Insight into the Relevance of Precision Agriculture Technologies in Victoria’s Grain, Dairy and Horticulture Industries
Our Rural Landscapes Key Project 2
Sub-project 2.5 Future Farming Systems;
Optimising Production & Environmental Outcomes
June 2007
Table of Contents
INTRODUCTION
BACKGROUND
- GRAINS INDUSTRY AND VARIABLE RATE AND SITE SPECIFIC TECHNOLOGY
- DAIRY INDUSTRY AND ALTERNATIVE FORAGE CROPS
- HORTICULTURE INDUSTRY
-
- Sustainable Deficit Irrigation and Red Wine Grapes
- LVDT and Sap Flow Sensors & Fruit Orchards
RESEARCH METHODS
- STUDY METHODS
RESULTS, SUMMARY AND RECOMMENDATIONS
- GRAINS INDUSTRY AND VR&SST
-
- Recommendations
- DAIRY INDUSTRY AND ALTERNATIVE FORAGE CROPS
-
- Recommendations
- HORTICULTURE INDUSTRY
-
- SDI and LVDT & Sap Flow Sensors
- Recommendations
DISCUSSION
- CURRENT PRACTICES AND PA PROPOSITION
- IMPLICATIONS FOR ORL PA TECHNOLOGIES
- CONCLUDING NOTES FOR THE IMPLICATIONS FOR OTHER PA TECHNOLOGIES
REFERENCES
Introduction
The Victorian State Government initiative, Our Rural Landscapes (ORL), commenced in 2003. As part of the overarching ORL initiative, the ORL subproject 2.5 ‘Future Farming Systems – Optimising production and environmental outcomes’ was developed ‘to provide Victorian farmers with next generation farming systems, tools and technologies which will lead to the development of sustainable farming communities and landscapes for future generations’ (DPI 2003). To achieve this, at least in part, the Department of Primary Industry (DPI) technical research staff were commissioned to develop four emerging Precision Agriculture (PA) technologies within three agricultural industries - the grains, dairy and horticulture industries.
Crucial to achieving the desired outcomes of ORL, subproject 2.5 relies on the PA technologies being adopted by landholders. To understand the relevance of these emerging PA technologies to agricultural landholders, four social research studies were commissioned. The main aim of the studies was to provide the ORL 2.5 project teams with insights into their route to market research.
In this paper we provide a brief background into the four different PA technologies. We then present a summary of the findings from our social research studies. Recommendations are made to facilitate a potential increase in the uptake of the technologies. Finally, given our findings and experience, we provide insights into some key principles for consideration of PA technology’s relevance to landholders.
Background
Precision Agriculture (PA) technologies are management tools that can assist producers to manage their farms on a site-specific basis. PA uses an information-based approach to farming that is enabled by the use of various technologies. Instead of taking a whole-farm system approach, producers using PA are undertaking a sub-system, ‘precision’ approach. This allows for different areas within a farming area to be managed at a quasi-micro level with inputs applied according to a specific site’s potential. In doing so, inputs such as nitrogen or water may be applied more efficiently and effectively. This ability is succinctly captured in the PA ‘motto’ of applying inputs at the ‘right time, in the right place, with the right amount’ (DPI 2003).
The four different PA technologies investigated were:
- Variable Rate and Site Specific Technology (VR and SST) in the grain industry,
- Alternative Forage Crops in the dairy industry,
- Sustainable Deficit Irrigation (SDI) in the red wine grape industry and,
- Linear Variable Differential Transformer (LVDT) and Sap Flow sensors in the orchard industry.
Grains Industry and Variable Rate and Site Specific Technology
Grain producers usually manage individual paddocks on a uniform basis despite variation due to soil type, topography and/or historic variation in yields. Emerging PA technologies, such as VR and SST, enable producers to apply inputs at rates which are altered according to preset maps or using real time sensors.
Real time crop sensors are able to deduce the crop’s physiology and detect early stress signals. Sensing technologies can be used to assess nitrogen status in real time. Inputs are applied to alleviate crop stress so that, for example, nitrogen fertiliser is applied according to the plant’s requirements. The greatest benefits from the application of VR and SST are to be seen in areas of high production variability.
Use of VR and SST requires investment in one or more pieces of equipment which can range from basic yield maps and computers to more sophisticated, costly systems. Sophisticated tools include real-time crop sensors such as thermal/in-crop hyper spectral imaging systems. The more sophisticated, costly VR and SST systems are attached to ‘on-the-go’ machinery, such as tractors or in some cases aeroplanes, making it possible to ascertain real time crop requirements.
