Thursday, 22 November 2012

The Journey's ended... the journey's just beginning!

My Nuffield Scholarship travels are finally finished, my report is written and in two days time I make my presentation at the Annual Nuffield Conference, held this year in Stratford upon Avon.

I would like to thank all those who have helped me with my scholarship. There are many people around the globe who acted as marvellous hosts, informing me and making me feel really welcome. I will be writing to each of them individually, but in the meantime may I issue a public thank you to you all.

If anyone's interested in reading the fruits of my labour, my report can be found here:

My plan now is to form a custom grazing business. I provide the cows and the labour, whilst owners and managers of arable farms provide the land and the crops. I get access to land, arable farmers get access to more productive land! This way, we can see cattle reintegrated into the arable rotation and we can start to rebuild the world's soils.

Thursday, 12 July 2012

Swimming in Grass

Can cattle be mob-grazed when heavy clay soils are saturated? I was hoping not to have to find out until winter, however here in the UK, during the summer of 2012, we're enduring the wettest spell in recorded history! The ground is completely waterlogged; every time it rains there are rivulets running down the road as the ground cannot absorb any more water (and it has rained pretty much every day since the beginning of April!); cattle turn land into a quagmire within hours and it is wet, wet, wet!

To say it has been a challenge is an understatement. However, to answer my own question, yes, cattle can be mob-grazed on saturated heavy clay soils. Management practices do have to be adapted, and it's not always pretty. Here are a few of the things I have learned during this monsoon season:
  • Ensure the forage is very mature - mature forage means there's a lot of material between your cattle's hooves and the delicate soil. This provides a significant amount of protection for the soil
  • Don't overgraze - be prepared to waste more forage than normal. Once the cattle get hungry, they start to hunt around the pasture. This increases trampling and poaching massively and accelerates potential soil erosion and pasture damage
  • Give the cattle a larger area than normal - the majority of the most badly poached areas here were on the first strip after they've entered a new paddock. They are completely confined onto it and cannot move anywhere else, so poaching risk increases
  • Move the cattle frequently - go and check them every few hours and if needs be, move them to a fresh parcel
  • If you're providing temporary laneways to your water, move these each day too, onto fresh grazing - once cattle have walked up and down a laneway for a day, it is at risk of becoming a mudbath. New laneways reduce this risk; the cattle graze their way slowly to the water
  • Make sure you give the pasture sufficient rest after a wet grazing - as long as you have not left the cows on the land for longer than a few hours, and definitely not longer than a whole day, the pasture should not be too damaged and the grasses will grow back
  • Offer straw if the forage is lush and rich in protein - I offered a few wedges of barley straw each day when the cattle were grazing a clover rich, high protein, wet pasture which hadn't had sun for several weeks (and so was low in sugars and energy). They cleaned it up with relish
What the wet weather has confirmed to me is that water is definitely the limiting factor here in the eastern half of the UK (we average c.650mm in a typical year here). Even without much decent sunlight and with lower than average temperatures, the grass has just kept on growing. We are, literally and metaphorically, swimming in grass this year!

A field that was heavily trampled during the recent wet weather. The strip on the left was the first part of the field the cows entered onto and looks beyond repair

This is the same field a couple of weeks later, after regrowth has started. There are a few dead patches on the left where it was too heavily trampled but overall it is growing back very well. This field should have a total rest of c.85 days before it is regrazed, more than enough time for the grass plants to fully recover.

Cattle grazing a clover sward yesterday, 11th July 2012, during one of the wettest summers in recorded history. The damage to the land in the foreground is, hopefully, superficial but shows how wet the land is.

A close up of the clover-rich sward the cattle are grazing. It desperately needs some sun but is, I hope, full of protein. Certainly the cows' dung got slightly looser, though not as bad as I'd feared. The sward is very mature so there must be a significant amount of fibre within it.

Monday, 16 April 2012

Fresh Eyes

I have a theory that inheriting a farm or ranch is bad for the progress of the industry. Is this envy, because I'm not in line to take over a family business? Subconsciously, perhaps, but instead I prefer to think my theory has developed as I've made the following observations.

