Celebrating 10 years of Irrigation Innovation

It’s a classic story of Kiwi innovation.

One summer’s evening in 2004, two Massey University engineering graduates, Stu Bradbury and George Ricketts were working a summer job assembling irrigators on the South Wairarapa farm of Brian and Jo Bosch. 

Over a cuppa, Stu, George and Brian discussed the challenges on the Bosch’s farm caused by the limitations of the existing pivot irrigation system.

“Where the pivot went over the races was wet and mucky,” says Brian.  “We were also getting a number of lame cows, who got wet feet and bruising on the muddy race.”

Brian Bosch on his Wairarapa dairy farm

Blanket irrigation was the problem. They needed a way of irrigating specific areas that needed it but keeping vulnerable parts such as the race dry.

Back then nothing on the market could manage the water flow in targeted and controlled quantities, to specific parts of the farm depending on topography and soil type.

“We saw wet areas where crops weren’t growing, and dry areas without much water. So there was an obvious need for a system to specify where you needed water and how much,” says Stu.

Before long George had the solution and in 2006 they began developing the prototype that would become Precision VRI. VRI stands for variable rate irrigation, ensuring precise amounts of water or nutrients are delivered over multiple crops, soil types and terrains.

To make best use of the technology on paddocks with variable soil types and terrain electromagnetic (EM) soil mapping is recommended. EM mapping measures soil conductivity which is an indicator of soil texture (along with other characteristics) and therefore soil water holding capacity. The Precision VRI system can be easily programmed using the FieldNET app to customise irrigation according to the EM map.

The system can be used to ensure that only the areas that need water, get water, and at the right levels.

Over the past decade Precision VRI has enabled New Zealand’s farmers, food producers and agricultural contractors to achieve better results, driving efficiencies and saving money – to the benefit of agribusiness, not only for dairying, but in sheep, beef, horticulture and arable farming.

In 2011 global agribusiness leader Lindsay Corporation acquired the NZ company WMC Technology Ltd under which the Precision VRI technology was developed. Through doing so the not only gained the rights to market the award-winning technology but also provided significant backing for George, Stu and the team to continue developing irrigation solutions.

From the archives: George and Stu at a farm mapping job in 2010 (above). Stu, George and Paul (below) receiving the Supreme Award at the Manawatu Business Awards 2010, WMC Technology Ltd also won the Innovation Award and the Workplace Health and Safety Award.

“We are working on new iterations of the software,” says Stu.

“Now, everything needs to be mobile-friendly so that is where our efforts are focused.”

Future plans to market the system internationally will give farmers world-wide the advantages experienced by New Zealand farmers using the system.

To find out more about the Growsmart Precision VRI system call 0800 438 627 or visit www.lindsaynz.com.

Irrigation Evaluations (aka Bucket Testing) - Including tips for testing VRI systems

Spring is here but we are seeing all four seasons rolled into one some weeks which is not an anomaly. The soil moisture levels in our region have had a healthy boost in the last few days but if the media reports are true we may be in for a dry summer - please don't shoot the messenger, I'm only relaying what I have heard.

Should this transpire then that is even more reason to ensure that our irrigation systems are applying water as efficiently as possible so that we are maximising the amount of water applied that is available for plants to grow. An irrigation evaluation is a way to assess the efficiency and distribution uniformity of your irrigation system to ensure it is performing as expected.

An irrigation evaluation will help identify causes of any poor performance and (sometimes with the assistance of a qualified professional) show how these can be resolved. Increasing irrigation effectiveness and efficiency will allow you to grow more for less.

An irrigation evaluation (often referred to as a bucket test) is simple enough to carry out yourself, there are several good guides freely available to walk you through this process. For more information check out:

IrrigationNZ - Bucket Testing Resources
DairyNZ - Irrigation Evaluation Guide

The guides recommended above will walk you through how to carry out a standard bucket test however before you begin you need to consider any additional technologies that enhance your irrigation system. For instance if your system has variable rate irrigation (VRI) technology then you will need to take this into account when planning your bucket test. Lindsay NZ, the developers of the Growsmart Precision VRI system, have created a step-by-step guide that explain these additional considerations in more detail.

