Category Archives: Precision Agriculture

Testing On-Farm Fertiliser Spreading

LandWISE 2015 Presenter, Dan Bloomer

DanBloomer200
Dan is the Manager of LandWISE Inc, an independent consultant, and a member of the Precision Agriculture Association of New Zealand Executive.

The SFF “On-Farm Fertiliser Applicator Calibration” project arose from repeated requests by farmers for a quick and simple way to check performance of fertiliser spreading by themselves or contractors.  They wanted to know that spreading was acceptable.

A calibration check includes assessment and correcting of both application rate (kg/ha) and uniformity (CV). Farmers indicate determining the rate is reasonably easy and commonly done. Very few report completing any form of uniformity assessment.

There are many protocols internationally relating to the spreading of fertiliser products. Lawrence (2007) compared six test methods.

1400 tray matrix used to collect 18 simultaneous transverse tests on a Transpread “W” twin chain spreader From Lawrence, 2006
1400 tray matrix used to collect 18 simultaneous transverse tests on a Transpread “W” twin chain spreader, From Lawrence, 2006

Most used 0.5 m trays organised in a single transverse row to capture the spread pattern of the spreader. No account is taken of the longitudinal variation between individual rows when multiple tests are carried out.

Larwnce Comparisons

The results of the test are given as the bout width where the coefficient of variation (CV) does not exceed a specified level. In all cases the maximum allowable CV is 15% for nitrogenous fertilisers and 25% for low analysis fertilisers.

An On-Farm Protocol

There is no set method dor assessing uniformity. On-farm testing could use a set number of collectors per swath (spacing changes with swath width) or a set spacing between containers (container number varies with swath width). Farmers can decide.

There are however some important principles:

  • Uniformity requires collection of samples from a spreading event and calculation of a uniformity value.
  • Set equipment up correctly according to manufacturer’s instructions
  • Ensure the spreader is horizontal, and at the correct height off the ground
  • Use standard test trays, given the need for baffling to stop fertiliser bouncing out
  • Ensure the spreader is driven well past the trays to capture all fertiliser
  • If a larger sample is wanted, two or more runs at the chosen application rate should be made rather than applying a higher rate.
FertSetUp
Set equipment up correctly according to manufacturer’s instructions
FertTrays
A line of trays laid out across the full width of spread to catch fertiliser. Use standard test trays, given the need for baffling to stop fertiliser bouncing out

Weighing samples is complicated by the very small quantities involved – often a single prill in the outer containers. Scales weighing to 0.01g are required, but satisfactory options are readily available at reasonable price.

An alternative is to assess the volume of fertiliser captured in each tray. Disposable syringe bodies make good measuring cylinders.

FertTestRack
Disposable syringe bodies make good measuring cylinders

Determining a field uniformity will involve either physical or theoretical over-lapping of adjacent swaths.

FertOverlap
Determining a field uniformity will involve either physical or theoretical over-lapping of adjacent swaths

On-line software is being developed to process data and generate statistical reports. Key outputs will be measured application rate, the CV at the specified bout width and the bout width range at which CV is within accepted limits.

Test spread-pattern checks performed to date show there is a need for wider testing by farmers. Unacceptable CVs and incorrect application rates are not unusual.

 

There remains some question about the percentage of fertiliser caught in some types of tray

The SFF project is co-funded by the Foundation for Arable Research and the Fertiliser Association

FertResearch

FAR

 

Micromanaging Your Planter

LandWISE 2015 Presenter, John Ahearn

John Ahearn
John Ahearn, GPS Control Systems

Modern planters are amazing machines.  Electric and hydraulic drives with precise speed control have replaced ground engaging wheels.

Variable rate is achieved using prescription maps.  Individual row control is achieved using GPS location. So seed populations, fertiliser rates and spray rates are accurate. Up hill, down hill, on curves, headlands, and point rows – the precise rates are applied with zero over-lap.