I have noticed that newcomers to farming take nothing at face value. They question everything and have no preconceptions about how and why things are done in a certain way. New Zealand agriculture is, I believe, an example of this on a national scale. In NZ, it is common to encourage new entrants into the industry, share farming in the dairy sector being a prime example. I am sure it is as a consequence of this that farming over there is much more innovative than here in the UK. We've copied a lot of their ideas from rotational grazing to the use of plate meters and the building of a grass wedge.

Conversely, inheriting a farm often means also inheriting the ideas and practices of the previous generation, especially when the 'inheritance' takes 30+ years to be fully completed and during this period the parents and grandparents are still, to a greater or lesser extent, involved and in control. Indeed, it is not unusual for a farmer to only become the decision maker on the demise of his parents, and he or she is often in their fifties, or older. They want a few years in charge before handing over the reins, consequently their children are in their fifties or older before they take charge, and so on and so on..... A fifty year old is likely to be a better businessman than a twenty year old but is also likely to be more conservative, therefore less willing to innovate and change his paradigms.

This is the reason I believe inheriting a farm is often bad for the progress of the industry.

George Brizuela-Kirk inherited a farm, a 1,000ha ranch in Paraguay. However, in his case, he didn't inherit the practices (good and bad) of his father. Instead, following graduation in Agriculture and Economics, he took himself off to Argentina and Australia to experience farming and life there. Further travels followed, he moved to the UK, completed an MBA and worked for various banks and financial institutions.

It was the death of his father that brought him back to Paraguay. He inherited one of his Father's ranches and a thousand head of cattle but was unencumbered by any historic practices. Indeed, he'd seen a wide variety of farming methods during his travels and also had an excellent financial and analytical take on business as a result of his subsequent career.

George amongst his herd of predominantly bos indicus cows, with a smattering of bos taurus blood. They were due to stay in this paddock for another four days before moving on. The amount of grass cover will improve as George continues to rotate and rest paddocks

Straight away, he could see the business had to change. Costs were too high with a labour force of eight people, produce was being taken and sold behind his back and environmentally the farm had been raped - soils were hungry and forage production was low.

Within a few months, George has started to turn things around. His workforce is now down to two men. He has subdivided the farm and has moved from set stocking to a rotational grazing system which is already starting to produce more grass. He also innovates, for example they have started collecting small coconuts - more the size of walnuts from this particular variety of palm tree - and grinding them down as a free source of high oil, protein rich feed for his fattening cattle. He knows of nobody else who does such a thing.

Milling coconuts for cattle feed. George hasn't yet had the feed analysed but so far the livestock weight gains seem good and the cattle have suffered no deleterious effects. From its texture it's easy to see it's high in oil and I'm intrigued to know what the analysis is.

As the farm is starting to grow more grass, George is focussing on increasing stocking rates. He's currently at 1 livestock unit per hectare, already considered above average for his region of Paraguay. His belief is, with the right grassland management, he will reach 4 LU's per hectare. This will be done solely through the use of cattle as a management tool, with no reseeding or additional costs incurred.

Currently, the farm is divided into 13 main paddocks (with a couple of these subdivided further). The cattle are on a 60-day rotation and looked in good condition at the end of a long drought and for the start of their winter period. Given that George has only been practicing this method of grazing since October last year, the progress he has made is remarkable.

However, we debated for some time which field the cattle should go into next. The dilemma was as follows:

The first field available had previously run out of drinking water during the drought, consequently the cattle hardly grazed it before they moved on to a new pasture. Because it was hardly touched, this field has a good quantity of grass in there, and it's all still very leafy and growing well. It had been rested, by default, for longer than any other field on the ranch.

The alternative field has much less grass on it. The green area wasn't too high and as a consequence I suspect a lot of the available sunlight was not being captured and turned into dry matter. It was only growing slowly because it hadn't yet got the leaf area to allow it to speed up growth, it was still in the early stages of the regrowth cycle.

One other factor to bear in mind: George estimated that there was probably another month to go before the ranch's grasses entered their winter dormancy period.

Which field would you graze?