Growsmart Precision VRI - Bucket Testing Tip Card

If you are not in favour of the DIY irrigation evaluation option then consider contacting an accredited evaluator, this would also be recommended if your own test identifies potential issues that warrant further investigation. If you have additional technology such as a VRI system then ensure that whoever is carrying out the test is aware of this and that they carry out the recommended additional steps. If you need further help then contact your irrigation dealer, many dealers also have accredited evaluators on hand.

Irrigation system checks and maintenance should be undertaken at scheduled times over the irrigation season (the more hours your irrigator runs for the more regularly these checks should be carried out). Recommended irrigation system maintenance will be covered in more detail in the next H2Grow blog post, this will include a checklist that you can download and print off to help you with this task.

Keep an eye out for the next post or subscribe by entering your email in the box to the top right of the screen to ensure that you don't miss it!

Today's blog was written by Sarah Elliot from Lindsay NZ - I hope you have found it useful!

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

EM Surveying - The Uses

In the previous EM survey blog, I ran through the process of conducting the survey, this time I will go through some of the uses.

The data from an EM survey is very useful for irrigation in many ways. The topography data can be used for planning the pivot design itself with your irrigation provider for example working out tower spacing and pivot positioning. The angle of slope can be used to see if the pivot stays within design parameters for insurance purposes as well as design planning.

Figure 1: Contour map on top of elevation map

After the initial pivot or irrigation design plans, we can then look at the EM data itself to determine the amount of variability within the surveyed area. Within the PCT Gateway software we can look at the value and amount of the crop being grown on the area and the cost of installing variable rate irrigation (VRI). The software needs to know the average yield and value of the crop. That way using algorithms it calculates that by not over watering the heavier soli types or under watering the lighter areas you bring the crop yield on those areas up to the average. It looks at the reduction in variability by using VRI as opposed to a blanket application. In the example below the variability from using VRI drops from 30.4% to 4.68%. So, by using the average yield and the price we can see the payback vs the cost of putting VRI on your pivot.

Figure 2: Illustrating the payback from VRI, using an EM map. 

This model just looks at the costs vs savings of VRI from a production prospective. It doesn’t take into consideration savings from reduced water use, power savings, reduced track repairs etc, which will be in addition to this.

The next stage is to make VRI maps up for the pivot, using the different soil zones, predominately we use the shallow EM results. If the area has a lot of variation in topography we can also combine the elevation layers with the EM map to make an application map for the pivot. We can also use other elevation layers to achieve the best solution used for each specific survey, as required.

The map below, shows a three zone EM map, where  red is the lightest soil, green the medium textured soil and blue the heaviest soil. This has been combined with the slope map, where the darker tone indicates a slope of 0-5% and the brighter tone of colour areas where the slope is above 5%.

Figure 3: An EM map and slope map combined to make a VRI application map. Brighter red, green and blue indicate slope for the different soil zones. 

The EM zone maps can also be used for irrigation pod placement, as well as moisture probe placement. If you only have one probe under an irrigation management zone, you want to make sure its under the right area. I will discuss this in more detail in the next blog. In the meantime, if you have any questions about EM surveying please get in touch.

Chris Smith

Operations Manager Agri Optics NZ Ltd.

EM Surveying - it's that time of year again!

With all the early season rainfall we've had the EM Surveying season has started a lot earlier than most years. It's great in a couple of respects: 1) we can get across the ground before it all gets really wet (if that happens) and the potential to make a mess increases and 2) it gives you more time to analyse and incorporate the data into your decision making over the winter months. 

As we're already into it this year, we thought it was time to give you a reminder about EM Surveying and how it all works. Today you'll get the first of a two part blog looking at the process, what you get from an EM Survey and what it can all be used for. 