How do you check your new planter is performing as advertised?  Before looking for improvements we need to get a benchmark of where the performance is now. During planting there are some problems you can identify and fix on the go and some you can’t.  The trick is to record planter data, match it with yield data, and use that analysis to fix or modify the planter for next year.

Most planters have a simple population monitor but the addition of a few extra sensors, and a data management tool, gives an idea of how these variables affect your planter, and ultimately – your yield.  Variables to monitor include singulation, ground contact pressure, ground wheel slippage speed.

When you know what happened during planting, and can compare that to the end of season yield map, you can then figure out the impact these variables have on yield.  That yield impact can be converted to a dollar cost which leads to a discussion on planter improvements for an old planter, and a set-up review for a new planter.

An aftermarket planter control system can be retrofitted to most old planters.  The system will monitor and record the planter variables during the planting operation for each field.

Ideally, the same system will also be used to collect and record yield data during harvest. This completes the loop for data collection and gets all the data in the same place on the same software.  Later analysis is then simple and it is easy to identify opportunities, problems and create prescription maps for next season.

What goes on the planter?

  • Monitor /computer screen in the cab.
  • population sensors – use existing or fit newer better units
  • down force sensors and hydraulic down force control units
  • electric or hydraulic drive system for seed, fertiliser, and other inputs
  • section control

Process improvement is a continual process that leads to higher yields, reduced inputs, and higher profitability.  There are a lot of variables we can’t control, but closing the loop on planter variability finally adds some true value to your yield maps.

Monitoring peas from the greenhouse to paddock

LandWISE 2015 Presenter, Christina Finlayson

Christina Finlayson, Research Associate, Plant and Food Research
Christina Finlayson, Research Associate, Plant and Food Research

Peas grown for processing can be a notoriously variable crop both in terms of overall productivity and maturity at harvest. In turn, this can have a significant impact on paid yields and grower profitability.

Many factors are thought to contribute to variability in peas – some of which are beyond grower control and some of which can potentially be influenced through management.

In recent years we’ve worked to consider a few of these ‘manageable’ factors, and specifically, the effect of seed characteristics on early crop vigour and the response of crops to plant growth regulators (PGRs).

The aim of this work has been to identify practices that reduce plant-to-plant variability in the field and maximise paid yield returns for growers and processors.

In our talk we present results from a greenhouse trial looking at the effect of seed characteristics on early crop growth, and how that relates back to the previous pea seed crop. Preliminary results suggested that different-sized pea seed can result in big differences in early plant size and growth.

Finlayson_PeaSeedlingWeightVsSeedWeight
Different-sized pea seed can result in big differences in early plant size and growth

 

These early differences in productivity are seldom overcome, so getting a consistent ‘start’ is important in minimising future variability issues. However additional variability develops following establishment .

In the field, we have conducted several trials assessing the potential efficacy of a range of PGRs on flowering dynamics and pea yields. Across these trials we’ve seen few clear effects of the PGR types, rates and timings that have been tested.

Finlayson_PGRs

 

“V” is for variability – origins of variation within a crop and contributions to yield

LandWISE 2015 Presenter Bruce Searle

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Bruce Searle, Crop Physiologist and Modeller Plant and Food Research

Why is a crop so variable and what can be done about it? And of that variability, how much can management practices actually affect?

Those who work with crops are well aware of this variability, but ways of addressing it are less clear.

Variability affects profitability so managing it is important. The more variable a crop is, the more the yield will be reduced compared to an even crop that produces the maximum attainable yield, and so profitability is reduced.

Increasingly, the value of a vegetable crop is dependent on providing product that meets some quality criteria – initially, usually size. This means that growing to maximise yield does not always increase profitability if the crop does not meet the quality standards. If variability is high then less of the crop will fall in the grades desired by the market and so profitability decreases.