George's instinct was to put the cattle into the field with the most grass. This would keep them occupied for up to a fortnight, allowing the second field, with much less ground cover, time to regrow.

I argued that instead he should put the cattle into the second paddock, the one with less grass. My reasoning was that the first field, with the greatest green area, was much more efficient at converting sunlight into dry matter. To make a financial analogy, you could say it was like having £140,000 deposited in a bank account which paid interest at 20%. The second field, with lower grass cover, was the equivalent of having £70,000 deposited in a bank account earning 4% interest.

By leaving the field earning you the greatest amount of interest/dry matter, the total growth on the farm will be maximised, even if the cattle have to be kept on a tight ration for a short period.

What that additional growth also demonstrated to me is that there is still huge scope for George to improve rest periods, by increasing stock density and having fewer groups of cattle, and that the rewards for achieving this are enormous.

Fortunately George, looking at the problem with fresh eyes, recognises this and despite the huge gains achieved in just over half a year, knows there is still a lot more to do. He has a clear vision of the future and, unencumbered with traditional practices, is drawing up his own road map to decide how to get there.

His inheritance looks to be in safe hands and I can't wait to return in a few years' time to see how much more progress George has made.

Wednesday, 11 April 2012

Factory Farming

I have a question for cattle farmers: What do you sell?

The chances are, your immediate answer would be something along the lines of "Store cattle!" or "Beef!" or "Fat cattle!"

Wrong. Try again.....

Hmmm, how about "Grass?"

Getting closer.....

Give up? The answer is sunlight! You are capturing light energy and converting it into a saleable form. It is as simple as that. You are virtually unique in this (maybe solar or hydro-electricity are almost there, though they always require some manufactured products before they can function).

Think about this for a minute. Sunlight is streaming down to earth. Every day, light radiation hits our farms. The more of this we can capture and convert into meat (or milk, or eggs or grains of wheat), and the less it costs us to capture it, the richer we become. It's a beautiful thought.

So how do we capture it efficiently? The answer lies in factory farming. In particular I am talking, in the case of a cattle farmer, about three separate but linked factories.

The first factory is the grass plant. This miracle of natural engineering has the ability to intercept the light shining down on to us. The more leaf area you have, up to a limit, the more sunlight gets converted into chemical energy. Chemical energy can be stored, used, sold. That is money!

The second factory is the soil. Grass needs nutrients from the soil. A living soil will be rich in all the nutrients needed by the plant. But, just like us, the living soil needs energy to stay alive. Where does that energy come from? Where else but the sun. We need to take some of the chemical energy now stored in the grass plants and give it to the living soil - the microorganisms, arthropods, nematodes, miccorhyzal fungae etc. So a significant part of the grass plant needs to be fed to the soil to keep it alive and healthy.

The third factory is the ruminant animal. The correct type of grazing animal has the ability to consume the grass and extract the energy from the grass, along with all the other nutrients that the grass plant extracted from the living soil. She will also, with her trampling, dung and urine, feed the living soil. This is a key point, part of the jigsaw puzzle that has been missing from many farms since the perfection of the haber-bosch process gave us artificial nitrogen.

I said earlier that the less it costs us to capture it, the richer we become. Let us imagine a perfect world for a minute and lets say we already own a large area of pasture and a herd of cows and a bull. The pasture intercepts all the sunlight that falls on that patch of earth and converts it into carbohydrate energy. Cost to the farmer? Nil.

We put the cows into the field. The cows graze some of the grass, trample the remainder to feed the soil and convert the energy they consume from the forage into growing calves. Cost to the farmer? Nil.

All of the heifer calves are kept to expand the herd, living off the stored energy and nutrients of the grass. Cost to the farmer? Nil. The remainder of the calves are fattened off the grass and are walked to the local abattoir (remember we're still in an imaginary perfect world without EU diktats etc!). The abattoir kills, butchers and sells them through its own shop to local people who walk from their homes to collect their meat. Total cost to the farmer? Nil

How much fossil fuel was consumed in this perfect-world farm? The answer is nil. I believe that livestock farming has the potential to be the only truly sustainable industry in the world. The energy source is free. The factories replenish themselves indefinitely at no cost to you and the end product is saleable for hard cash.

