Pasture plants need to take up 7 kg of sulphur (S) for every 10 kg of phosphorus (P). So, if both nutrients are being applied in reasonably efficient forms, a fertiliser containing 9% P should only need to contain 9×0.7 = 6.3% S. Near the coast, where there is significant input of sulphate in rainwater, the amount of S required is less or even zero.
But most people know that single superphosphate or ‘super’ contains 9% P and a fixed 11% S, almost twice the calculated amount of S required. Furthermore, in higher rainfall areas and low-medium P retention soils, even this amount is insufficient, and super has to be amended with elemental S to make sulphur-super. Why is this? It is simply because much of the sulphate-S gets leached from the soil before it can be used by the pasture (taking valuable cations such as calcium, magnesium and potassium with it). Even though 10-35% of applied soluble P becomes fixed in progressively unavailable forms in our soils, this is still more efficient than is sulphate-S, except in very dry conditions.
It has been known for decades that, except in very dry conditions and on very high P retention soils, finely ground elemental S is far more efficient than sulphate -S. This is why elemental S rather than say gypsum (calcium sulphate) is added to straight super if more S is required, and elemental S is the ‘go-to’ product for adding to the likes of TSP, DAP and MAP.
It is no surprise therefore that by far the most common blend of RPR and elemental S sold by Quinphos was 92% RPR and 8% fine elemental S. With 12.7% P in the RPR, which also contained about 0.8% S as sulphate, this gave a product containing 8.7% S and 11.7% P ; an S:P ratio of – you guessed it – 0.7 to one.
A big proviso is that the elemental S used has to be truly fine – mainly less the 250 microns and all less than 500 mm. This can be irritating to the eyes if not dampened. These days, the cost of prilling molten sulphur with bentonite clay is far less than it used to be. These small water-dispersable hemi-spherical prills contain hundreds if tiny sulphur particles in each prill, which disperse easily in the soil.
The only situations where sulphate is likely to be needed are on extremely low rainfall areas or in cold late winter/early spring if soil S levels are low. Sulphate of ammonia provides a good N boost and takes care of the S requirement in the latter case.
An open letter to New Zealand dairy farmers: December 2018
‘A farmer-lead way to sorting out the environmental circus’
Dr Bert Quin, Managing Director, Quin Environmentals (NZ) Ltd
Updated 29 December 2018
The dairy industry in New Zealand has grown much faster than anyone envisaged, and way faster than our RMA and the Regional Councils were equipped to manage in a way that minimised adverse effects on the environment. The farming of 6 million milking cows and their replacements has unquestionably caused adverse effects on the quality of many streams and rivers, and also some lakes and groundwater aquifers.
Of course, many towns have insufficient water treatment and produce local sources of pollution that must be rectified. Towns that lack the physical and financial resources to do this are likely to be depopulated over time.
But the reality is that NZ has 5 million people and 6 million milking cows. Depending on how you do the comparison, a cow produces 30-100 times as much excreted nutrient and bacteria as an adult human. If you compare daily food intake, the ratio is about 50 to one, so let’s take that. What this ratio means is that NZ would have to have a human population of 50×6 =300 million people for their total effect on water quality and greenhouse gas emissions to equal that of our current cow numbers.
However, as long as our cows are kept out of direct contact with waterways, dung is recycled quite efficiently in the soil; so is dairy effluent if it is managed and stored carefully, and spread evenly as much of the farm as is practicable. A minimum of 50% of the farm should be receiving effluent; on some farms effluent is applied to less the 10% of the farm area, causing excessive nutrient build-up and leaching. Nitrate leaching and greenhouse gas emissions from urine patches and urea fertiliser are a much bigger issue, but effective mitigations such as Spikey and ONEsystem have been developed already, and are simply waiting on the right combination of farmer-awareness, incentives and best-practice requirements for their uptake.
Unquestionably in my view, the biggest existing problem is the eutrophication caused by loss of phosphorus (P) in run-off water and through leaching. The great majority of this loss comes about – sooner or later – from soluble P fertiliser applications such as superphosphate. For dairy farms to be economic at the relatively low food prices demanded by consumers today, compared to those happily paid by previous generations, pasture production has to be pushed to near maximum, which means higher levels of P (and N) are necessary in the soil. When soluble P is used, which is totally unnecessary on established dairy farms, losses of significant and environmentally damaging quantities of P to waterways and aquifers occur.