Causes of variability are complex. It starts with the variability in seed size. Overlaid on this is variability in emergence time, variability in seedling size, variability in plant spacing and effects on competition, individual variability in relative growth rate, and differences in spatial supply of nutrients and water in the field and patchiness in pest and disease.

All these factors interact in different ways. Models are an ideal way to quantify some of this complexity and provide good insight, but the large number of measurements needed and the large number of interactions to compute can limit the value of such approaches.

Here we start to develop a conceptual framework that allows the causes of variability in a field to be identified and enables the contribution of each cause to be considered. We have called this framework the ‘V of variability’.

VforVariability

 

We group causes of variability into spread of emergence, establishment, population and growth, and examine how these factors change for crops of onions and potatoes and affect the variability of size in onions and potatoes and dry matter % of potatoes. We use this to identify how much variability is manageable and the appropriate key management practices to consider.

This framework, when linked with digital information capture at a field scale, could provide a powerful tool for management of variability.

Presentation Authors: Bruce Searle, Jeff Reid and Paul Johnstone – Plant and Food Research

 

Converting urine-nitrogen into grass

LandWISE 2015 Presenter Geoff Bates

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Geoff Bates, Pastoral Robotics

Environmental pollution results, both from nitrate leaching and greenhouse gas emissions that arise from the high urea content of urine patches. This problem is possibly the biggest single threat to dairying in New Zealand. Pastoral Robotics’s solution addresses this threat whilst increasing the bottom line through increased grass growth without requiring large capital investment. This is in contrast to other methods of nitrate leaching reduction, all of which either reduce profitability and/or involve significant capital investment.

Pastoral Robotics’s solution allows the customer to increase profitability in the following ways:

  • Directly through increased grass growth
  • Indirectly through allowing the continuation of their current farming practice without additional costs
  • Indirectly through opening options to increase milk solids production within regional council-imposed nitrate-leaching or fertiliser N use limits.

The system

After the last cow leaves the paddock Spikey® is towed over the freshly grazed land detecting and treating the urine patches with ORUN®. ORUN® is sprayed only onto recent urine patches, meaning typically only 5% of the pasture has to be sprayed, a huge saving in chemicals.

Spikey® detects changes in the electrical properties of the soil caused by the presence of urine.

ORUN® is a combination of a commonly-used urease inhibitor NBPT (not DCD), and the widely-used growth-promotant gibberellic acid variant (GA3).  ORUN® greatly increases the already large amount of extra dry matter grown in the vicinity of the urine patch, and with it recovery of urine-nitrogen. The NBPT increases the lateral spread of urea out from the urine patch; the GA increases the vigour of the growth. This increase in growth covers all costs of using Spikey®.

Increased pasture growth automatically means reduced environmental losses of N – independent testing of ORUN® by Massey University indicated a reduction in nitrate leaching from urine patches of up to 50% and N20 emissions by 27-37%.

Mini-ME and Spikey

The first commercial version of the Spikey® urine detector and simultaneous treatment with ORUN® spray have been designed to be towed behind an ATV or other farm vehicle.

Mini-ME®, an electric robotic tow vehicle, is under development to eventually take over the towing role, leaving the farmer free to concentrate on his stock.

Presentation authors: Geoff Bates and Bert Quin, Pastoral Robotics Limited

Monitoring and Mapping Crop Development

LandWISE 2015 Presenter, Dan Bloomer

DanBloomer200
Dan is the Manager of LandWISE Inc, an independent consultant, and a member of the Precision Agriculture Association of New Zealand Executive.

In an attempt to understand variability in crops, smartphone photos were processed to assess canopy size. By geo-referencing such images, they can be used for spatial analysis. Preliminary results showed considerable promise and a tool has been developed.

One use is for detailed nutrient planning and variable rate application, which requires spatial knowledge of final yield. A case study of an onion crop at the LandWISE MicroFarm is used as an example. Onions have a potential yield of around 100t/ha but the mean national yield in an average year is only 35t/ha.