Now, real farmers will be throwing their hands up in horror at this stage. It's all very well in an imaginary world, they will say, but in the real world we have winter so we have to make straw to bed the cattle which uses fossil fuel. We also need to make silage, which uses fossil fuel. We then have to physically bed the cattle during the winter, which uses fossil fuel. We also have to feed them during the winter, which uses fossil fuel. We then have to muck them out, which uses fossil fuel. We have to spread the muck, which uses fossil fuel. Oh, and we have to build the sheds, which uses fossil fuel. And fossil fuel costs money, as does the labour needed to burn all this fossil fuel.


I am fortunate enough to have travelled to far-off places during my Nuffield studies. I have seen cattle ranchers in Missouri with 50"+ of rain and hard, cold winters who keep cattle outside all year round and don't own a shed or a tractor. They are a lot closer to the 'ideal world' than we in the UK are, and they are laughing at us.

I have seen cattle ranchers in Argentina, with 32"+ of rain a year and a temperate climate with intermittent winter frosts who keep cattle outside all year round. Despite the cover crops direct drilled for winter grazing, they too are a lot closer to the 'ideal world' than we are in the UK, and they are laughing at us.

Today, I visited a cattle rancher in Paraguay, farming is a sub-tropical area which receives 60"+ a year who keeps cattle outside all year round and doesn't own a shed or a tractor. He too is a lot closer to the 'ideal world' scenario than we are in the UK and he is laughing at us.

The cow can collect its own feed. The cow can spread its own dung. The cow has evolved over tens of thousands of years to live outside. During the past few decades, we have been sold pieces of a jigsaw that don't fit together. It is time to stand back, look at what makes money and what costs money and don't say 'it can't be done' but instead say 'how do I change?'

The Jigsaw Puzzle

Farming is a complex business. It is like completing a huge jigsaw, with myriad small pieces needing to be slotted into the correct place.

Traditionally, farmers receive the greatest number of pieces of their jigsaw from their parents and grandparents. Agricultural colleges may provide a few more, the internet, books and magazines still more. Often, along the way, parts of the jigsaw go missing. Maybe dad wasn't handed them in the first place, or he thought he'd try new and different pieces sold to him by a sales rep.

The problem is, the jigsaw is huge and is never really fully completed. Most farmers study the particular segment of the jigsaw they're working on. Few can stand back and look at the big picture. What should the jigsaw look like and which pieces are missing.

I have been pondering this question for a long time. As it's my blog, I'm going to indulge myself in my next post and articulate how I see the 'big picture'. It's really not complex at all.

Monday, 9 April 2012

Forage and Family

The hospitality and kindness of Argentinian people, especially towards a Brit visiting during the 30th anniversary of the start of the Malvinas/Falklands conflict, has been truly astounding. Diego invited me into his house to share lunch, Patricia did the same. Fernando went one better:

I happened to be visiting him on Maundy Thursday and Good Friday, the start of the holidays in this predominantly Catholic country. Not only was he on holiday, but he had a houseful of guests - his brother-in-law and wife had driven 700km from Patagonia to see them, and his mother-in-law was there for lunch too. Additionally it was his younger son's 18th birthday that day. Regardless of all this, he not only gave up both days to educate me in the ways of combined arable and livestock farming in the Pampa region, he also insisted I joined the extended family for lunch. During the course of the meal, they were shocked to discover I had yet to experience a true Asado, an Argentinian barbecue, and immediately made plans to hold one that evening.

Dressed for the outside - the autumn air in Southern Buenos Aires was getting a distinct chill - I was surprised to discover the meat was going to be cooked over the open fire in the main living room. A grill pan was placed to the side of a wood fire, the meat was placed on top and a thin layer of hot embers, scooped out of the fire was placed under neath it. These were replenished several times during the hour long cooking process and the resultant meat - ribs, flank and sausage - served with salt and a squeeze of lemon juice, was delicious.