For the purpose of this study the term VR and SST refers to highly sophisticated, costly equipment that includes real-time crop sensors such as thermal/in-crop hyper spectral imaging systems.
Dairy Industry and Alternative Forage Crops
Competing demands for water by various sources intensifies the pressure on irrigated farming industries to become increasingly efficient with water use. In the Victorian irrigated dairy industry, the reliance on perennial pastures as the major feed source means large quantities of irrigation water are used as perennial pastures typically require 8-10ML of water per hectare (Armstrong et al 1998). This substantial water requirement makes the irrigated dairy industry the highest agricultural consumer of water in Victoria (Linehan et al 2004, Pomfret 2000).
Research suggests that some alternative plant systems may provide improved irrigation precision because they tend to display higher dry matter yields per ML of water (or per ha) than perennial pasture (Doyle et al 2000, Greenwood 2003). However, adoption of these alternative crops has not been widespread (Armstrong et al 1998). A research study was commissioned to understand the feasibility of altering the pasture mix employed on dairy farms to include alternative forage crops (Lawson et al 2004).
Horticulture Industry -
Sustainable Deficit Irrigation and Red Wine Grapes
Despite the viticulture sector claim to be Victoria’s most water-use -efficient agricultural industry the sector remains under pressure to further enhance its Water Use Efficiency (WUE) (DPI 2004). One of the emerging WUE technologies currently under investigation is SDI. SDI is an irrigation technique which requires producers reschedule the application of irrigation water based on a crop requirement calculation rather than existing methods used by irrigators. Initial SDI studies undertaken by the technical researchers have suggested that vine crop water requirement is 30-70% less than current irrigation applications. Researchers are trialling three different deficit irrigation methods - 65%, 45% and 34% of the 100% control level. Results have indicated that an SDI of approximately 50% water deficit could be applied over one or two seasons with improvements in WUE and berry and wine composition compared to fully irrigated wines. According to Chalmers et al (2005) the economic consequences of reduced yield under SDI are offset by improvements in WUE.
LVDT and Sap Flow Sensors & Fruit Orchards
Linear Variable Differential Transformer (LVDT), together with Sap Flow Sensors, has the ability to measure fruit tree trunk shrinkage. Trunk shrinkage is an indication of the level of water stress in fruit trees. By taking into account water stress levels in fruit trees a more precise level of irrigation water can be applied. O’Connell et al (2004) state that Australian-based research has demonstrated LVDT’s potential to measure trunk diameter accurately and continuously, allowing for precise irrigation scheduling according to tree water stress levels.
Additionally, to assist in the accurate scheduling of irrigation, spatial variation of tree cover is currently being investigated (O’Connell & Goodwin 2005). O’Connell et al (2004) state that the amount of active radiation intercepted by tree leaves used in the photosynthesis process has a major influence on crop load and fruit size. Other studies have also shown that tree canopy cover has a major impact on orchard yield potential and crop water requirements (Monteith 1977). A light bar with sensors is used to measure tree canopy cover. The light bar is held beneath the tree rows so that the amount of shade is measured. The tree canopy cover measurements indicate the variation in tree canopy.
O’Connell & Goodwin’s (2005) more recent research suggests that the variability in tree canopy cover may impact on the efficient use of resources, such as water and pesticides, which in turn may affect production potential due to factors such as water stress and disease.
Notwithstanding the promising results from each of the current PA research projects the key to improvement within each of the agricultural industries under study will be the adoption of the technologies by the respective farming industries.
Research methods
As growers have spent time and effort in formulating criteria to assess whether any change they are considering will better meet their needs, they are able logically to explain their decisions regarding changes in farming practices including adoption of new technology (Kaine 2004). We used market research techniques based on Consumer Behaviour Theory (Assael 1998) and Farming Systems Theory (Crouch 1981) to assist us in understanding their decision making process regarding current practices as it relates to adoption of the PA technologies (Kaine et al 2005).
Study methods
Our research methods approach was consistent with the Kaine et al (2005) framework. We used convergent interviewing (Dick 1998) and laddering techniques (Grunert & Grunert 1995) to understand the benefits growers were seeking to determine the relevance of the various PA technologies. Convergent interviewing techniques are useful as they allow for the identification of similar and dissimilar patterns in reasoning on a topic. In addition, this technique enables the identification of the reasons for these patterns. Laddering techniques (Grunert & Grunert 1995) allowed us to systematically explore the reasoning underlying the decisions and actions of the interviewee. The value of this interview process lies in identifying common and complementary patterns of reasoning among interviewees (Kaine 2004).