The onion crop was planted on 7 June 2014. Fertiliser was applied at three intervals, 2 August, 27 September and 24 October 2014. Yields before curing within this 1ha paddock ranged from 0 – 85 t/ha.

Overhead photos of the crop were taken across 18 crop beds on 1 October, 28 October and 14 November 2014. The images were processed by ASL Software Ltd to determine an estimate of ground cover. The crop was lifted on 8 January 2015 and fresh weights taken from each bed.  These final yield results were compared to the images taken during crop development.

Data collected on 14 November show strong correlation with final yield; R2 = 0.86.

OnionCover November

However, these data were collected three weeks after our final fertiliser application.OnionCover November Correlation

Photographs taken on 1 October had an average ground cover of 4.6% (range of 1.1 – 8.4%).

OnionCover November

The measurements at this stage  showed good correlation with final yield; R2 = 0.71 once one image with areas of surface algae was discounted.

OnionCover October Correlation

The October images were taken four days after the second fertiliser application, which could easily have been delayed. They were collected three weeks before the third fertiliser application.

This research suggests simple image analysis can provide early indications of final yield. It also suggests such images can provide timely information for adjusting rates and variable rate fertiliser application in onion crops.

To investigate the potential to create canopy maps, we automatically captured GPS referenced images. The images were processed to determine ground cover and displayed on Google Earth.

CoverMap Onion Map

All image capture and processing was built into a smartphone application by ASL Software. There was a strong spatial pattern that could allow variable rate application.

ASL_CoverMapThe accuracy of the smartphone GPS may be adequate for large scale assessment of crops in big paddocks. However, it was not able to correctly locate the images and subsequent ground cover factors within the correct onion bed. Connection to an accurate GPS signal is being included to better locate each image point.

We thank ASL Software for app development, the LandWISE MicroFarm sponsors Ballance AgriNutrients, BASF Crop Protection, Centre for Land and Water and MicroFarm supporters for access to the onion crop.

 

 

Hyperspectral remote sensing to assess pasture quality

LandWISE 2015 Presenter Ian Yule

Ian Yule, Centre for Precision Agriculture, Massey University
Ian Yule, Centre for Precision Agriculture, Massey University

A presentation by Ian Yule, Reddy Pullanagari, Gabor Kereszturi, Matt Irwin, Ina Draganova, Pip McVeagh, Tommy Cushnahan, Eduardo Sandoval.

Remote sensing methods are becoming much more accessible for end users in terms of access to results and the method in which they are presented. They can be developed into systems for herbage analysis which will measure every square meter of a farm or river catchment and publish the results in the form of a map, as below, rather than complex hyperspectral analytical measurements.  

The team at Massey University have been using a hyperspectral imaging tool called Fenix. It is flown in an aircraft usually at around 500-800 m above ground level and has been used to measure hill country properties within New Zealand in the first instance. The map below shows the level of ME in pasture for an example scene, but the major nutrients can also be mapped in this way.

MasseyHyperspectral

 

The catalyst for purchasing the sensor was the Ravensdown/ MPI, funded PGP project; Pioneering to Precision: Fertiliser Application to Hill Country.

The first scientific objective of the project is to map the nutrient concentration of pasture over hill country properties. The business objective is to provide much better information around the productivity of hill country in order to calculate the fertiliser requirements more accurately and improve the overall utilisation of nutrients.

Previous work indicated that significant financial benefit could be achieved from this approach. This is the first time that an imaging tool has been used and this is important because it overcomes many of the difficulties of on-the- ground sampling and then using these samples to represent the whole farm. It is basically impossible to capture the true variability of these properties from ground sampling.

The sensor detects light in the Visible (VIS), Near Infrared (NIR) and short wave infrared (SWIR) parts of the electromagnetic spectrum. This gives it the ability to determine the bio-chemical properties of vegetation that it observes. It has been shown to be a very robust technology for laboratory analysis and this new development takes it out of the laboratory and in the field.