EM Survey – Part 1 - the process.

When we conduct an EM survey we are measuring the electrically conductivity within the soil profile, the values have close links to the soil texture properties, where clay gives a higher reading than silt that in turn gives a higher reading than sand. So, by driving over a block of land you pick up the differences in the soil texture at two different depths 0-50cm and 0-125cm. Other factors have varying degrees of influence on the readings such as soil bulk density and moisture within the profile at the time of the survey. High salinity readings can have a huge influence on readings, but this is only in specific areas of New Zealand. The EM data is logged using 2cm accurate RTK GPS, so not only do we map the relative changes in soil texture, we are also collecting valuable topography data at the same time.

Agri Optics' EM Survey setup with soil profile shown. The measurements penetrate 1.25m into the ground. 

We drive most commonly at 12m swaths across the area, but closer resolution can be used for more intensive situations such as viticulture. Once the survey has been conducted we write a report about the findings from the two different EM layers, we then zone the EM data up into different management areas and run topography generated maps. Once you have had time to read through the report we arrange a meeting to then run through the report with you in person if you so desire. We also supply the client with software to view the data on their own computers and look at the different layers plus make your own management zones if required. From this point we can then focus on the areas of interest for your requirements.

The survey data has many uses, depending on the farming type and location and includes but is not limited to the following;  being the basis of variable rate irrigation application maps, moisture probe placement, used in zonal soil sampling, in dryland farming areas knowing where to put your effluent, to varying your nitrogen use depending on the underling soil types and used for flood modelling. It can also be used in conjunction with other layers of data such as yield maps, biomass maps and as happens frequency used with the topography data. Over the next few blogs I can drill into more detail on these different uses.

The EM season runs form the end of irrigation in the autumn through to Spring, but from now onwards is the ideal timing. For more information on EM surveying or to book one in for this season, please contact one of the Agri Optics team. Cheers, Chris. 

Technology Transforming New Zealand Irrigation

The latest issue of the IrrigationNZ News (Spring 2017) features an excellent and in-depth article on how technology is transforming irrigation in New Zealand. Featuring six case studies from throughout the country describing the different technologies applied on each farm - from soil moisture sensors to weather forecasting options to automated irrigation systems "designed to deliver the right amount of water at the right time".

Many of the technologies discussed have been previously showcased on our H2Grow blog so if you are interested to find out more follow this link and turn to page 28 => IrrigationNZ News: Spring 2017

Overlooking the North Otago dairy farm run by Nick Webster part of the "Peter Mitchell and Nick Webster" case study discussing how they use Growsmart Precision VRI technology to improve their operation.

Shared by the H2Grow team.

The Ultimate Add-On for Cost Efficient Irrigation

Growsmart Precision VRI with FieldNET is the ultimate add-on for easy and cost efficient irrigation, Maniototo sheep and beef farmer Hamish Mackenzie says.

“It’s simple, easy to use and gives you heaps of flexibility. I can sort and upload a watering plan and set it going at the push of a button,” Hamish says.

Hamish Mackenzie uses Growsmart Precision VRI to apply the right amount of water, in the right place at the right time at Kyeburn Station

At Kyeburn Station, an extensive 3300ha sheep and beef property, 260ha of flats are irrigated. Half the area is watered by a 570 meter Zimmatic centre-pivot. It was installed with Growsmart Precision VRI in 2015 and in November 2016 was upgraded with FieldNET, a remote communication tool making it possible to control Growsmart Precision VRI from any internet-capable device. The limited cell phone coverage means Hamish is not set up for complete remote control but FieldNET has given him greater flexibility over irrigation. And he says the new updated system is far superior to its predecessor.

“I do all of my irrigation plans on the home computer. If we had reliable cell phone coverage I’d be able to send them remotely to the pivot but because we don’t I put them on a memory stick which I then plug into the pivot panel of the irrigator. It’s really simple and straightforward.”