The here and now
Unfortunately, the organisations charged with maintaining New Zealand’s water quality under the RMA, the 11 Regional Councils and 6 District Councils, are in the main very poorly equipped for the job. Most of their staff do not have the farming knowledge and awareness to recognise a perfect mitigation strategy if they tripped over it. They are staffed predominantly by people who believe that their sole responsibility is to take part in endless discussions and write endless reports that end up either in a long-forgotten computer file or on shelves gathering dust. They simply do not understanding farming, and certainly not the intricacies of managing nutrient cycles and losses. So they increasingly hope that somehow legislating Overseer® will rescue them. In the meantime, they buy time by placing increasingly difficult and expensive on-farm mitigation obligations on farmers. In many cases, these obligations have been thought up by the very research farmers who did the initial research that proved that the fundamental causes of pollution were the use of soluble P fertiliser and inefficient forms of N fertiliser. But now their research funding, chanelled from the taxpayer and farmers themselves through Ballance and Ravensdown, is only available for mitigations that ignore the easiest and most effective change – chanhging the forms of P and N we use, but rather put all the onus on farmers to spend money on poorly effective and very expensive ‘mitigations’ like frequent resowing with chicory and plantain, sediment and P run-off trapping walls and trenches etc etc.
But as has already been demonstrated in court in some areas, the Overseer model was never designed for this use, and is simply not up to the task of being used legislatively. Certainly, it has had a place as a nutrient advisory tool for consultants, but even then it needs to be rebuilt to remove its strong bias towards relying on superphosphate and granular urea. It is too vague on many scientific aspects, and excludes virtually all existing fertiliser-based mitigation strategies that would really help farmers. Instead, it has become a huge part of the problem. It predicts high nutrient losses where these could be greatly mitigated with existing new technologies. It greatly underestimates – by an order of magnitude in many cases – P run-off from, and leaching through, many soils, and underestimates the extent of reductions obtauned with RPR.
Another example is the ‘Spikey’ equipment for detecting and effectively treating urine patches. Despite invites, very few AgResearch or Regional Council staff have bothered to even come and see it. Another is ONEsystem, the system for using prilled urea (instead of granular), which is treated with urease inhibitor solution as it is being spread. Scientifically published trials have shown that it doubles urea efficiency so that only half as much needs to be used. But it is a real mitigation that you can see and touch, so the council staff aren’t interested. Ballance and Ravensdown management aren’t interested either, because it will halve urea sales and profits!
The current situation is a dog’s breakfast, but there is a relatively easy way for farmers to start to take the initiative back. This is to adopt fertilisers and technologies which have the science behind them to prove they mitigate nutrient losses to the environment. Under the RMA legislation, such mitigations must be approved by Regional Councils. Read about the Quinfert RMA 400 range for more details of the mitigating fertiliser option. Once you are using the Quinfert RMA 400 range, demand that your Regional Council set up downstream monitoring of your farm’s water quality.
The best news is, farmers will be saving money in the process, and your production may even go up!
Regional Councils are being given misleading information by the fertiliser industry, along the lines of “RPR is only suitable for small areas of New Zealand”. This is absolute rubbish. At the most, on areas with very low soil P (now very unusual in NZ), very low (-700 mm) rainfall without irrigation, or very low P-retention soils (>90%) with below-optimum soil P levels, it is ideal to include 25-30% of the total P to be applied as quick-release P for the first year or two, to prevent any minor, short-term ‘lag-effect’ in pasture production occuring. The rest – comprising the great majority of farmland in New Zealand – needs only RPR to supply its phosphorus needs.
Dr Bert Quin
Quin Environmentals (NZ) Ltd
Mob. 021 427 572
In most overseas countries, this term is used specifically to refer to a fluid made by mixing high-quality fertiliser ingredients, previously finely ground to below 100 microns (0.1mm), with 40-60% water by weight. Because most ingredients used are quite soluble in water, a saturated solution is formed, with the rest remaining in suspension as fine particles. This is commonly aided by the addition of about 10% of a clay such as bentonite, capable of keeping the fertiliser particles in a suspended state for some hours without stirring.
In New Zealand, the term is, perhaps unfortunately, used more loosely, to the extent of being used to refer to virtually any flowable mix of fine particle fertiliser and or lime in water, most of which require constant stirring to avoid settling out. Such products are applied in a number of ways, including spray booms fitted with very wide nozzles or outlets, from buckets with spinners incorporated in the case of helicopters, or from trucks fitted with specialised on-board grinding, mixing and spreading equipment.
