Key Learnings from the IrrigationNZ Study Tour to Nebraska

I was part of a 24-person group who went to Nebraska at the start of September 2018.  The tour was organised by IrrigationNZ and was an amazing opportunity to go and see how another part of the world deals with the same issues that we have here.  Below is an overview of my key learnings from the tour.  

Governance of Water

The governance of water in Nebraska is complex. There is Federal legislation, such as the

Endangered Species Act, which the state has to abide by. Alongside this there are also Federal agencies, such as the Bureau of Reclamation that control most of the surface water through storage and diversion infrastructure. The state then sets its own laws around how it will manage its water.

In Nebraska the surface water is manged at state level by the Department of Natural Resources, but groundwater is managed by Natural Resource District’s (NRD) at a local level. For a number of surface water bodies, there are also interstate pacts that determine how much water must remain in the river to reach downstream states.

The NRD’s have a Board that is democratically elected, and are often dominated by rural people including farmers. Despite this, the farmer representatives have been proactive in driving practical change among their peers.  

The NRD system in Nebraska has been very successful in managing groundwater. All takes are controlled through a well permit system that allows for a given number of hectares to be irrigated per well.

Both of the NRD’s that we visited had invested heavily in science to help them better understand their resource. They also look for solutions as both a farm and catchment level, the latter including raising capital to build environmental infrastructure such as that required for augmentation projects.  

Conjunctive Management

‘Conjunctive management’ is a recent development in Nebraska that has largely come about through the management of ground and surface water takes in ‘conjunction’ to achieve interstate pacts. This has involved the NRD’s (the managers of the groundwater) working closely with irrigation districts and the Department of Natural Resources to ensure downstream flows are achieved.

This has included restriction of individual water takes (wells) – controlling any new ones, limiting the irrigated area from existing ones and in some cases placing a seasonal limit on usage. Alongside the implementation of environmental infrastructure such as Managed Aquifer Recharge and Stream Augmentation projects.

Managing Water Quality

Nitrates in groundwater are of significant concern in the heavily irrigated districts of central Nebraska. In some areas over 50% of the land is now under irrigated crop-farming. Historic poor nutrient management (type and timing) and poor irrigation practice resulted in nitrate concentrations being frequently observed over 30ppm – well over the US drinking water standard of 10ppm.

However, in recent years there has been a significant declining trend, with relatively few areas now exceeding 20ppm. This has largely been brought about by a non-regulatory approach.

State law requires the production of water quality and quantity management plans that identify the issues and then require the development of an implementation plan to address them. All the NRD’s have a rule framework, but most of the rules are currently focused on managing water takes and farming practice reporting. Incentives, knowledge and enabling peer to peer learning in combination with environmental infrastructure is currently seen as the way forward for water quality.

The widespread move from surface flood to centre pivot irrigation has been instrumental in reducing nitrate losses to groundwater. This has enabled soils to be irrigated on an ‘as and when’ basis to minimise nitrate leaching. There is now also a push towards the more widespread adoption of fertigation, as it allows ‘as and when’ nutrient applications – significantly reducing the risk of leaching from rainfall events.

Public perception

Despite the widespread use of intensive farming methods, and the water quality and quantity challenges facing Nebraska, the one issue currently not facing farmers at the state level is pressure from the anti-farming lobby or environmental groups.

Of the almost 2 million people living in Nebraska, the majority understand the role of crop farming and ranching in providing for their social-economic well-being. The Nebraskan economy is based on the irrigation of almost 4 million hectares of corn and soy beans and this is widely understood. 

The University of Nebraska research and extension service runs an outreach programme to attract the next generation to agriculture. This currently interacts with one in every three school age children in the state, providing an agriculture ‘101’ and highlighting the exciting career opportunities that exist within it.

Keri Johnston, Irricon

Natural Resources Engineer

In the words of Rachel Hunter - it won't happen overnight, but it will happen...

Wasn’t the whole election one big roller coaster?  If we have learnt one this from this whole affair, it is that we are all very passionate about our water resources – not necessarily for the same reasons, but passionate none the less.

Regardless of who ends up running the country (at the time of penning this blog, Winnie was still  courting both the National and Labour parties), I think it is clear that public opinion will ensure that water management and associated policies will be addressed is some way, shape or form by the incoming government.  Given this, I think it is important (and timely) to look back and acknowledge where we have got too in relation to this, but also to look forward at where we can still go.  