The touchscreen panel allows farmers to easily make changes to irrigation plans out in the field.

This season the pivot watered 37ha of Relish red clover-based pasture; 28ha of lucerne; 12ha of barley; 17ha of swedes; and 7ha fodder beet. The patchwork of different crops, each with different watering requirements throughout the season could have made irrigation planning and management a headache. But the combination of Growsmart VRI and FieldNET made it surprisingly straightforward.

“You can add in as many different fields as needed, and alter the watering rates on each or keep them out of the rotation as required. That’s the beauty of VRI and FieldNET, it’s so easy to alter things.”
Installation of FieldNET was about $1,000 on top of the Growsmart VRI but he reckons he’s easily recouped the cost – and saved water. Efficient use of water is a number one priority given the region’s 500mm annual rainfall and extended summer dry periods.  Water is taken from the Kyeburn River, from a main race which Hamish shares with four farms. He has a 52l/s allocation but over the last year the combination of Growsmart Precision VRI and FieldNET has reduced pivot water use to about 43l/s.


“I’ve been able to cut back the percentage flow through the pivot in summer and we’ve been able to use the extra if needed for k-line irrigation. Also we’ve saved money because we’re not having to pump as much water and we don’t need as much pressure.”

Irrigation development at Kyeburn Station started after completion of tenure review in 2009.
“We surrendered 4700ha of hill country to the Crown in 2009 so we had to intensify what we were doing.”

The goal was to maintain the same number of stock units by ramping up production on flat country. They purchased some neighbouring land that was irrigated, and added another 100ha pivot. There is now 260ha under irrigation, of that 180ha is covered by two Zimmatic pivots, one of which has Growsmart Precision VRI and FieldNET.

“I will sometime in the future retro fit the older Zimmatic pivot with Growsmart Precision VRI as well. I think it’s really important given the push by regional councils to encourage farmers to use less water and become smarter with how they irrigate.”

Lindsay NZ

'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

Event Reminder: B+LNZ South Canterbury Farming for Profit Technology Expo - August 11th

Farmers in Canterbury and North Otago don't forget to head along to the Phar Lap Raceway in Timaru tomorrow for the B+LNZ South Canterbury Farming for Profit Technology Expo.

There is a great line up of presentations including a number relating to precision agriculture and efficient irrigation. And if you would like to meet some of the connections and contributors to the H2Grow blog in person than be sure to grab a front row seat in the following presentations:

4pm - Variable rate irrigation and the latest irrigation technology from Lindsay, manufacturers of Zimmatic, Growsmart and FieldNET irrigation solutions.

4:30pm - The benefits of EM surveying and precision agriculture products and services offered by Agri Optics NZ.

For full details of the agenda click here.

... and I will give you a heads up that H2Grow will be kicking off an exciting competition from 1pm tomorrow. Entries can be made at the Technology Expo and online, so head along tomorrow or watch this space for more details!!

From your friendly H2Grow Team

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 2 of 3)

In the last blog post we looked at nutrients and how Precision Ag can help with your Farm Environment Plans (FEP). This blog post looks at how an EM survey can help with identifying your soil types for your Farm Environment Plan.

An EM survey illustrates the relative variability in soil characteristics including soil texture that can be potentially related to water holding properties within that soil profile, this can help you manage water application through the use of variable rate irrigation technology. When combined with the use of soil moisture probes you have the data and technology you need to be able to retain nutrients within the soil profile itself. 

EM surveys can be ground-truthed to find the correlation between the EM value and water holding capacity (WHC).  From that you can create a WHC map and site-specifically place moisture probes to monitor the soil moisture levels within each identified zone.

Ground-truthing sites are identified within each zone (shown on the left). The graph illustrates the correlation between the EM values and WHC in the top 55cm of the soil profile for this paddock.