In most countries, this term can be used to refer to any mix of fertiliser and water, including those in which the fertiliser is fully dissolved in water (ie, a true solution) like urea ammonium nitrate (UAN). The term can cover a wide range of particle sizes and concentrations.
The term has not come into common usage in New Zealand. Because of this, and because of the deeply entrenched misuse (relative to overseas usage) of other terms, a prefered definition of fluidised fertilisers is ‘highly concentrated (less than 30% water by weight) liquid fertiliser products containing at least one of the major nutrients N, P, K and S, with or without lime, all with fine-form particle distributions’.
In most countries, this term is typically but not exclusively used to refer to any fertiliser in which all the ingredients are fully dissolved, ie, a true solution. In New Zealand, it has been most commonly used to describe both relatively dilute solutions of fertiliser in water, and such products containing partially-dissolved substances of organic origin, typically from seaweed or fish-processing waste. They are mostly applied, heavily diluted with water because of low ‘recommended’ application rates per hectare, through spray booms fitted with anti-clog nozzles.
This term, not commonly used in many countries, has been used by some commercial entities, particularly helicopter-spreading operations, to describe mixes of finely-ground particles (typically below 100 microns) with water, and/or the application of these via spray booms. The name has been used to infer automatically increased effectiveness, regardless of whether it is present for a particular ingredient. There is typically a claim or at least inference that the total uptake of all nutrients occurs by foliar uptake, i.e. through the leaves, but the actual mechanism by which this occurs is never specified; neither is any hard scientific data provided to support performance claims. Partly because of very high costs of fine-grinding of all ingredients regardless of benefit, ‘FPA’ products tend to be recommended and sold at nutrient application rates that would be considered far to low to maintain production by agronomy and soil fertility experts.
A disadvantage of the ‘FPA’ term itself, besides the confusion over agronomic and cost-effectiveness relative to granular fertiliser for most ingredients, is its confusion with dry or deliberately dampened fine products such as RPR. These fine-particle are often sold deliberately dampened with a few percent moisture, with no other stated purposes other than to control dust and improve spreading accuracy. In fact, it has been scientifically proven that grinding RPR much below 100 microns, which FPA automatically does, confers no additional agronomic benefit because of the well-established common-ion effect between calcium from the RPR and that from the soil.
Most countries use this term almost exclusively to refer to relatively concentrated water-based organic manures, typically applied at high rates per hectare from tanker trucks fitted with special outlets. In New Zealand, the term is used by some to refer to what would be better described as a fluid inorganic fertiliser, especially ones containing a lot of large particles and/or only partially dissolved granules.
All such products are designed with the intention of most if not all of the nutrient content being taken up by the plant directly through the leaves (foliage). To assist in this, the nutrient ingredients are typically present in the form of highly-soluble chelated compounds, with wetting or ‘fixing’ agents added. They are supplied either in ready to use solution form or in powder form for completely dissolving in water. They are typically used on high-value crops only, because of their high cost per unit nutrient. The method by which foliar uptake is achieved or at least promoted is usually indicated to some degree.
Granular fertilisers are made by finely grinding all the components, some of which may then be subjected to reaction with one or more mineral acids, before passing the mix through a granulation drum or over a pan granulator, to produce approximately spherical granules, generally of 4-6mm diameter, before drying and hardening.
Another technique is ‘compaction’, where the finely-ground ingredients are squeezed together under high pressure, typically into a 4-6 mm thick continuous ‘biscuit’, which is then broken into granule-sized ‘chips’. Most potash is sold in this form.
Regardless of whether granule or compaction technology is used, sizing is most commonly 4-6mm, for both ballistic (spreading evenness and width), and agronomic reasons. They are intended to pass through the foliage to the soil surface. On pasture, the rule of thumb is typically that the roots of each plant should have access to at least one granule as it dissolves in the soil. While this may be approximately true for applications of maintenance single superphosphate, it is most certainly not true for granular urea. In a typical dairy pasture, there are typically over 400 plants per m2. However, at a typical granular urea application of 30 kgN/ha (65 kg urea/ha), only 45 granules are applied to each square metre. In cropping situations, both granulated and fluid fertilisers are more commonly placed by specialised machinery close to the rows of plants or seeds, to improve proximity to roots.