The images captured in strips are mosaiced together in order to develop a single image for the whole area. Each pixel has 448 different layers of information, corresponding to 448 different wavebands which make up the spectral signature for each pixel. It is by comparing the spectral signature using a number of statistical techniques that the nutrient concentration within the vegetation can be identified.

The big advantages with this approach are that the results can be presented in the form of a map, information can be produced quickly with limited need for laboratory based chemical analysis. All of the complex statistical and analysis processes have happened in the background and the results can be presented with in a Geographical Information System (GIS). In a GIS environment data can be linked to decision making software which will help farmers decide on the optimal fertiliser policy for the farm.

Acknowledgement. The image was produced from a survey from the PGP Project, Pioneering to Precision: Fertiliser application in hill country, which is funded by Ravensdown Fertiliser Cooperative and the Ministry for Primary Industries MPI.

New Zealand Centre for Precision Agriculture, Massey University, Institute of Agriculture and Environment. Palmerston North, New Zealand.

Robotics and Intelligent Systems to Improve Land and Labour Productivity

LandWISE 2015 Presenter, Robert Fitch

RobertFitch2

Robert Fitch and Salah Sukkarieh
Australian Centre for Field Robotics
School of Aerospace, Mechanical and Mechatronic Engineering
The University of Sydney, NSW Australia

Food production in the 21st century must respond to significant new pressures to increase quantity and nutritional quality. Because natural resources are limited, achieving such goals must involve improvements in production efficiency. At the same time, we must engage in environmental stewardship, contend with the rising cost and diminishing availability of human labour, and reverse the steady decline in the number of farmers worldwide.

Meeting these challenges will require major innovations in technology, farming systems, and operations enabled by advances in robotics and automation.

One of the leaders in agricultural robotics research is the Australian Centre for Field Robotics (ACFR) at The University of Sydney, recognised as one of the largest field robotics groups in the world. We conduct research using both ground and aerial robots that is helping to shape the future of farms.

Our collaboration with Queensland University of Technology (QUT) and start-up company SwarmFarm addresses the issue of soil structure damage from ever-larger tractors and implements by replacing a single large soil-compacting vehicle with many small vehicles that move lightly across the surface without compacting the soil or disturbing its protective top layer.

The Ladybird robot designed by the University of Sydney
The Ladybird robot designed by the University of Sydney

The potential for robot teams is also strong in integrated weed management strategies. The Ladybird is a prototype we designed and fabricated for the vegetable industry, supported by AusVeg. Beneath the outer shell is a manipulator arm that can be used to position a variety of implements for weed control, such as tines, microwave, grit-blasting, and steerable targeted spray.

The problem of detecting individual weeds is one part of our general framework for crop intelligence, where robots perform autonomous farm surveillance (mapping, classification, detection) for crop growth and health.

SydneyRobots
Two ground robots and one aerial robot used in tree crops supported by Horticulture Innovation Australia Ltd.

The farm of the future will not simply replace manual operation with autonomous operation, but instead will adopt a systems view that coordinates all activities and draws more people into farming.

Whole-farm optimisation can be seen as ‘thinking beyond the robot’ to restructure farm operations in terms of the timing and logistics of all activities, where individual crop elements have a ‘personality’ that is accurately tracked over the crop lifecycle.

The ACFR has a long history of working in large-scale operations and optimisation with various industry partners and are now beginning to apply the resulting successful methodologies to the agriculture domain.

 

 

 

Instruments for Crop Quality Measurement

LandWISE 2015 Presenter Peter Schaare

PeterSchaarePeter Schaare, Bio-engineering, Plant & Food Research.

Peter specialises in designing measuring instruments for biological applications including non-destructive measurement technologies, optical instrumentation, spectroscopy, ultrasonics and automation. He is currently investigating laser technologies to assess the mineral nutrient status of plant material in the field.