In the image above we can see the correlation between EM value and WHC at this site has an R2 of 0.97 (R2 quantifies goodness of fit. It is a fraction between 0.0 and 1.0, higher values indicate that the model fits the data better). We can then use the equation in VA Gateway, one of the PA software platforms supported by Agri Optics, to create a water holding capacity (WHC) map out of the EM values map.

The EM map converted into a Water Holding Capacity map

This water holding capacity map can then be used in conjunction with soil moisture probes and VRI to maintain the moisture levels between field capacity and critical moisture. This not only reduces any potential yield loss from moisture stress but it also ensures that you aren't saturating the soil profile, and therefore avoid leaching nutrients out of the root zone.

It’s all about balancing crop requirements, real-time moisture levels, rainfall (when it comes!) and application rates with irrigation return times as precisely as possible to keep everything at an optimum level.

An AquaCheck soil moisture probe graph showing soil moisture levels and how they are affected my irrigation or rain events on this soil profile.

As can be seen above by keeping the moisture between upper and lower readily available water levels you ensure yield isn’t compromised and eliminate leaching. The rooting depth used for the probe profile can be tailored to the crops specific needs on the moisture monitoring website.

Next time we will discuss how the EM maps and topography data can help you with your FEP.

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

FieldNET and EM Surveying. The Ultimate Moisture Management Solution.

Electromagnetic soil surveys (EM) and variable rate irrigation are two tools that when used together can have maximum impact on your bottom line and allows for optimisation of the VRI system. On top of this, systems such as the Lindsay Precision VRI and FieldNET can produce a proof of placement map which can be used for analysis with other layers. This feature adds to the power of the EM-VRI combo.

The EM Survey:

• From the EM survey individual zones of soil type can be created, each with different water holding capacities.
• Zone maps are geo-referenced which allows for further use in mapping programs.
• Ground truthing of EM zones with a neutron probe will build a profile of actual soil water holding capacities.

EM Survey Zones

The VRI plan has multiple features:

• Each soil zone has been added to have a different irrigation rate.
• Tracks have been set as avoid zones. Troughs and low points can also have variable rates.
• Pivot wheel tracks have a reduced irrigation rate.

FieldNET VRI Plan

 Once the plan has been run the FieldNET software will calculate the total mm of water applied over a given time period. This produces a map layer that can be used to further investigate relationships with other data layers such as yield data. The proof of placement map serves as excellent reporting tool as the total amount of water applied to each zone on the farm can be accounted for. It is important to remember that the combination of EM and VRI allows for greater precision and ultimately greater efficiency.

FieldNET VRI as applied map:

• Irrigates to a set plan which can be dictated by factors such as soil moisture conditions, crop growth stage and available irrigation water.
• Produces the record of water applied. This can be broken down further into water applied per zone. The reporting features enable accurate proof of water applied.
• If a cost is applied over the water applied map a cost per zone can be quantified.
• Further analysis can then be done on gross margin per zone with the cost of water applied factored in. Stay tuned to the blog to see the latest on this front.

FieldNET VRI as Applied Map

Data from irrigation proof of placement maps can be fed into OVERSEER®. The total amount of water applied can be used at a block level. This has in recent cases reduced leaching values at block level. It shows that there is merit in capturing this information and that there is potential for multiple uses for the data in the future. 

For more info see http://www.precisionirrigation.co.nz/en/pages/products/?content=7

Another post from Nick, Precision Ag Technician. 

Managing Pivot Wheel Track Problems

While centre pivot track management is fairly routine for most growers, those working in more challenging paddocks often need to take extra measures to avoid creating deep tracks or getting stuck.

“During the design phase of a centre pivot is the most cost-effective time to manage tracking issues,” said Steve Melvin, Irrigation Applications Specialist with Lindsay Corporation. “However, there are steps growers can take at any time to help reduce tracking problems.”

Following good maintenance practices is the first and most cost-effective step in reducing tracking problems. Melvin suggests:

• Check the owner’s manual and adjust the tyre pressure accordingly. When the pressure is too high, the tyres will make deeper tracks and if it’s too low, the tyre may come off the rim.