The National Policy Statement for Freshwater Management (NPSFM) and Regional Plans

Most regional councils now either have notified or operative plans which outline their methods for addressing water quantity and water quality.  While no two plans are alike, the NPSFM requires limits are set, therefore, all plans do just that – they set allocation limits for surface and groundwater resources, as well as water quality limits.  It is the latter which takes various forms including property limits and/or catchment limits using Overseer, in stream water quality limits, and the development of the Good Management Practice (GMP) framework.    Many councils have also adopted the use of audited Farm Environment Plans to be able to monitor, measure, report and ensure that farms are meeting their environmental obligations. 

As with anything in life, good things take time.  Councils are in the process of rolling out and implementing these plans now.  The effects will not be immediate, but they need to be given a chance to actually work. 

It must also be remembered that for many areas, it is as much about maintaining the already good water quality that exists – this is not allowed to deteriorate.  For those few areas where improvement is needed, the plans bite much harder, and that it totally appropriate.

The fact that all of this has occurred seems to have been completely overlooked by many, and it’s not just politicians I’m referring too. 

How are we meeting our environmental obligations already?

Figures provided by Irrigation New Zealand show that since 2011:

·       

• $10 million invested in audited Farm Environment Plans;   
• $600 million invested by existing irrigators upgrading to modern, efficient irrigation systems;
• $18 million invested in precision irrigation technologies;
• $15 million invested in installing irrigation decision-making technologies;
• More than 24,000 kilometres of our waterways have already been fenced off to exclude stock at a cost of $220 million. 

As we continue to meet our environmental obligations, you can only expect these numbers to increase.  It is noted that this expenditure is all on farm, reinforcing the point that water quality will be addressed at the farm level. 

Looking Forward

Regional Councils need to continue to implement their plans. This may seem like an obvious thing to state, but it’s true nonetheless.  Consistent messages and enforcement from the regulatory bodies will be a must.

I believe that many farmers are on board with GMP (the on-farm practices) despite still being largely ignorant or merely confused by the new environmental regulations.  Education is still key to the success of this stuff, and that has to come from all involved – banks, valuers, real estate agents, farm advisors, customers… anybody involved with the farm.  And, many farmers are being innovative and taking up technology where it is available.  You only have to look at the statistics above regarding the investment to date in irrigation upgrades and precision irrigation technologies.  

And last, but not least, time, time, time.  To quote Rachel Hunter from her Pantene ad, “it doesn’t happen overnight, but it will happen”, and it is happening.  Get on board, and keep it up.

 By Keri Johnston, Irricon Resource Solutions

Phone 0272202425 or email keri@irricon.co.nz

Stock Exclusion - What's the go?

Out and about recently, Lilian Sherman, our North Island Rural Environmental Specialist, has heard a lot of discussion about the stock exclusion rules coming into play.  Unfortunately, a lot of what she has heard has had a serious dose of the ‘chinese whispers’ and the end result is that there are a lot of myths out there with regards to stock exclusion.  Below, Lilian dispels some of those myths and provides you with some confidence around the rules.

While there is no formal definition, stock exclusion generally means to exclude stock by some means from entering a waterbody.  In most cases, the stock exclusion definition does not include sheep or goats, as sheep and goats do not tend to linger in water!  In most cases the means of achieving stock exclusion is not specified, therefore the best method or technology for each situation can be used.  This may be a permanent fence, a hot wire, or as is currently being developed, virtual fencing.
Why is stock exclusion necessary? Stock entering waterways can cause significant damage by contributing nutrients (primarily nitrogen and phosphorus), sediment and faecal coliforms to our waterways. They do this though the direct deposition of dung and urine into rivers, treading damage and reduction in beneficial vegetation that results from grazing stream banks.

As part of the Clean Water package recently released by the Ministry for the Environment, there are proposed National Rules for Stock Exclusion.  Consultation on the proposed stock exclusion regulations and other aspects of the Clean Water package closed on 28 April 2017. This feedback is being considered and will inform the final decision on the National Rules.  The proposed stock exclusion rules are practical and there are different requirements for different classes of stock and for topography (plains, rolling and steep).  More details are available on the Ministry for the Environment Website (https://www.mfe.govt.nz/sites/default/files/media/Fresh%20water/next-steps-for-freshwater.pdf).