In each research study we interviewed farmers from a variety of farming systems. This included growers from different regions in Victoria with varying farm sizes. Snowball sampling was used to identify potential interviewees (Sarantakos 1998). Interviewing continued until recurring patterns and themes were achieved.
Grains Industry and VR and SST
Twenty-two grain growers were interviewed from the Northwest and Southwest regions of Victoria (Figure 1). The study area was further divided into three sub regions - the Mallee, Wimmera and Southwest as there were substantial differences across the region in variables such as farm size and rainfall (ABARE 1999; DSE 2004) to warrant such division. We thought that these differences might influence the relevance, and therefore adoption, of VR and SST by farmers.
Dairy Industry and Alternative Forage Crops
The study was conducted in the Shepparton Irrigation Region (SIR) of the Goulburn Valley, Victoria (Figure 1). Twenty-four interviews were conducted with dairy farmers across the SIR. During the interviews we were determining the reasons dairy farmers used alternative forages in their farming system. For the purpose of this study ‘alternative forage crops’ refers to those that the dairy farmers who were interviewed considered to be ‘alternatives’.
Horticulture Industry
- SDI
The focus of the SDI research study was red wine grape growers because the market value of red wine grapes tends more to be driven by quality specifications such as colour and sugar levels compared to white grape varieties. Given the potential for SDI to have an adverse impact on these specifications it was important to research the response of SDI on red wine grapes.
To ensure red wine grape producers from a variety of farming systems were interviewed, care was taken to consult producers from the Sunraysia wine region in Victoria and NSW (Figure 1) with varying farm sizes, grape varieties, water rights and winery companies they supplied. A total of twenty-nine producers across the region were interviewed.
- LVDT & Sap Flow Sensors
Twenty-two interviews were conducted with fruit orchard growers within the Goulburn Valley (Figure 1). To understand the relevance of LVDT & Sap Flow sensors we asked fruit growers to describe their current irrigation management practices. We then discussed irrigation scheduling technologies that growers had already adopted.
 |
| Fig.1. Map of distribution of study areas |
Results, Summary and Recommendations
Grains Industry and VR&SST
Despite apparent differences in locations, we found that grain growers in all three regions followed a similar decision making process to determine required nitrogen fertiliser application rates. Nitrogen application decisions were derived from accumulated knowledge gained from their own experience, peer knowledge, agribusiness advice, government advice and weather. We found that while grain growers treated paddocks differently, variably applying fertiliser between paddocks, they believed there was not enough variability within a paddock to warrant differentiation of fertiliser application. Growers believed their fertiliser application decisions had proven to be successful over a number of years (Ambrosio & Linehan 2004).
When applying nitrogen fertiliser, growers were more likely to ‘over apply’ nitrogen than ‘under apply’. Growers believe that the cost of ‘over applying’ nitrogen fertiliser when conditions were unfavourable outweighed the risk associated with under applying if conditions became favourable. Growers wanted to ensure that moisture, not fertiliser, was the most limiting factor (Ambrosio & Linehan 2004).
Our results found that growers believed that there was no need to be more precise than current methods.
Recommendations
We recommend that:
- Research and development continue to determine the benefits (economic and environmental), from a grower’s perspective, to be gained from VR and SST adoption, and then demonstrating this via extension methods to growers.
- At this stage, extension activities based on encouraging the use of VR & SST should continue to aim for awareness raising rather than practice change. Given DPI research is still in the development phase, research efforts should concentrate around long-term outcomes rather than short-term route-to-market strategies.
- Future extension activities could draw on grower’s current practice of applying nitrogen at variable rates between paddocks as an analogy to raise awareness on the benefits of variably applying nitrogen within paddocks via VR & SST adoption.
The above recommendations are applicable across all three studied regions (Ambrosio & Linehan 2004).
Dairy Industry and Alternative Forage Crops
We found that dairy farmers tend to follow one of two broad strategies for the use of alternative forage crops, depending on the degree to which they relied on perennial pastures. The identified segments were:
- Pasture-based dairy farmers
- Cropping-based dairy farmers(Ambrosio and Linehan 2005)
Producers in the pasture-based segment use a feeding strategy predominantly based on the direct grazing of perennial pasture as the main feed source and use alternative forages as supplements to fill feed gaps during certain times of the year. Producers that use this strategy are more likely to substitute alternative forage crops for another crop rather than increase the area sown (Ambrosio & Linehan 2005).