• During the first pass of the year, run the pivot around dry on a day when the soil is fairly moist but does not stick to the tyres or squeeze out. These conditions are optimum for packing the soil in the wheel track. During the second pass, apply 6 - 12mm of water. This will help compact the soil and reduce the depth of the pivot track during the season. 

• Over-watering and keeping the irrigated area too wet often leads to deep tracking problems, so it’s important to maintain a good irrigation schedule. Apply the largest practical irrigation depth, without runoff, and allow the paddock surface to dry more before the next pass. 

In areas where conditions create significant problems, Melvin said growers have additional options, including:

• Adding a three-foot extension in the pivot pipe at the pivot point every other year, which allows the wheels to move out of the old tracks for a year. This gives the soil an opportunity to firm up before moving back the following year.

• Adjusting the sprinkler configuration around each tower to direct water away from pivot tracks or applying water after the pivot has passed.

• Integrating Variable Rate Irrigation technology (VRI) for pinpoint control of irrigation systems. With VRI technology, problem areas can dry out, reducing the depth of the tracks throughout the growing season. For more information visit growsmartprecisionvri.co.nz.

• Increasing tyre footprint by switching to larger tyres, NFTrax or radials to minimise the kg's per square centimetre the wheel puts on the soil.

To access the complete article that Melvin wrote about track management options, visit www.ksre.k-state.edu/irrigate/oow/p16/Melvin16.pdf.

For information about tracking solutions, including NFTrax, talk with your local Zimmatic dealer or visit www.zimmatic.com/tracking-solutions. 

This helpful guide to managing wheel track rutting has been adapted from a recent Zimmatic by Lindsay blog article (Managing Wheel Track Problems) and posted today by Sarah Elliot from Lindsay NZ.

Efficient water management = successful cropping season

The 2015/16 cropping season saw a year that required a large amount of irrigation across most of the country due to the dry weather. If you weren’t using spray irrigation, variable rate irrigation (VRI) or measuring your soil moisture you probably ended up either over or under-doing the irrigation required for your pasture or crops. The more efficient an irrigation system, particularly this season the better off you would have been with maximising your return times and applying the right amount of irrigation for each crop.

Following harvest for the cropping guys we’ve certainly seen that more efficient irrigation methods (pivots and laterals and VRI) coupled with soil moisture monitoring has resulted in both increased crop yields as well as more even crops, even in this tricky dry year that we’ve had.

At Greenvale Pastures this season Craige Mackenzie has seen a massive advantage in his investment in spray irrigation (1 pivot and 1 lateral) both with VRI and his soil moisture probes. Average wheat yields have been up approximately 3.5t/ha this season and ryegrass yields have been up approximately 800kg/ha. These quite large yield increases during a testing dry year show that good yields are highly achievable and in Craige’s case, that Precision Agriculture (PA) and the tools and technologies that are part of PA are helping him achieve this.

Wheat yield map - 2015/16 season

Assuming that 50ha of a farm was in ryegrass and 50ha was in wheat with these yield increases it would give an increased profit of $64,750 (assuming wheat is $370/t) for wheat and $100,000 (assuming ryegrass is $2.50/kg) for ryegrass. This averages an increased profit of $1,647.50/hectare. When put into perspective this increase in yield is enough to almost pay for a pivot a VRI system and EM Surveying in one year.

The other advantage of using VRI on cropping farms is that you typically get a more even crop which makes life far easier when it comes to harvest as the entire crop is mature and ready for harvest at once. This advantage is very hard to tie an actual cost/benefit value to however the feedback from cropping farmers to date is that this is worth a significant value to their enterprises and this differs from crop to crop.