The proposed National Rules for Stock Exclusion recognise that for some landowners, there may be significant practical constraints that mean they are unable to meet the new requirements. In those cases, landowners can apply for permission to instead develop a stock exclusion plan with their regional council. The plan may include alternatives to fencing or mitigations to reduce the impact of stock access to waterways.  An example of this would be providing alternative areas of shade and reticulated stock drinking water, which may also provide other economic and animal health benefits.

It is important to note that the National Rules for Stock Exclusion will form the minimum requirements, and councils may choose to regulate over and above these in their regional plans.

There are some challenges excluding stock from waterways, including the effects of flooding, the proliferation of weeds and pests and access through vegetation to waterbodies.  These are valid issues and I have confidence that farmers will find practical solutions for these as the rules come into play.

In the meantime, if you are putting in new fence line or carrying out fencing maintenance, consider whether there is an opportunity to make a change to a fence line to exclude stock or make it easier to exclude stock in the future, but its also an important consideration for any development on farm such as irrigation (whether new or upgrading) and the location of waterways should be a key consideration in any design being undertaken. 

Keep an eye out for the final versions of the National Stock Exclusion Rules.

Lilian Sherman, Irricon Resource Solutions Limited.
Phone: (021) 378 308
E-mail: lilian@irricon.co.nz

Lilian is a Rural Environmental Specialist and Director at Irricon Resource Solutions, who works with farmers and horticulturists to prepare farm environment plans, resource consent applications and to assist with nutrient management and Overseer modelling. 

Lilian grew up on and lives on a sheep and beef farm, she has a practical knowledge of farming, including sheep, beef, deer, dairy, cropping and horticulture and combines her passion for farming with a wealth of nutrient management and environmental expertise in this role.

'Tips, Tools & Technology for Efficient Farming' - Workshop Series

Do you want to improve the nutrient and irrigation management on your farm but are not sure where to start? Come along to a free 'Tips, Tools & Technology for Efficient Farming' workshop jointly hosted by Lindsay NZ, Agri Optics New Zealand Ltd and Irricon Resource Solutions.

Over the course of the workshop we'll cover off a range of topics from nutrient management, irrigation management and hardware, precision agriculture and how these all tie in with farm environment plans for efficient farming.

Please use this link to register - Register me for a workshop please!

We look forward to seeing you there

The Finance of Farm Environmental Improvement

There has long been the perception that good environmental management comes to the detriment of the overall farming business.  I’d like to think we’ve got beyond that, but with nutrient regulations coming into play, I suspect that this perception if running rife again!  But, it doesn’t have to be that way, and in fact, it can be positive financially for the farm.  In this post I’m going to show you examples of where environmental and financial gains can be made for farms, and that the two objectives don’t have to be at logger heads.

Resource consents held by a farm is the obvious place to start.  Quite often, consents were obtained, shoved in a draw and never looked at again.  But consents are a valuable asset to a farm, and having the right consents is critical.  The three questions that need to be asked is:

1. Are they correct?  For example, is my rate of take correct, is my effluent discharge area actually right, are my cow numbers to be milked right?
2. Could they be better?  For example, does my effluent consent cover my whole farm to give me flexibility?  
3. Are they even needed?   With Canterbury having changed its plan twice in the last 10 years, there are now consents that were needed under the old plan that are not needed under the new plan, for example consents to store dairy effluent.  

As an example, a consent audit was undertaken on a farm which had six consents to take and use water, and a dairy effluent consent.  This means:

• Seven lots of monitoring charges.
• Old take consents that no longer reflected what was happening on farm, including that none of the consents specified whole of farm for irrigation or effluent, and had horrible 14 day volumes that didn’t fit with newly installed pivot irrigation.  

The six take consents were merged into one consent, 14 day volumes removed and replaced with one annual volume for the farm, and the whole farm was also be irrigated with any source.  This means:

• Better use of the water – the farm was no longer restricted by horrible 14 day volumes, so is able to irrigate when needed.
• Easier to comply with – One consent versus six…..
• Flexibility – The water can be used anywhere it’s needed, rather than from a certain point on a certain area.  

The paperwork is now sorted, so next it’s time to look on farm.