On Friday morning we got down to more serious business - discussing forage for cows rather than for me! Fernando, in conjunction with the University of Buenos Aires, was using NASA satellite imagery to determine the dry matter production of the forage ground for all the group members. The system works like this: NASA makes the raw data available free of charge. This shows the level of green cover for a crop (green area index) and hence its ability to intercept sunlight.

Using meteorological records for the amount of photosynthetically active radiation received during each month, and by knowing the green area index (and hence the proportion of this sunlight intercepted by the crop), the amount of dry matter production can be calculated. Hence, on a field by field basis, Fernando knows by the 15th of the month following exactly how much forage the previous month yielded.

He has already worked out a grass budget for the farm, based on the dry matter requirements of the animals - 3% of body weight for fatteners and cows with calves at foot, falling to 2.5% (or less) for dry in-calf cows - and total cattle numbers in each category. This allows him to monitor production against expected usage and take early action should the two figures fall out of line for any reason.

The grass budget for one of the farms in the CREA Lamadrid group. The blue line is the forecast grass demand based on expected consumption. The green line is the forecast grass and forage production from all the pasture land on the farm. This farm shows quite a healthy surplus for the majority of the year, despite being expected to end the period with higher cattle numbers than it started with. Deferred grazing from the surplus times will be used to cover during the two points where demand outstrips supply

Another example of the meticulous planning and record keeping which has been a feature of my time in Argentina.

Sunday, 8 April 2012

The Answer?

I knew I was going to like Fernando as soon as I received his second email. Anyone who can crack a joke, in a foreign language, which makes a person from another culture laugh, is always likely to be a good person, and so it proved.

Fernando Pacin was the man in charge of 'CREA Lamadrid', another farmer-led discussion group which consisted of ten farmer-members who all divulged their performance figures to each other and tried to learn from each other's experiences. The fact that I even met him was down to the usual Nuffield-charmed luck that seems to make things happen.

I had posted on a farming forum in the UK that I was planning a trip to Argentina and asked if any other forum members had contacts out there. Very kindly, someone I didn't know responded, saying he'd attended a conference in New Zealand the previous year and had 'had a couple of beers' with an Argentinian. He had dug out the Argentinian's card and gave me the email address. I sent this unknown Argentinian an email on the strength of the word of an unknown Englishman. The particular Argentinian couldn't help, but very kindly forwarded my email to half-a-dozen of his contacts who he thought may be able to help my studies. Fernando was one of them!

Occasionally, in life, you have meetings that are totally inspirational. Your mind starts racing, ideas flash through your brain, it's hard to concentrate with so many thoughts churning round inside your head. The meeting with Fernando was one of these occasions.

Fernando has an amazing ability to convey complex principles - even in a foreign language - in a simple way, sketching diagrams in his notepad to illustrate his point. I have a sheaf of papers torn (with his permission) from his notebook to help me remember the details of everything he said.

We started the day (after Fernando had collected me from my hotel and brought me to his home) with a powerpoint presentation on the region and the performance of his CREA group of farmers. Straight away, the limits of my knowledge were being expanded. Fernando started talking about the evapotranspiration potential of crops compared to available water from precipitation, combined with soil water availability. Pasture land, for example, has an ETP of 1,300mm (+/- 100mm standard deviation [SD]). Soybean, which is only in the ground for four months, has an ETP of 500mm, likewise maize of 650mm and wheat of 400mm.

The rainfall for the area, though, is only 800mm (+/- 250mm SD). This, coupled with soil water availability of only 75mm (+/- 15mm SD) meant that water was the limiting factor in crop and pasture growth. Everything that could be done to conserve water was of benefit.

(Given that Eastern England only receives c.650-700mm of rainfall annually and also in light of the run of dry years we're currently experiencing, it made me wonder why we don't have such figures at our fingertips. Maybe some farmers do - maybe it's just me! I will investigate on my return to the UK!)

Fernando also talked about uplands and lowlands. These are not as we know them. The average land in his area is 170m above sea level. The uplands are c.1m higher and the lowlands are c.0.5m lower. This sounds like a ridiculously small variation to bother with but in actual fact it is a critical distinction. The lowlands collect rainfall which can take up to twelve days to drain away. This means that crops, alfalfa and improved grasses cannot survive there. Consequently, the 'lowlands' - small depressions in the flat landscape - are uncropped and grow tough, native grasses.