A new approach rapidly becoming popular in New Zealand is that of using ‘prilled’ or mini-granule fertilisers, typically in the 0.5-2.5mm diameter range. These provide literally 10 times more particles at the same weight applied as granules, meaning vastly more even coverage. Prilled urea supplied at 30kg N/ha typically supplies 500 prills/m2. Prills also have the further advantage if wetted that many will adhere to plant leaves, allowing some foliar uptake, but without the risk of ‘burning’ and ‘leaf scorch’ commonly induced by liquid and suspension/fluidised fertiliser N applied at more than 10 kgN/ha.
Updated 19 March 2018 by Technical Manager Dr Bert Quin
Global Sustainable Farming Ltd is the supplier of ONEsystem®, a new technology system for optimising fertiliser nutrient efficiency, at little extra cost per kg nutrient applied. This substantially reduces both farm expenditure and nutrient loss to the environment.
ONEsystem® comprises the application of prilled and/or fine-form fertilisers in wetted form. The initial emphasis is on prilled urea treated with urease inhibitor. Other nutrients, efficiency additives such as AlpHa® lime-enhancer, growth promotants such as gibb acid, trace elements, seed and herbicides will all be able to be added as required.
Operationally, the most important aspects of ONEsystem® are –
(1) Changing from using the very inefficient and environmentally damaging granular urea, to applying wetted prilled urea treated with urease inhibitor. This change doubles the efficiency of applied N, meaning only half as much needs to be applied. This automatically greatly reduces N losses to the environment, both in terms of nitrate leaching and greenhouse gas emissions.
(2) Only the most agronomically efficient and environmentally-protective forms of nutrients are used in ONEsystem®. A wide range of additional fertiliser products and trace elements will become available for application through ONEsystem®.
(3) Increased nutrient efficiency also results from the use of the carboxylate polymer AlpHa®, which complexes phyto-toxic water-soluble aluminium (Al3+), which is present in soil micro-sites even in soils with a ‘safe’ pH of >5.5. Al3+ is very toxic to roots of clover and tetraploid ryegrasses in particular. AlpHa® can be easily applied through ONEsystem®. Essentially, it increases the efficiency of lime.
(4) A wide range of additional products, including growth promotants, herbicides and pesticides are being developed for application through ONEsystem®.
(5) Farmers adopting ONEsystem are recommended to apply their maintenance P as reactive phosphate rock (RPR), or blends of it with MAP or DAP where some soluble P is required, to minimise P runoff losses.
ONEsystem has been extensively testing on farms in Taranaki, Canterbury, Otago and Southland in New Zealand, and Gippsland in Victoria, Australia.
First commercial ONEsystem® units operating in Otago/Southland, NZ and Gippsland, Victoria.
Both units are fully committed to farmer clients who kindly made their farms available for testing during the development process. Detailed information was presented to the Massey University FLRC conference at Palmerston North, New Zealand in February 2017. Ongoing on-farm demonstration days will be held for interested farmers and contractors.
Optimising N, P & K has long been in my blood. I was Operations Director of new entrant Quinphos Fertilisers (Aust) Pty Ltd, the first company to import RPR (reactive phosphate rock) into Australia from the late 1980s. This collaboration evolved through to the development and trials of the first wetted prills prototype spreaders in Australia, as a contractor to Quin Environmental Pty Ltd. Several of my clients are already using ONEsystem®.
Over the many years working with Dr Bert Quin, we have created many savings for our clients, while helping to reduce the impact of P and N on the environment in which we all live. We look forward to many more firsts.
In addition to offering ONEsystem® to my clients, and given that I already can provide intra-paddock yield maps of each paddock each week, the next step is to combine the ONEsystem® with VRA (variable rate application) technology. I am currently in the process of creating a ONEsystem® trailed spreader complete with VRA capability.
Q. What is the problem with granular urea as an N fertiliser?
A. While convenient to use, it is seriously inefficient as a source of fertiliser N. Typically only 40% of any one application gets taken up by the plant! Conversions of N to extra dry matter (EDM) are typically in the range of 5-15 kg DM/ kgN applied.
Q. Where does the rest go then?
A. To the environment. Depending on conditions, from 5 to 50% of N applied as granular urea is volatilised as ammonia gas. A lot (up to 50%) gets leached as nitrate-N. Some gets emitted as nitrous oxide greenhouse gas; some as nitrogen gas. You paid for all that!