Is your infrastructure up to scratch?  This can encompass all types of things, but common examples include having effluent storage that’s big enough, or your control box says that the pivot is putting on 10mm, but how do you know that’s what actually coming out the sprinklers?  Right the way through to the question “is your pump and mainline adequate and not costing you more to run than they need to be?”  Has it been looked after?  Things like sprinklers broken or not turning, or missing altogether!  Remember that an irrigator has moving parts – how often are these checked and serviced?
And finally, how do you make the decision to start irrigating or when to discharge effluent?  The neighbor is not generally the most reliable tool to use, and if it’s too early, then its water wasted, effluent and therefore nutrient wasted, and production lost.

Now let’s take a look at lost production due to infrastructure.  We’ve got a farm with an intake that required frequent rehabilitation, and cleaning and clearing of weed despite it having a screen which resulted in reductions in flow.  It also had a mainline configuration resulting in substantial system losses, and pumps not performing at their optimum efficiency.  The farm needed 4.5 mm per hectare per day for optimal growth.  Because of the intake and mainline issues, it was constantly only getting 2.5 mm per hectare per day.  This resulted in a shortfall for the farm of 2650 cubic metres per hectare.  The impact on production from this shortfall is 10% or 1.5 tonnes of dry matter per hectare of average annual growth loss.  If this additional growth is worth 28 cents per kg of dry matter, this this is $420 per hectare.  And all this because the infrastructure was not doing what is supposed to be doing!

Now let’s compare a farm with soil moisture monitoring to one without it, both located within 1km of each other, of similar area, lay of the land, and irrigation systems.  For the 2013/14 irrigation season, the farm with soil moisture monitoring used 3213 cubic metres per hectare.  The farm without soil moisture monitoring used 5389 cubic metres per hectare.

• Energy Cost to farm with soil moisture monitoring = $321.30 per hectare
• Energy Cost to farm without soil moisture monitoring = $538.90 per hectare

And let’s not forget that less water applied = less nutrient loss.

So why look at all of this stuff I hear you ask?  The reality is that the use of resources on farm cost money:  Water, energy, fertiliser and/or effluent…. Increased production tends to not only cost money, but it is also considered to have environmental impacts.    In my view, it is really important that farmers don’t view the two as being incompatible.  A Farm Environment Plan and the process involved in preparing one, is a place to assess the risk of your farming business to the environment.  But you should take it as an opportunity to look at your business as a whole, and use it as a way to not only achieve good environmental management, but good “full stop”.    Don’t view the process as a hindrance, and just another regulation box to tick. Take the positive approach.

So, my final comments!

This has been a snapshot of the opportunities that exist on farm where being environmentally responsible can also be financially beneficial. So, use what’s coming from a regulation point of view to take a look at your whole business.  You might be just pleasantly surprised at what you find, and be able to make positive changes to your business all round.

Keri Johnston, Irricon Resource Solutions Limited.
Phone: (027) 2202425
E-mail: keri@irricon.co.nz

Keri’s expertise is in the field of natural resources engineering and resource management, primarily in water resources, irrigation and nutrient management. As well as doing this, she farms with her husband and two girls at Geraldine.  

Farm Environment Plans

There are a lot of buzz words floating around at the moment – nutrient management, nitrogen baseline, change in land use, Overseer, nutrient budget, and the topic of this article – farm environmental plans.

So what is a Farm Environmental Plan, or FEP as we like to call it?  It is a tool that guides farmers through an assessment of a farms environmental risks or issues, and is a written plan outlining how those risks or issues will be managed.  Because no two farms are alike, no two FEP’s will be alike either.  Each farm is unique in terms of its landscape, natural resources, farming practises and goals.

FEP’s are being used as a means for farmers to meet water quality objectives and outcomes, or limits set in regional plans.  In Canterbury for example, nearly every farm will be required to have and implement a FEP by 2017.  

The process in preparing a FEP is the same for all farms, and is really simple.  There are five easy steps.

1. Assessment

What and where are the environmental risks or issues on farm?  The farm specific environmental issues or risks include poorly drained soil, streams, waterways, wetlands, springs, steep or rolling topography, but this also refers to practices being carried out on farm.  Do you store fertiliser on farm?  How is it stored?  How is fertiliser spread and when?  Is the farm irrigated, and if so, how do you determine when to irrigate?  Cultivation practices, location of silage pits…

The second part of this is to consider what has already been accomplished.  Have you already fenced off waterways, carried out riparian planting, swapped to a GPS certified fertiliser spreader, installed soil moisture monitoring probes to determine when to irrigate, only make or purchase balage rather than pit silage?

