” says Gloor. “We process them into a table which gives us a count per sequence. This enables us to identify the organisms. And with a lot more effort, we can figure out what the organisms are doing.”
Samples are populated by hundreds to thousands of individual organisms. The DNA patterns serve to identify them, like a census reveals occupations and numbers from a general population.
Gloor delivered results of the first high-resolution screening of Glenney’s farm in late January. Several years and many more samples are likely to be required to determine if the same organisms are always found in high-yield plants.
Still, the lab found “very distinctive differences” in bacterial composition with samples from the same cultivar grown in a high-yield site (Glenney’s) and a low-yield site with conventional soil management, Gloor says. Corn at each site had consistent, distinct and different bacterial composition.
“The profiles between low-yield and high-yield sites are very distinct,” Gloor said. “You could not confuse one with
This provides evidence, but not proof, that bacteria are boosting Glenney’s corn performance.
One day in the next year or two, the UWO sequencing experts and the A&L expert microbiologists will collaborate to identify the functions that all the organisms are doing that together boost corn yields.
“It’s real collaboration,” says Gloor. “We’ll be asking, among these thousand functions that are really different on Farm A and Farm B, which are likely to be important for crop yield? Then we’ll step back a little and say, Which of these belong to the same bacterial groups? In the end we may select 10 functions to make one new probiotic product that is important to the plant.”
Until now, microbiology focused on microbes as pathogens. The emerging exploration is in ecosystem health, in high resolution.
“We may not care so much about who is in the soil, but more about what they are doing to improve crop and soil health,” Lazarovits says. “Once we know this, we will be able to better manage agricultural practices and shift gene populations from negative to a positive potential. This will put good bugs into the soil — and good bucks in your pockets.”
Lazarovits and Gloor are confident it will be possible to ‘build’ populations of yield-boosting friendly soil microorganisms by inoculating seed and soil.
The search that is beginning now won’t be easy or cheap, but it may change farming as we know it.
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