Q. Haven’t other people tried making urea more efficient?
A. Yes, with varying degrees of success. But they all involve considerable extra costs, such as one or more of the following – expensive extra equipment; processing into fine particle; on-truck or on-site fluidising; higher application costs; coatings; or the use of additives.
Q. What is different about ONEsystem®
A. Dr Bert Quin has called upon his four decades of soil fertility and environmental research and fertiliser industry experience to develop a simple system that literally doubles the efficiency of the normal range of EDM response to granular urea (5-15 kg EDM/kgN), to 10-35 kg EDM/ha. This means that only half as much urea is required in any particular situation. With little cost premium per kg N, savings are very substantial.
Q. How was this possible?
A. By looking carefully at where the losses and inefficiencies were occurring when granular urea is used, and assessing one by one how they could be eliminated, or at least minimised. See the tables for details.
Q. Is foliar uptake of urea always more efficient than urea applied to the ground?
A. No, not always. For example, urea in solution is usually no more efficient than granular urea. It also costs considerably more, and can only be applied at low rates, to avoid leaf scorch.
Q. Are coated urea products always more efficient?
A. No, not always, despite invariably cost a lot more. ‘Fully protective’ coatings can mean the N is released too slowly relative to plant requirements. The efficiency of many slow-release coatings and is very dependent on environmental conditions.
Q. What will be the result if I use ONEsystem®
A. You will need only half as much N to get the same DM response as granular urea, in any situation. The very low cost per kg N premium with ONEsystem mean that you typically save close to 50%. The doubling of plant uptake efficiency means N losses to the environment are massively reduced. Farmers operating under an N-cap regime will be able to produce at least twice as much EDM as they can with the same amount of N applied as granular urea.
ONEsystem®– eliminating N losses and inefficiencies with granular urea
|Granular Urea Loss/inefficiency||ONEsystem® answer|
|Many plants receive no N at all - insufficient number of particles||Use of prills mean 10 times more particles – N supplied to every single plant|
|Little if any foliar uptake, missing out on this very efficient mode of N utilisation by the plant||The use of prills, wetted during spreading, ensures that the product adheres and dissolves on the leaf|
|Very susceptible to ammonia loss||Urease inhibitor minimises this
|Nitrate leaching is a big problem - too much is produced too soon relative to plant N uptake||Faster, more even plant uptake via foliar uptake and better distribution of small particles|
ONEsystem® – eliminating drawbacks with other efficiency alternatives
|Drawbacks of alternative||ONEsystem® answer|
|High cost of product (most coated granular products)||Cost of prills similar to granules; application costs competitive|
|Lack of reliable benefit (granular urea, ‘biologically-treated’ urea)||Wetted prills optimise foliar uptake, nbpt minimises NH3 volatilisation|
|Scorching-excessive instantaneous leaf uptake (liquid or fluidised urea)||Time required for wetted prills to dissolve slows foliar uptake enough|
|Striping due to uneven spread and fines falling behind truck (granular)||Prills give far more even coverage, avoiding striping|
|Difficulty in getting product when Farmer needs it (contractors)||Focused ONEsystem® contractors synchronise with farm rotation|
Click on the file below to see the results of independently-conducted research trials with ONE
(uploaded April 2016)
During his recent travel to Europe, Dr Bert Quin visited research institutes, in Spain and northern Ireland and the Irish Rebublic who are conducting research into various aspects of use of the urease inhibitor nbpt. This inhibitor has a very simple role; it slows down or ‘inhibits’ the conversion of fertiliser N (or urine N when used with Spikey®) for just a few days before decomposing itself into plant-available forms of N and P. The enormous benefit this provides is much, much lower ammonia volatilisation, as the peak concentrations of ammonium in the soil are reduced. Also, the more extended conversion of urea to ammonium automatically means slower conversion to nitrate-N, meaning better uptake of N and therefore better pasture response. The science is a obvious as the results; more than 50% of Ballance clients now use SustaiN (nbpt-coated granular urea), a product Dr Quin developed and introduced through Summit-Quinphos in 2002. Dr Quin said that despite some disappointment over the industry’s initial criticism of the product, it is very satisfying to see that the benefits of the product are now recognised. On average, it improves urea efficiency by 25-30%.