The third part is the Overseer component. What are the losses that are occurring from your farm now?  How do they compare with any proposed catchment limits being talked about?  If your losses are high, then what changes can you make to reduce these?

2. Response

Now that you have identified the environmental issues or risks, and worked out what you have already accomplished, it’s time to fill the gaps. What else can be done?

3. Plan

What, how, where, when and how much?  Fencing off waterways for example – your assessment may have shown that there is 10km of fencing that needs to be completed.  There may be financial constraints that mean that all 10km cannot be fenced off in one go, but plan to do 2.5km per year for the next four years, and identify the areas that will be done each year – there may be a section that really needs to be done sooner rather than later as the environmental risk is higher (for example, a section where stock access several times a year as opposed to once a year), and this gets done in year one.

Any plan has to be reasonable and achievable – no point in making a plan that will never be able to be carried out – that defeats the whole purpose!

4. Implement

Carry out your plan.  Monitor what you do and record progress.  This is really important as FEP’s are subject to annual audits by independent people, therefore, you want to be able to show any auditor exactly what you have done, and whether it has achieved the environmental outcome you expected it too.

5. Review

Review your progress annually.  This can be part of the annual audit.  Reviewing your progress is important.  Have you noticed that some of your responses have worked really well, but others seem to be of very little environmental benefit at all?  A FEP is a living document, and as you learn what works and what doesn’t, then your FEP needs to be updated accordingly.

The most important thing to remember is that a FEP is for you and your farm, and it should be written this way.   It should not be an onerous task, nor viewed as a way to “trip you up”.    Use the opportunity to have a good look at the way you do things on farm, and why you do what you do. There are many other benefits too – not just environmental.  There are also financial gains to be made as things like water efficiency increase (less pumping costs), nutrient and fertiliser management practices change (less applied = less purchased).

There are many resources available to assist with preparing a FEP including toolkits and templates. But sometimes, you just need someone to point you in the right direction, and this is where we (Irricon) can help.    We are farmers too, and are going through the same process.  We are also learning as we go – I cannot stress enough that a FEP is not stuck in time – once it’s prepared, that’s it, end of story, but it is a living document, and as we learn, we are passing that knowledge on, as are many others. Therefore, don’t hesitate to seek advice and support from those in the know.

By Keri Johnston - Irricon Resource Solutions Limited.

Keri’s expertise is in the field of natural resources engineering and resource management, primarily in water resources, irrigation and nutrient management. As well as doing this, she farms with her husband and two girls at Geraldine.

Phone: (027) 2202425
E-mail: keri@irricon.co.nz

Lincoln University Dairy Farm Open Day 2016

This Saturday the Lincoln University Dairy Farm (LUDF) will open its gates to showcase the operations of a commercial dairy farm.

Visitors will get an opportunity to ‘get up close’ and learn about the transformation of ‘sunshine into food’. 

Included in the program is the importance of water to enable a dairy farm to produce milk that we get to enjoy on our Weetbix every morning.

The farm will be open to the public from 1pm-4pm. This is a great opportunity for anyone in the Christchurch and Canterbury region who has not had the opportunity to visit a dairy farm before.

For more details visit www.farm-openday.co.nz.

Improving Irrigation Efficiency for Only $50

Dr Anthony Davoren is renowned as one of New Zealand’s leading irrigation consultants, establishing Hydroservices in 1983. If you have a question about irrigation management, soil and soil water assessment or surface and groundwater water resources then Tony will have the answer. What sets Tony apart is his practical, hands-on approach and the way he communicates information in a way that farmers can easily understand and relate to… I mean how many other speakers will you find presenting from a hole in the ground!

The Waihao Wainono Group and Morven Glenavy Irrigation recently hosted a field day focusing on improving irrigation efficiency. H2Grow is lucky enough to be able to share with you some short videos from this day. In the first in this series Tony explains how the root depth of the pasture or crop you are growing should be considered when deciding on the most appropriate soil moisture measuring equipment for your property.