The uplands, however, are free draining and so are suitable for growing crops. This leads to a patchwork quilt-effect of cropped and uncropped areas across the land, with electric fences dividing the areas to allow cattle to graze.

Such topography encourages the keeping of livestock, as there is little alternative use for the lowlands. Fernando explained to me that the lowland area determined how many suckler cows were kept, stocking this area to capacity with cow-calf pairs. This in turn determined the number of fattening cattle they would have and so allowed the farmer to work out the area of upland needed to be put into pasture to fatten the weaned calves - in other words cows on the lowlands, fatteners on the better quality uplands.

Fernando talking to the farm manager of the first farm we visited (as he commented, the manager's of 'gaucho' blood). Fernando's son, Manuel, is standing to the right holding a cup of mate, the traditional shared drink of the area. The darker green area behind the group is the cropped land, whilst the lighter green area just below the horizon above the truck is a lowland area of native grasses

Cows tend to be around 400kg - much lighter than in the UK - and are almost exclusively either hereford or angus breeds. At weaning at c.6 months old, the calves weigh in at 180kg (45% of dam's weight). They graze cover crops, mainly of triticale, through the winter months (April to August) following weaning before moving on to pastures in spring (September), reaching finished condition by the time they are sold from January onwards. Average weight gain post weaning is c0.75-0.80kg/day meaning the calves weigh around 400kg at slaughter at c.16 months old - again much lighter than in the UK, though they were all of the right condition (ascertained by looking at them on the hoof and by examining the resultant beef in many restaurants during my trip!)

Some of the angus fatteners almost ready for sale. The windmill in the background pumps water for the livestock

The pasture was a mixture of alfalfa, cocksfoot (dactylis glomerata) and/or fescue. Although predominantly forage-fed, the fattening animals may get a little corn (maize corn) to keep them growing at the target speed - ideally not, but if forage quality is poor for whatever reason, the fatteners will be given extra corn.

The cows graze the 'rustic' grasses in the lowlands through the summer months which provide excellent quantities and quality of feed, most suited to sucklers. Following weaning in March, and during the winter months of April to July, the cows graze sorghum before moving back onto the lowland pastures as calving starts again in August.

Like all of the Argentinian farms I saw, it's a very simple system with no sheds, machinery or other equipment needed, save for fencing and a corral. The gauchoes ride round on horseback tending the cattle, which tend to be in groups of up to 350 head (considered to be the largest sized herd one man can look after).

Within the CREA group, the average size of the cattle enterprise was 40% of the total business for each of the ten farmer members, indicating that cattle were an important part of the enterprise mix. Part of the reason for this was, as in the UK, "corn up, horn down" and vice versa. The livestock often counterbalanced the cropping, making for a much more stable net profit when considered over the medium to long term. Of course, another driver was the existence of the 'lowlands' which weren't suited to crop production.

Another reason was the relative stability of livestock gross margins (gross margin figures are calculated after deducting all direct costs including labour costs directly apportioned to the enterprises). Fernando had detailed analyses of many aspects of the CREA group members' businesses. One of these was the swing in gross margins for different enterprises between good and bad years. Meat production had a gross margin swing of 56% whilst maize was the worst at 107% (reflecting the relatively shallow soils in the area, unsuited to maize's growth habits).

In an average year, the group would expect a gross margin of U$D234/ha from livestock whilst in a worst case scenario - a drought year where 40% of youngstock had to be finished in feedlots - the gross margin falls to U$D116/ha. By comparison, in the good years cropped land is much more profitable (gross margin of U$D438/ha) but in drought years the gross margin fell to just U$D8/ha. (Not surprisingly dairying showed the greatest gross margin of all, at U$D853/ha falling to U$D459/ha in a drought year, but the high levels of initial investment required plus the lack of a skilled dairymen in the area meant few farmers considered this option)

One of the very few dairy herds in the region. This one was only set up two years ago and took high levels of investment, met in part through the sale of a herd of suckler cows. Although the cows are holsteins, the system is predominantly forage based, all year round calving, with a flat-rate top up of concentrates in the parlour during the twice a day milking. I asked why, given the reliance on forage, they hadn't chosen a more suitable animal - a smaller New Zealand-type cow with maybe Friesian or Jersey bloodlines. The answer is that they are few and far between in the country and would be very hard to source, given that  the herd is only a couple of years old.