Dairy farmers that have been identified in the cropping-based dairy segment tend to have larger farm areas than pasture-based farmers. Generally speaking, these dairy farmers believed that there were areas of their farm too distant from the milking area for the cows to graze directly. Hence farmers transported the forage from these paddocks to the herd. This system is termed ‘cut-and-carry’. As part of their overall feeding strategy cropping-based farmers considered perennial pasture to be just one of a number of feed options available for them to sow in these paddocks (Ambrosio & Linehan 2005).
The decision to go to a ‘cut-and-carry’ system requires substantial investment in plant and machinery and usually accompanies a decision to expand the farm business and increase herd and/or land size. Additionally, the move requires new skills and may have social implications. Therefore, decisions to shift to a ‘cut-and-carry’ system are not taken lightly given the time needed to implement the necessary changes required to operate the new farm system (Ambrosio & Linehan 2005).
Trends indicate that dairy farms continue to augment in land area and herd size. This suggests that it is likely that increasing numbers of pasture-based farmers will move to the cropping-based segment (Ambrosio & Linehan 2005).
Given the two segments have distinct feeding strategies; differing types of information are required for the diverse purposes extant for alternative forage crops use. Future research and development projects need to be tailored to ensure relevant information is available according to the differing needs of the two segments (Ambrosio & Linehan 2005).
Recommendations
A more detailed market research project is required to quantify the two segments, to understand the differences in demand for alternative forages between them and to ensure accurate targeting of extension messages to each segment (Ambrosio & Linehan 2005).
Horticulture Industry
SDI and LVDT & Sap Flow Sensors
We found that producers used irrigation water, not only to ensure the vine/tree’s survival but as a management tool. This enables them to manipulate plant growth to produce a profitable crop. Producers applied irrigation water at different rates and frequencies according to the vine/tree’s growth stage and seasonal requirements, to achieve both product quality and quantity. Irrigation management decisions were based upon producers’ experience, weather forecasts and various types of soil moisture monitoring tools (Ambrosio, Linehan & Kaine 2006).
Growers recognised that there were undesirable consequences in both under- and over-irrigating their vine/tree. We found that the growers believed that the consequences of applying insufficient irrigation water would be more detrimental to business viability, than over irrigating. We found that growers believe that adopting innovations, such as SDI and LVDT/Sap Flow sensors, would increase the likelihood of insufficient irrigation occurrences (Ambrosio, Linehan & Kaine 2006).
Growers believed that adequate irrigation levels were not a specific irrigation amount but a range. The range meant that growers could apply irrigation water with a ‘margin of error’ to reduce the risk of production losses due to adverse conditions between irrigation events. Growers were aiming to ensure that enough irrigation water was available to the vine/tree in case of unforseen circumstances such as the rapid onset of hot, dry weather, wind, water delivery and/or harvesting issues (Ambrosio, Linehan & Kaine 2006).
Growers believed they were applying correct amounts of irrigation water because the vines/trees were healthy and they were producing a profitable crop that met industry specifications (Boland et al 2002).
Recommendations
If SDI/ LVDT & Sap Flow sensors are considered to be essential for the survival of the industries, it is recommended that substantial resources be invested in research and development to demonstrate their value to producers over an extended period of time and across a range of farm contexts (Ambrosio, Linehan & Kaine 2006).
DISCUSSION
Current practices and PA proposition
In all the cases we explored none of the PA innovations were regarded by the target audience as technologies that bridged critical management gaps in their businesses. Rather, all PA technologies were seen to be replacing or ‘tweaking’ current farm management practices. In particular, we found that in all four cases producers believed that the proposed PA technologies did not provide a benefit above producers’ current practices (Ambrosio & Linehan 2004, Ambrosio & Linehan 2005; Ambrosio, Linehan & Kaine 2006).
This was for a number of reasons. First, producers did not see a need to be more precise than their current management practices (eg, the application of nitrogen fertiliser in the grains industry). Secondly, the implementation of the PA technology was seen to lead to an unacceptable risk to farm management (eg, using SDI in the wine grape industry). Consistent with Pannell (2006) we found that the over-application of certain inputs was seen as a hedge for unforseen circumstances (Ambrosio & Linehan 2004, Ambrosio & Linehan 2005; Ambrosio, Linehan & Kaine 2006).