One of the great things about nbpt is the absence of residue problems, because of the rapid decomposition of the product of 10-20 days. Research in Spain has shown that it is completely safe even when sprayed on to vegetables such as lettuce. It has been shown to prevent excess nitrate levels occurring in vegetables. No residues could be detected after 20 days. It is highly likely that it has the same benefit on ryegrass, according to Dr Quin.
The new nbpt-spray treated prilled urea known as ONEsystem® recently developed by Dr Quin with private funding from Global Sustainable Farming Ltd (GSF) takes urea efficiency a lot further ahead again – by 170 to 290% depending on conditions. At this level of efficiency, the great majority of the urea being recovered by the plant, which is the way it should be” he says. Another advantage of ONEsystem® is that, by being designed to be used on a ‘follow-the-cows’ basis on dairy farms, a whole new level of residue protection is built in. “I truly believe that ONEsystem® will revolutionise fertiliser N use in New Zealand” says Dr Quin. SustaiN was a good first step in the right direction, but ONEsystem® is the end-game, he said. Results of independently conducted trials under grazing were presented to the New Zealand Grassland Society conference in November 2015.
Dr Bert Quin, who has brought both SustaiN® and now its far superior son ONEsystem® to the NZ market to reduce farmers’ N costs and reduce impacts on the environment, says Ballance and Ravensdown need to be thinking very hard about the future of granular urea in NZ. Ballance have mentioned recently that they are looking at decommissioning the old Kapuni granular urea plant (which produces just 265,000 tonnes urea per year), and replacing it with a million tpa plant. This step would probably require Ravensdown to commit to purchasing its urea from Ballance; meaning an indirect takeover of Ravensdown, unless the plant was to be owned by an independent entity. The two companies currently use about 800,000 tpa. The excess could be sold at much reduced margin to Australia.
Regardless of the ownership, it will be a massive decision to make. This decision just got a whole lot bigger with the introduction of ONEsystem®. ONEsystem® uses prilled urea, which is made by a different (and slightly cheaper process). “At the very, very least, Ballance should be hedging their bets on this one” says Dr Quin. “They also need to contemplate the fact that ONEsystem® reduces N requirements by over 50% on average, so we won’t be needing a plant anything like 1 million-tonne pa capacity if they get brave and build a prilled urea plant instead”. Dr Quin says Ballance have his phone number if they want to talk.
Without a doubt, 2018 has been the year in which the ability of self-interest groups to bury the truth about deterioration in water quality and gaseous emissions was destroyed, and not before time.
Now at least we can have open and rational discussions about the root causes of these effects, and what can be done to minimise them, without just pinning all the responsibility to achieve this on New Zealand farmers.
As in any industry for that matter, there are a small proportion of farmers who do not take their ethical or environmental responsibilities seriously . As in other industries, the great majority care very much.
The uncaring minority must be heavily penalised for sure.But even more importantly, the caring majority must be given the tools to do the job they want to do. They must be given cost-effective innovative technologies and advice on how to manage nutrient losses, and they must be able to source fertiliser types that are far less susceptible to being lost to waterways than are the traditional superphosphate and granular urea.
This is why I made the decision to get back into the fertiliser importing and distribution business. From my assessment, all the existing independent companies were small, and operate in small areas of the country only. None were in a position to supply true RPR at competitive prices throughout the country. Perhaps most importantly, none have the knowledge and determination to face up to the duopoly over the massive issue of phosphate and N pollution from soluble fertilisers. They are not attacked by the ‘Big 2’ because they pose no threat to them; in fact their mere existence is used as a positive by the ‘Big 2’ to ‘prove’ to the Commerce Commission that there is competition in the fertiliser industry.
Quinfert, the fertiliser division of Quin Environmentals, has brought the first real change to the fertiliser industry since Sumitomo broke their promise to me and sold Summit-Quinphos to Ballance in 2008. Look where that went.But now, Quinfert is once again providing both RPR and blends of it with high-analysis soluble P (QSR) from one end of New Zealand to the other. And the extremely efficient ONEsystem (wetted, urease-inhibitor treated prilled urea) is now increasingly being recognised as being twice as effective as granular urea. Literally only half the quantity of N is needed, simply because the atrocious level of N losses to the environment from traditional granular urea are minimised. These initiatives haven’t made me very popular with the fertiliser industry, but nothing new there!