Financialy, the CREA group was showing an average return on capital over a 13-year period of 4.7% and an average return on tenants capital (before tax and drawings) of 21.8%. Net profit as a proportion of turnover averaged 29.6% and average annual turnover was 13% of all capital invested. Ignoring for a moment the high taxes and generally volatile politics in the country, these figures make such farms seem rather attractive investments.

Analysing the nitrogen balance of the farm was something else relatively new to me - a few years ago I did hear of one consultant who was doing this in the UK but as far as I know it is not a common calculation. The basic premise is that the nitrogen 'removed' from the enterprise is worked out (eg through corn or livestock sales), and the amount of nitrogen added to the system, either through applications of artificial N or through leguminous fixation of N are also calculated to give a net balance for the enterprise.

The nitrogen balance for the arable crops on a CREA group farm. The column on the left represents how much N was extracted and sold (crop sales). The next column is the artificial fertiliser added, followed by the N fixed by leguminous plants (in this case soybean). The right hand column is the net balance between the inputs and outputs.

This chart represents the farm's N balance. The deficit in N shown in the left hand column is from the arable crops, as per the first table. The central colum is the livestock, demonstrating the high levels of N-fixing alfalfa in the pastures used for the livestock enteprise. The right hand column shows the surplus N available within the rotation as a result of having a combination of cattle and crops.

The surfeit of nitrogen within the rotation as a whole has a real financial value. It is nitrogen locked up in the soil organic matter, available to plants under the right conditions and as a consequence, for the first two crops following pasture, no additional artifical nitrogen is applied.

Fernando had also analysed the net profitability of farming systems based on various different scenarios for upland (cropping ground) usage, including:
  1. Pasture land for 4 years followed by 4 years of cropping (ie 50% crops, 50% livestock)
  2. Pasture land for 4 years followed by 6 years of cropping
  3. Pasture land for 4 years followed by 8 years of cropping
  4. Pasture land for 4 years followed by 10 years of cropping
  5. Pasture land for 4 years followed by 12 years of cropping (ie 75% crops, 25% livestock)
  6. Permanent cropping on all land suitable for such use
The above chart shows the expected net margins achievable from the different cropping regimes before allowing for any reduced N usage.

This graph includes the value of the stored nitrogen within the margin. As can be seen, the far right column (continuous cropping) shows by far the worst net margin of all the options. With the higher returns from crops, but with the value of N from the livestock pastures, there is little to choose between having pasture for four years and crops for six years and having a 4yr:10yr mix of pastures and cropping.

What the above graphs do not take account of is the soil organic matter changes expected under the different pasture:cropping regimes. Fernando forecast the change in soil organic matter (from a 4% total Soil OM) over a 40-year period as follows:

Soil Organic Matter losses under the different cropping regimes (all crops being direct drilled). Unsurprisingly, the 4x4 regime, losses are least (forecast to fall by 1% from 4% Soil OM to 3.96% over the 40 year period. The permanent agriculture system has forecast losses of 11%, taking the soil OM down to just over 3.5% at the end of the 40 year period.

In a low rainfall region, preservation of soil organic can be critical, given its ability to improve water infiltration during rains then to hold onto the water, like a sponge, during dry periods. The above graph suggests aiming for a 4x4 or 4x6 mix of pasture and crops may be the most desirable for soil organic matter reasons.

None of the farms in the group were practicing mob grazing. Given its potential to build organic matter in the soils, as seen during my earlier travels, maybe the results could be even more impressive for farms where animals are included in the rotation.

Had I finally found the answer to my question of "Are mob grazed cattle the perfect arable break crop?". I suspect I had. Thank you Fernando!