We found, consistent with Kaine et al (2005), that the relevance of the PA innovation to producers is determined by the farming context in which producers operate. By ‘farming context’ we mean the farming practices and the resources used by producers to carry out the farming business and the biophysical and economic factors to which they respond (Kaine 2004). All innovations need to be incorporated into an existing farm context. Relevance can only be achieved for a given technology if it provides a benefit in a particular farming context. Below is an example of the importance of context to VR & SST (Ambrosio & Linehan 2004).
Nitrogen fertiliser is applied at strategic times throughout the year depending on a plant’s growth stage. Grain growers apply nitrogen to meet plant requirements but also apply nitrogen for future plant requirements. Growers believed that if sufficient moisture was available the plant would grow and under these conditions, the more nitrogen available, the greater the plant growth. Since prediction of rain events are inconsistent most farmers believe it is better to apply a little more nitrogen than may be required. Rather than displaying a more conservative approach and potentially risk missing out on the benefits of a rain event, growers work towards the anticipation of a beneficial rainfall event occurring.
This suggests that producers’ current operating farm context does not require use of sophisticated technologies, such as VR & SST, to determine precise nitrogen application rates. The notion of fine tuning nitrogen application is inconsistent with producer’s use of nitrogen to leverage rainfall benefits.
Implications for ORL PA technologies
In all cases, except alternative forages, we found that the proposed benefits of the PA technologies were not currently being sought by the growers. Growers did not see net benefit from PA adoption. Although currently no need exists for the PA technology this does not mean that producers will not change their farming methods in this direction in the future. Additionally, it does not mean that growers’ current perceptions of risk or benefit are necessarily correct. However, encouraging adoption will require altering these perceptions.
To assess the benefits of PA the fit of specific technologies with identified farming contexts needs to be analysed. Commonly, in our social research, it has been revealed that producers judge the aspiration for precision in input application to be, in effect, naive given the variability they face in the supply of other inputs, notably water and high temperatures. To the extent that this perception is wrong, and that benefits are available without disrupting their strategies for managing input risk, extension efforts designed to explain this could prove to be effective.
In the case of alternative forages we found that they are considered by dairy farmers to be an important part of their business. But their use was for productivity gains rather than to be more precise with water usage. This means that dairy farmers are likely to continue to use alternative forages but are more likely to continue to adopt them for productivity reasons rather than for ‘precision’ in water usage. Promoting the use of alternative forages on the basis of productivity gains can be used by the ORL project team to advantage unless the use of alternative forages in this manner is contrary to the outcomes desired by ORL investors.
Concluding notes for the implications for other PA technologies
We believe our research findings have implications not just for the PA technology under study but generally can be applied to other PA technologies. Some key points for consideration when thinking about the adoption of PA technologies include:
- For a PA technology to be adopted it must provide a benefit to the landholder above current management practices. Importantly the benefit and the level of advantage used to inform adoption decisions will be determined by the landholder.
- It is important to understand the circumstances in which greater precision in farm management practices will be perceived as beneficial by landholders. Conversely (and implicitly) it is important to understand the circumstances in which there is no benefit to a landholder in being more precise in their farm management.
- Consistent with Kaine et al (2005), the farm context will be the key determinant dictating the net benefits a landholder will perceive from an innovation when considering a change in farming practice.
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Disclaimer:
This publication may be of assistance to you but the State of Victoria and its employees do not guarantee that the publication is without flaw of any kind or is wholly appropriate for your particular purposes and therefore disclaims all liability for any error, loss or other consequence which may arise from you relying on any information in this publication.
Acknowledgements
Many thanks to all producers who were interviewed providing the ‘guts’ of this report. Thanks also to Wendy Hopkins, Ruth Lourey, Kevin Kelly, Dr. Kerry Greenwood, Dr Alistair Lawson, Dr. Peter Doyle, Geoff Kaine, Sonia Wakenshaw, Helen Murdoch, Andrew Whitlock, Dr Elizabeth Morse-McNabb, John Weber, Susan Barker, Fiona Johnson, Yasmin Chalmers, Jenny Treeby, Dr Nicole Dimos, Rosie Hannah, Kristen Pitt, Dr. Mark Krstic, Dr. Bob Belford and Professor Pasquale Sgro.
Authors: Cinzia Ambrosio and Chris Linehan