Many people say to me how crazy they think it is that the ‘Big 2’, who sell over 95% of the fertiliser used in New Zealand, and resist any significant innovation in fertiliser nutrient types, are actually cooperatives owned by the farmers themselves. They say ‘well farmers deserve the hassle they are getting when companies they own are, in the view of many, responsible for 80-90% of the environmental problems’.
While I can understand the frustration, it is a simplistic criticism. Farmers have their own businesses – their farms – to run. They cannot be expected to be fertiliser and environmental experts. No one blamed the private shareholders in VW for the diesel fuel economy scams that were introduced by a small group of engineers and executives with the blessing of top management. These people were incapable of seeing beyond the simplistic bottom line, and displayed a total lack of ethics and the environmental responsibility.
It does disappoint me however that the farmer directors on the boards of the big companies are not demanding a great deal more information and ethical justification from management. If current management simply do not have the ability to face reality and act accordingly, they need to go, now.
The management of Ballance and Ravensdown needs to be taken over by visionaries who can take their staff with them down the triple-bottom-line path, before it is too late and their farmer shareholders are crushed with ever-increasing and expensive on-farm mitigations that in most cases could be avoided simply be changing the forms of N and P we are using.
Personally, I think New Zealand is set for some momentous changes in many areas and industries over the next 2 years, changes that will require great leadership and wisdom. Will that leadership and wisdom express itself? That is the question.
I wish you all a very successful 2019.
Bert F. Quin
Updated 30 December 2018
Quinformation is a series of informal articles written for farmers and farm advisors by Dr Bert Quin, mainly over the period 2009 – 2015. Articles written prior to the rebuild of this groupone website in January 2015 have been updated to incorporate new developments, products, technologies, services and research findings.
Everywhere in the world, before the intervention of man and fertiliser, soil, vegetation and animal systems evolved naturally to make the most efficient use of the rate of nutrients becoming available from parent materials, assisted by the local climatic conditions. Except during extreme events such as flooding or earthquakes, losses of nutrients to the outside environment were exceedingly small. Animals died and the nutrients they contained were returned to the soil during their decay.
Then civilisation came along, and imposed totally new systems, where considerable quantities of nutrients are being removed in produce, and, to maximise production, plant-available forms of nutrients are kept at very high levels in the soil through the use of fertiliser. Unfortunately, at these high levels, nutrients are prone to loss to the atmosphere (in the case of N), and, in the case of all nutrients, in run-off to waterways and in leaching.
Weathering of the soil’s parent material provides some nutrients, but only some. From research at the Winchmore Irrigation Research Station in Mid-Canterbury and elsewhere, it was known that weathering of potassium minerals in the soil provided enough K to maintain even intensive irrigated sheep grazing. However, when land was converted to dairy farming, that equilibrium changed, simply because of the high levels of K going off the farm in milk. So potash (and more trace elements) had to be supplied, although not as much as on the North Island volcanic ash soils.
Dr Bert Quin’s thinking about fertiliser and the maintenance of soil fertility in general was profoundly influenced by his involvement, from 1974 to 1982, with the long-term rates of superphosphate trials at Winchmore commenced by Russell Lobb in 1954, and long-term national comparisons of superphosphate and RPR designed by Dr Quin, and coordinated by him from 1982-87.
The long-term trial at Winchmore showed that long-term, irrigated pasture production without P fertiliser inputs was only 35% of that achievable with inputs of maintenance P, S and lime, whether as SSP or RPR. With fertiliser, soil organic matter (of which 60% is carbon) accumulated over time before reaching a new, far more biologically active plateau, particularly in terms of earthworm numbers, and maintained a high sheep-grazing intensity, without any need for biologically-stimulating amendments and very few trace elements.
A farm that cannot ‘afford’ maintenance fertiliser for more than 3 years is essentially uneconomic…
It is important to note that this was a ryegrass-clover system, with no input of fertiliser N. However, production with this system is self-limiting. As soil organic N fertility rises, grasses become more competitive with clover. As it falls, the opposite occurs. A natural equilibrium in soil organic matter content and biological activity is established.
If fertiliser and lime are with-held, pasture production begins to decline – within 1 to 4 years depending on the initial soil fertility level – by about 5% of the previous year’s production on average. A farm that cannot ‘afford’ maintenance fertiliser for more than 3 years is essentially uneconomic.