Monday, 15 August 2011

The Burly Boys

"The Burly Boys" was Neil Dennis's nickname for the team of USDA employees located at Burleigh County, North Dakota. Specifically, they work for the Natural Resources Conservation Service, or NRCS for short, with Jay Fuhrer heading up the team. They are world famous for their work in advising farmers and growers about how best to improve their soil resource. (Incidentally, Gabe Brown also sits on the district board of NRCS).

When I was researching soils for my forthcoming trip, Jay's name kept on cropping up, so frequently that in the end I decided I couldn't ignore it and had to go and meet the man.

What a stroke of luck!

Jay met us in the middle of a 7' tall field of corn (maize) - as you do - on Gabe Brown's farm and after admiring the health of Gabe's crop, he took Ray (a South Dakotan farmer who'd also visited Gabe that day to pick his brains, free of charge) and me to his office in Bismarck then onto Menoken Farm. This was at 2.30pm on a Friday afternoon and it is a measure of the man's passion for his subject that he was still with us after 7pm that night.

At his office, after meeting some other members of his team, Jay explained the importance of glomalin, the glues created by the soil organisms that creates aggregates and peds (ie smaller and larger 'clods' of soil). In a soil that is cultivated, little or no glomalin is formed. This is because the physical turning and mixing of the soil kills many of the microorganisms, smashes any structures they've been forming and lets in air which oxidises any organic matter that was present.

In fact, the only way to retain structure in a cultivated soil is to keep cultivating it. Man has to keep 'fluffing it up' with heavier and larger machines to simulate a good soil structure and thus allow the roots, and water etc to infiltrate. It's a vicious circle from which it's difficult to escape.

In a no-till or direct drill system, soil structure is formed by these glomalins holding, or glueing, each mineral particle to its neighbour. The biological activity that secretes these glomalins also creates airspaces; humus in the soil absorbs water; organic matter feeds these microorganisms. The result, once the biological activity restarts (and a conventionally tilled soil can be pretty much void of such activity and can take several years to start to recover) is that soils naturally form a well aerated, well structured shape which holds onto water and nutrients and yet is free draining too.

Jay used the 'Soil Slake Test' and 'Soil Infiltration Test' to demonstrate the difference between the two soils. (Unfortunately, I managed to forget my camera, but have found an almost identical test on youtube being demonstrated by someone else, which is attached as follows):

A Slake and infiltration test similar to the one performed by Jay Fuhrer. The major difference was that, for the slake test, Jay used three soils: A conventionally tilled soil, a no-till soil and a no-till soil that had also had animals grazing on there some time in the recent past.

The biological activity - and hence the soil's ability to hold together - was even greater in the soil which had animals grazing on it. The title of my Nuffield study "Mob grazed cattle and their potential to be the perfect arable break crop" was chosen because I have long suspected that livestock are the vital missing ingredient on all-arable farms. Jay's experiment (and the visit to Menoken Farm) demonstrated that this is indeed the case.

Jay then took us to Menoken Farm.

Menoken Farm was purchased by NRCS a few years ago as an experimental farm in which to practice what the NRCS team are preaching. Jay has been experimenting with cover crops, animal impact, mixed cropping, compost and compost teas, no till, no fertiliser, no fungicides, in fact a whole range of different things.

As Jay explained, it's all about putting carbon back into the soil. He says soil is like a bank, you must balance your withdrawals (of carbon) with your deposits. Unfortunately, for decades, farmers have been withdrawing carbon from the soil and are now totally reliant on artificial inputs to grow their crops. This is unsustainable in the medium to long term, being heavily reliant on oil and diminishing natural resources.

We need to learn how to put something back into the soil. Cover crops, and livestock, both do this very efficiently.

At Menoken Farm, Jay had a range of experiments underway. He was growing a mix of cover crops and / or cash crops. His intention was to try to find how quickly the land healed itself (with the cover crop designed to put back carbon in the soil; the animal impact designed to stimulate biological activity) and how many 'withdrawals' a farmer could make (ie growing cash crops) before more healing cover crops were needed.

Jay doesn't go anywhere without his trusty spade. Very quickly, he was digging samples from the ground, showing the difference between soils with no organic matter added and soils with just one year's cover crop.

Now the soil at Menoken was basically sand. On the untreated land, it was a pale grey colour, and fell apart at the slightest touch. There was no carbon and hence no glomalin and hence, no structure to it. Alongside it, the soil that had been cover cropped/grazed for a year was darker in colour. It was starting to hold together too, not terribly well but noticeably better than the untreated soils. And this was after just one year.

On land that had been fed and undisturbed for longer, the peds (clods) were stronger, the soil darker in colour. He was also finding that, as the soil health improved, residues broke down quicker. (I'll expand on this in my next blog).

For anyone who's interested in the subject, I suggest they read Burleigh County's Soil Conservation District Website ( where there's some really valuable information.

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