Wheat (Starfire) on 7th January 2016 - Paddock 19 @ Greenvale Pastures

The challenge from here is to see how we can consistently keep these yields up for all crops and across all seasons while maintaining strong on farm profitability. From where we’re placed and with the experiences we’re having across a wide range of farms we see Precision Agriculture as the way to do this. It’s all about knowing your paddocks and your crops and mitigating the weakest limiting factor and working from there. For some it might be fertility, for others it might be variable soil types and irrigation but for all cropping farmers yield mapping should play a key part in this Precision Ag journey.    

Here’s a photo for a bit of yield motivation…what can you achieve in this coming season? 

Great yields in wheat - 2015/16 season @ Greenvale Pastures

You can also see more of what’s happening on farm at Greenvale and keep up with their progress on their Facebook page https://www.facebook.com/Greenvale-Pastures-Ltd-135453169954919/

If you have any questions on how you can get the most out of your yield data or where to start the Precision Ag journey please give us a call at Agri Optics (03 3029227) so we can help you get started in the most efficient way for your farm. Cheers, Jemma

Irrigation NZ Conference Summary

The Irrigation NZ Conference was held in Oamaru from the 5^th to 7^th of April. There was a huge range of speakers and presentations all relating to different aspects of the industry. Some of the important and recurring topics are summarised below.

Irrigation has benefits to communities and the environment.

The pre-conference tour took a bus load of delegates on a tiki-tour through the Waitaki valley to see first hand the irrigation schemes that draw water from the mighty river. It is readily apparent that irrigation water has benefits to farmers and community.  An example being a storage pond which is held in a trust to allow the public to use it for recreational use. A great example of the community and irrigators coming together to prosper together.

MGI Intake off the Waitaki River.

Also highlighted on the trip was how irrigation can have benefits to the environment.  The frequent droughts experienced by the Waitaki Valley prior to irrigation meant that rabbits and dust storms were free to wreak havoc on the area. Now, with irrigation, soil is no longer lost in howling Nor’Westers and improved soil structure has resulted in reduced sediment loadings in water ways. This draws some similar parallels to Keith Cameron’s talk at the PAANZ Conference (see: http://www.h2grow.nz/2016/03/inaugural-paanz-conference-summary.html)

The future is a scary place…

Synthetic meat and massive urban greenhouse skyscrapers are set to be realities in the future. The value and limited supply of the world’s natural resources was something that really hit home in Julian Cribb’s talk and it gave serious weight to the fact that efficient irrigation and water use is extremely important.

Another guest speaker, Peter Biggs detailed the concept of the volatile, uncertain, complicated and ambiguous world that we live in today. Complexity and uncertainty are two concepts that are a big part of the irrigation scene in New Zealand. How do we keep an eye on the future when such complex issues confront us at home on a daily basis?

Engaging with the public is important for success.

Nicky Hyslop, Chair of INZ made us aware of something we are all possibly guilty of. Not listening when we should. The idea that more often than not we just need to “shut up and listen” when dealing with the public on issues related to irrigation and agriculture and go forward in a dynamic, proactive way. The key message being that we must “engage” with the public rather than lecture them if any change is to be bought about.

 

Waitaki Irrigators Collective to bring together all irrigators in the Waitaki Valley

Management and measurement to improve efficiency.

The growth of technology in the sector is seeing efficiency gains left, right and centre. From improved efficiency of infrastructure that delivers water to the farm gate to the use of VRI and soil moisture management, irrigators have plenty of scope to lift performance. The level of data that can be easily captured from an irrigation system such as; flow, pressure and energy used is high. Not only can irrigators make use of this data to reduce energy costs but also water use efficiency. Dan Bloomer presented on how simply it is done with 2 dozen buckets to actually measure what water your irrigator is putting on the ground. Ultimately what gets measured gets managed.

This weeks post was bought to you by Nick Evans of Agri Optics. To find out more about Nick or to get in touch with Agri Optics check out our website: http://www.agrioptics.co.nz/meettheteam/ 

Inaugural PAANZ Conference - Summary

Precision Ag in New Zealand is finally starting to gain a bit of traction in NZ & this was seen last Friday by:

1)      the fact that the Precision Ag Association of NZ (PAANZ - www.precisionagriculture.org.nz) ran their first conference

2)      the  number of attendees that came from far and wide to attend & learn

Firstly, I’d like to congratulate the PAANZ committee on organising a well-run event with some thought provoking topics and speakers. I’m going to run through a bit of a summary of the day in terms of what was covered and some ideas to ponder.