Considering Root Depth when Measuring your Soil Moisture Levels

Keep a look out for the next video in this series where Tony explains how to measure drainage so that you can better manage your irrigation and prevent irrigation water, and nutrients, draining through the soil... and his top tips of how to greatly improve your systems irrigation efficiency for as little as $50!

Thank you to Dr Anthony Davoren, Waihao Wainono Group and Morven Glenavy Irrigation.

Soil Properties Critical when Applying Effluent

Dairy effluent is a great source of nutrients for growing pasture. But if not managed properly effluent can also be a significant source of contaminants which harm our waterways. Understanding how soil properties affect nutrient loss is a key to maximising the benefits of effluent on farm and minimising its impacts on waterways.

Soil texture and structure determine the amount of water that can enter and be retained within a particular soil, and the rate of transmission of excess water through that soil. So effluent irrigation systems should be matched to soil properties to minimise runoff and leaching. The rate at which effluent can be applied to the land for maximum production benefit is determined by the soil’s properties including structure, porosity and infiltration rate.

The nature of the effluent and cattle treading on soils can affect the infiltration rate. Treading damage, which occurs most when the soils are wet, significantly reduces the infiltration rate. For some soils this can result in accumulation of effluent below slopes and in hollows. It can then enter surface waterways.

Movement of water through soil pores is generally described as hydraulic conductivity. When hydraulic conductivity of the soil is low, irrigation of effluent will result in ponding and run-off once the total water capacity of the soil is exceeded or if application rate exceeds infiltration rate.

Low rates of hydraulic conductivity are found in soils that are poorly drained, and ponding and runoff often occur with high rainfall. Many of these soils are artificially drained to reduce the incidence of ponding and water-logging, and this carries a risk that effluent can bypass the soil and be directed rapidly into waterways

Leaching occurs as excess water moves through the soil. So soils with lower water holding capacity are more susceptible to leaching, while soils with high water holding capacity (deep silt loams) can store significant quantities of effluent.

The soils that have low available water holding capacities, are the shallow to moderately deep soils, as well as sandy or stony soils. Effluent irrigation on these soils is likely to result in leaching unless it is applied at low rates and in small doses. The irrigation system on these soils must be capable of low rates of application to gain the maximum nutrient benefit.

Drainage and the level of biological activity of the soil at the application site are important. Aim to apply effluent at a rate that keeps it in the root zone so that the nutrients can be utilised by pasture.

Permeable soils with a deep water table and no drainage limits are best for putting effluent on. However, on stony soils the risk of effluent draining directly to ground water would be an issue to consider. In such situations, application depths and rates should be adjusted to account for this risk.

Another issue is "bypass flow". When effluent application rates are higher than infiltration rates, water can enter continuous macro-pores that are open at the soil surface, and then move very rapidly via so-called "bypass flow" through a relatively dry soil matrix. This means little opportunity for the water to be retained within the root zone and high leaching of nitrate is likely to occur. Bypass flow of farm dairy effluent can occur in soils that undergo shrinkage and fissuring during drying, especially when these soils have been previously compacted by treading.

Efficient effluent storage provides flexibility when it comes to application and helps maximise nutrient uptake (image: DairyNZ)

A key to avoiding over application can be having adequate effluent storage so that irrigation can be deferred if conditions aren’t right. DairyNZ has released a new smart-phone app to help farmers apply effluent more efficiently. The Dairy Effluent Spreading Calculator app provides dairy farmers and effluent spreading contractors with guidance around nutrient application rates based on the depth and type of effluent they apply.

H2Grow would like to thank Bala Tikkisetty for this blog post. Bala is a sustainable agriculture advisor at the Waikato Regional Council.

If  you are keen for further information about best practice for applying effluent you will find a raft of useful information on the Waikato Regional Council website.

Or alternatively contact Bala directly, email bala.tikkisetty@waikatoregion.govt.nz or call (freephone) 0800 800 401.

Reduce the Cost of Nutrient Loss with Precision Ag (Part 3)

In the last two blogs we looked at how Precision Ag can help with managing the nutrient and moisture levels in the soil profile. This blog looks at how an EM survey can assist in relation to the physical characteristics of the land for your farm environment plan.

As an EM survey is conducted, the readings are logged by 2 cm horizontally accurate RTK GPS. This allows us to not only build a great picture of your soil profile but also the surface of the area surveyed as well. This in its own right can be a very powerful tool for overall land management and also the farm environment plan. As the flow of water can cause the movement of soil and nutrients.