The key to precise management of crops is the provision of timely and spatially detailed information on the factors determining yield and quality.  Instrumentation already exists to evaluate some of these factors; for example, yield monitors, nitrogen level sensors and electromagnetic soil mapping are in common use.  However, in-field, real-time measurement of other factors is proving challenging.  Peter’s presentation covers some types of instrumentation that may provide the key to more detailed information on the factors determining plant production.

Examples include thermal imaging of the surface temperature of leaves in the canopy to identify stress from water shortage or disease, LiDAR to estimate traits such as biomass, leaf area and height and visible-near infrared spectroscopy (VIS-NIR) which has been shown to be able to estimate soil pH via a tractor-mounted soil penetrator.

Plants emit particular volatiles when under attack by pests such as herbivores or fungi, or as a normal component of their metabolism and these volatiles can be used to diagnose the plant’s status. Which technology is a superbly sensitive technique?

Instruments and measurement are the key to precise management of horticultural and arable crop production systems and the farmer of 2030 will routinely use measurement technologies to guide his operations to an even greater extent than is done today.

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Technology Transfer to the Primary Sector

LandWISE 2015 Presenters Mark Burgess and  Bruce MacDonald

MarkBurgess UoA
Mark Burgess
BruceMacDonald
Bruce MacDonald

 

 

 

 

 

New Zealand’s national goals increasing primary sector exports require a significant investment in new technologies that radically optimise resource usage and mitigate impacts associated with sector intensification.  Crucially they need to be technologies that will be adopted by the primary sector.

The University of Auckland has been embracing the associated
technology challenges through a strategy that links its strengths in
life sciences, engineering, chemistry, physics and ICT with the
well-established agricultural and horticultural research institutes
throughout New Zealand and adopting a proactive approach to connecting its scientists and engineers to these sectors and their issues.

For example, ubiquitous work in UAV systems, robotics and automation technologies is now being directed to agritech issues such as pasture management and pollination.

This presentation will cover the strategies implemented to create an
agricultural lens for city scientists and present some case studies of
the research programmes being undertaken. We will present our view on the drivers for adoption.

Associate Professor Bruce MacDonald completed a BE (1st class) and Ph.D in the Electrical Engineering department of the University of Canterbury.  Bruce worked with NZ Electricity and the DSIR in Wellington, NZ, then the Computer Science Department of the University of Calgary in Canada. In 1995 he joined the Department of Electrical and Computer Engineering at the University of Auckland.

His long term goal is to design intelligent robotic assistants that improve the quality of peoples’ lives, with primary research interests in human robot interaction and robot programming systems, and applications in areas such as healthcare and agriculture.

He is the director of the department’s robotics group and a leader for the multidisciplinary CARES robotics team at the University of Auckland. He is the leader of Faculty of Engineering research theme Technology for Health, and Chairman for NZ’s robotics, automation and sensing association.

Bruce is part of a research team to develop modular robots for horticulture.  The Autonomous Multipurpose Mobile Platform (AMMP) modular robot is capable of navigating autonomously in orchards and will include vision-sensing of flowers and fruit for kiwifruit and apples in orchards and arms and grippers for harvesting kiwifruit and apples as well as fast-acting directional control mechanisms for precision targeted spraying of pollen and soft robotic handling of apples and kiwifruit.

The ‘Multipurpose Orchard Robotics’ project is a four year collaboration between Robotics Plus Ltd, University of Auckland, University or Waikato and Plant and Food Research aiming to automate the harvesting and pollination of kiwifruit and apples. (C) RoboticsPlus
The ‘Multipurpose Orchard Robotics’ project is a four year collaboration between Robotics Plus Ltd, University of Auckland, University or Waikato and Plant and Food Research aiming to automate the harvesting and pollination of kiwifruit and apples. (C) RoboticsPlus

The research is a collaboration between Plus Group’s RoboticsPlus Ltd, the University of Auckland, Plant and Food Research, and the University of Waikato.