Andy Macfarlane from Macfarlane Rural Business kicked the conference off to a start with a general overview of NZ ag and where we’re at in terms of water, nutrients and farming within limits. One of the key points from his presentation was that “Good Management Practice (GMP) is a given – everyone needs to get there NOW!” GMP will evolve and is not a fixed point. ‘Good’ will also not be good enough, farmers will need to be ‘great’ to keep ahead of the game and ensure long term farm viability. Precision Ag is going to be integral going forward to achieving this.

Some Key Principles for mitigating N leaching

1. Measure before you apply – need to know what you’re dealing with so you can make the right input decision.
2. Use nitrogen (& water) interceptors – roots, different crops etc
3. Smaller and often applications are better than large amounts and less often
4. Do not put nutrients where you don’t need them (use targeted application technology – Precision Ag)
5. Apply less urine or less nitrogen concentration in urine
6. Increase nitrogen utilisation in gut to decrease output of nitrogen
7. Less water drained = less nitrogen leached
8. Integrated farm systems approach required to achieve long term desired outcome
9. Validation of science needed both at research level and on farm

Keith Cameron, Professor of Soil Science at LincolnUniversity also posed a sound point that irrigation, even though it might be controversial in some areas and need better management allows increased N uptake as the plants are actively growing and not under stress, therefore less leaching of nitrogen results. Is there a case for environmental irrigation? Especially in summer dry areas? He also pointed out that we need to look at plant uptake as a mitigation strategy for decreasing nitrogen leaching. Catch crops following/during winter grazing is likely a good way to achieve this and studies have shown that this can be by between 20-40%.

While we all know that nitrogen itself is a key part to the nitrogen leaching discussion, in irrigated Canterbury and other parts of the South Island managing soil moisture is key to effective nitrogen management. Dr Tony Davoren from HydroServices spoke on this topic and highlighted the following:

• Measuring and understanding your soil moisture is key to good irrigation management and reduced leaching
• No drainage throughout the growing season from pivots if managed well – the same can’t be said of other irrigation systems with high application rates in particular
• You need to measure soil moisture at and below the root zone. Firstly to understand your plants requirements, and secondly to know and be able to prove that you aren't leaching and wasting water
• It’s also important to measure soil temperature as this is also a factor when scheduling irrigation and brings in the ‘farm systems approach’ that Andy talked about by looking at multiple factors.

As the focus of the day was mostly looking at how nitrogen leaching could be reduced using Precision Ag (PA) techniques there wasn't a lot of emphasis on other areas, however some were slightly touched on. These included Ian Yule (Massey University) talking about the economic impact of poor spreading pattern and that it could cost a farmer on average $45/ha if his spreading CV was at 20%, however CV was likely to be nearer 30% when out in the field. At costs like this we obviously need to get our spread pattern accurate before we start doing variable rate fert. Accuracy is key to everything in Precision Ag. The benefits of ‘All Paddock Soil Testing’ was highlighted for reducing paddock to paddock nutrient variation and pushing pasture yield along on dairy farms.

There were a vast array of topics covered during the day, stretching further than just nitrogen leaching and it was truly encouraging to see such a good turn-out of interested people to this inaugural event as well as the robust debates and discussion that went along with it. It’s truly heartening to see NZ farmers and industry pushing the boundaries and meeting NZ farming targets using tools and technologies that are already out there today. The future is very bright for NZ ag and coupled with all of the emerging technologies and the science to back these up I feel very encouraged about the position of the New Zealand farmer. Now to get everyone dabbling their toe in the water of Precision Ag…

~ Jemma