With this layer of data we can make 3D contour or water flow maps. So you can see where water will move in a rain or irrigation event and where potential areas of soil/nutrient issues may occur, so buffer zones may be necessary to mitigate this potential problem.

 

Picture 1: 3D elevation map showing the potential water flow across the area.

Our software platform, VA Gateway, can model the flow of water and we make an animated model of how the surface water will react over time. On the first image (picture 2) below you can see the surface water after a rain event then moving down the images how the water moves from the higher area and ponds in others. This sort of information is of great use to the client for highlighting potential issue zones.

Picture 2: Simulator showing the water flow after a large rain event.

Picture 3: The water is flowing from the higher areas.

Picture 4: The water is ponding in the low lying areas.

With variable rate irrigation application maps on ‘hilly’ land we can combine the EM and slope maps, to take into consideration the severity of slope over the EM. That is to say it may be a soil type that requires a higher water rate but when you take into consideration the degree of slope, then higher application rates would be moving down the slope as well infiltrating the soil profile, so therefore a lower application rate is needed on the steeper sloped areas to reduce the chance of runoff. By managing the potential flow of water across your property you are also managing the movement of soil and nutrients.

 

Picture 5: At the top left the EM zone map, on the bottom left the slope map. On the right the two maps have been combined to form an application map using both characteristics.

In Picture 5, on the right side is the application map where is red low EM, green Medium EM and blue high EM - the matt colours indicate low slope, the bright colours higher slope.

So with the use of Precision Ag you can gather very comprehensive maps showing the levels variability in nutrient levels, in soil characteristics and in topography for your property. By measuring these variables you can then monitor them and manage them, which are prime requisites for your farm environment plan.

Chris Smith

Agri Optics NZ Ltd

Reduce the Cost of Nutrient Loss with Precision Ag (Part 1 of 3)

Precision Ag can help you in many ways with your Farm Environment Plan (FEP). Precision nutrient management, EM maps, topography data,variable rate irrigation (VRI) and moisture probes are all tools available to help you manage your FEP and mitigate any potential issues you may face - Reducing costs to your farming operation and the environment.

I will be looking at how each of these can help you over the next few blog posts (to make sure you don't miss out pop your email address in the "Follow By Email" box, to the right). In this first blog of three I am looking into precision nutrient management.

Improving Nutrient Management with Precision Ag

The objective here is to maximise nutrient use efficiency while minimising nutrient losses into water. This can be accomplished by looking at the nutrient levels in the soils themselves as well as monitoring the moisture in the soil profile to ensure you don’t leach nutrients out with over watering. Precision Ag can help you in several ways to achieve this, this week I will look at the nutrient levels themselves.

This is done through either grid or zonal soil sampling. Instead of taking one soil sample per field or block, you sample in a grid at a resolution of one site per hectare or take samples within each known soil zone from your EM survey. Whichever way the samples are collected the sites are geo-referenced that means you can go back to the same point every time you sample so you can see how you are managing your nutrient levels over a number of years. At each site 12-15 cores are taken and placed in a bag, labelled and sent off to the laboratory for that sampling point.

Picture 1: Geo referenced sampling points in a field.

When you receive the laboratory results, they look similar to those you normally get however the critical difference is they are all geo-referenced and are at a higher resolution i.e. one per hectare. The data received can then be processed to create a nutrient zone map; with nutrient levels grouped in ranges for the given area and given nutrient.  From that layer of data application maps are made to match the soil and crop requirements.  The main nutrients commonly applied using this variable rate method are potash, phosphate and magnesium as well as lime for pH.

Picture 2: A map showing the varying Olsen P values across a field.

By only applying what is needed where it is needed means you minimise any over-application of product with financial and environmental implications, and you also maximise the crops potential on a nutrient level. By using this method you can mine nutrient-rich zones reducing nutrient levels in those areas and apply only what is required elsewhere.

Chris Smith

Agri Optics NZ Ltd

International Recognition for Precision Ag Advocate

Here on the H2Grow blog we showcase leading edge precision agriculture technologies and practices often through case studies of growers achieving success through there application. But in today’s post we would like to showcase a true leader in precision agriculture – Craige Mackenzie. Craige is a leading advocate and role model within New Zealand, a pioneer in the adoption of precision farming techniques.

Craige has recently been awarded the 2016 PrecisionAg® Farmer of the Year. This is a huge accolade and NZ should be very proud that the award has gone to one of our own!

The PrecisionAg® Institute recognises outstanding people, programs, and organisations that are making a difference in the precision ag industry. Each year’s winners have devoted their careers to the technology that improves crop production stewardship, agronomy, and efficiency.

Craige and Roz Mackenzie at Greenvale Pastures

Craige’s focus has been on utilising precision agriculture systems to maximise nutrient and irrigation efficiency for improved farm sustainability, both environmental and financial.

Craige and wife Roz farm Greenvale Pastures, a 200ha fully irrigated cropping operation near Methven specialising in vegetable and small seed production. They are also 50:50 equity owners in Three Springs Dairies, a high-output dairy farm with 1,200 milking cows. Their adoption of precision ag technologies has resulted in improved seed quality and yield with reduced inputs.

The utilisation of Growsmart Precision VRI has led to annual water savings of 32% and resulted in vastly improved water management on their variable soils. Resulting in three years of no measured nitrate losses to the groundwater!

In this recent video Craige and Roz share some of their secrets to farming sustainably and profitably through by employing precision ag.

In 2010 Craige and daughter Jemma established Agri Optics Ltd., New Zealand’s first precision agriculture service company providing precision ag tools and services to NZ farming systems with a focus on field sensing (crop sensing and Electro Magnetic soil surveying) and spatial data management solutions. Agri Optics NZ is now recognised as New Zealand’s leading precision agriculture company. And are also coincidentally partners in the H2Grow crusade.

This post has been put together by Sarah Elliot (Lindsay NZ), and I would personally like to congratulate Craige for being recognised with this prestigious award - Congratulations!!

Managing Environmental Compliance with Precision VRI and EM Mapping

Farm Fast facts:

Farm Name: Seadown Dairies

Cows Milked: 620

Length of VRI Pivot: 565m

Production: 1705/ha, 278000 KgMS

Pasture Grown/Harvested: 17,000 KgDM /14,500 KgDM

Key Benefits from VRI system: Reduced track maintenance, reduced pugging damage less water wasted.

Sustainable farm management was a major driver behind Brendan Caird’s decision to install Lindsay Growsmart Precision VRI with FieldNET on his 565m pivot. A major feature of the farm is a spring fed stream that flows through the middle of the irrigated area of the property. Totalling an area of approximately 5 ha, the streams and springs add to the visual appearance of the property and have been fenced and planted into a riparian zone. However without VRI effective irrigation management would have been considerably more difficult. By installing the VRI system Brendan is now able to work around mother nature and reduce his farms overall impact on the environment.

Riparian Zone in the middle of the VRI Pivot

The costs of irrigating his races and tracks were also a big part of the equation.

“Stock flows better, track maintenance is reduced and water is not wasted on unproductive areas” says Brendan who uses VRI to improve the conditions on the farm races. Nearly 5Ha of the 93Ha irrigated area is able to be avoided which includes races and waterways which allows Brendan to utilise that saved water elsewhere.

With an allocation of only 3.2mm/ha/Day irrigation practices need to be as efficient as possible at Seadown Dairies to maximise water use for grass production. Brendan also finds benefit in the VRI system to help remove paddocks from the irrigation round that are set to be re-sown. In the case of the 2016 season Caird planted fodder beet and set an irrigation plan to avoid the paddock whilst it was being cultivated. You can see the effects of this below. The yellow is the paddock that was avoided. The pink is for zones that were a part of the avoid zones.

As Applied Irrigation for the season. Note the paddock in Yellow.

Agri Optics conducted an EM survey on the property and the major soil zones were able to be identified see (http://www.agrioptics.co.nz/portfolio/em-survey/ for more info). The next step that Brendan and his team are working on is to begin irrigating to the EM soil zone plan. With multiple soil management zones identified on the property the goal is to water according to the relative requirements of each soil zone. This is aided by soil moisture sensing equipment to give the exact time that irrigation is required. Further to this Brendan can also be sure that soils are not being overwatered and water is not being wasted which Brendan says helps make his farm environment plan more comprehensive.

Blog this week by Nick @ Agri Optics
Find us on Facebook or follow me on Twitter.