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Rachael Whitworth, NSW Agriculture, Griffith - Michael Pfitzner, Chairman - Griffith
The Rankins Springs CWFS trial site came about as farmers in the area were looking for ways to improve their environmental and economic performance but were confused by the variety of different ideas and methods being advocated, many without substantial or validated research to back them up. The group decided to do their own research and set up a large scale trial to compare the performance of the different systems in the local environment. A conventional farming system in the district was trialed against alternative approaches to farming including organic, biological farming system and soil management systems. The aim was to determine the strengths and weaknesses of each system, and what works best in local conditions.
The trial compared crop performance - mainly yield and grain quality; financial performance - as measured in Gross Margin calculations; and environmental and biological impact as indicated by detailed testing of grain and soil designed to distinguish any environmental or biological differences between the different systems over the life of the trial. The trial also gave each system the opportunity to validate their claims in a controlled field environment. Gross Margins will ultimately tell the commercial story, with the difference in inputs of the various systems one of the biggest factors.
BACKGROUND:
The Rankins Springs CWFS trial site was set up in 2000 to primarily trial alternate farming systems over a 5 to 10 year period. It was designed with a strong focus on sustainability, with 2 main parts including environmentally sustainable and economically sustainable.
The site is located opposite the gates of "Wattle Park”, down Anderson’s Lane, off the main Rankins Springs road. The annual rainfall is around 400mm, with a growing season rainfall of 250mm.
The soil type of the site is a red loam with a pH of 4.9 (CaCl2), organic carbon 1.3%, CEC 12.32 meq/100g and a Ca:Mg ratio of 3.04. Paddock history includes canola (1999); oats (1998); wheat (1997) and wheat (1996).
The best determinant of each systems success will be the quality and quantity of grain produced, as well as gross margins and net return. There are seven systems involved in the trial as outlined below.
1. Conventional system: This system represents local district practice so is based on decisions farmers in the district would normally make when growing their own crops. This includes decisions on fertilisers, chemicals, tillage practices and overall crop management, with an overlying emphasis on the economics of each operation.
2. Albrecht: focuses on achieving a balance of nutrients in the soil. The system is based on laboratory analyses, from which detailed soil analysis and plant tissue analysis recommend specific fertiliser applications. It aims to correct and raise the overall soil fertility to improve and maintain yields and/or crop quality.
3. Soil Management Riverina: focuses on achieving a balance of nutrients in the soil. Is a local farmer owned company which provides an agronomic consultancy service to assist farmers in the wise use of fertiliser and chemicals to create sustainability and improvements in production. Soil Management realises that the soil is not a readily renewable resource and by balancing inputs we can improve quality and quantity of production. This consultancy service includes detailed crop planning, fertiliser & chemical recommendations, soil and plant tissue testing, interpretation of results, sourcing requirements from a range of suppliers and accessing latest agricultural research and trial data.
4. Alroc Mineral Fertilisers: ALROC mineral fertiliser is an organic slow release fertiliser made from a blend of crushed volcanic rocks (Basalt, Granite, Dolomite, Bentonite and Rock Phosphate). These rocks are rich in all the essential plant minerals, but in rock form, are unavailable for plant growth. Soil microbes however quickly decompose the fine rock particles into the required minerals that are used by the plants when needed. ALROC believes in sustainable and safe farming practices using nature’s own elements to remineralise the soil and improve soil management. It aims to increase crop yields while enriching the soil and not depleting them. - use organic slow release fertiliser to create a sustainable and safe farm practice.
5. Nutri-Tech Solutions: provides an in-depth fertility analysis service called Nutri-Tech Soil Therapy. Based upon the soil Therapy data prescription blends are provided, using the Albrecht style of soil-balancing combined with microbe-based biological activation. Nutri-Tech Solutions believe balance and biology are the keys to crop quality. Increased profitability is achieved through better crops, less reliance on chemicals and long term sustainability, through using natural products rather than formulated fertilisers.
6. BioAg: BioAg provides farmers with a nutrition consulting service and appropriate complementary biological nutrition products to facilitate their successful transition to and adoption of biological farming practices. It aims to balance and optimise the chemical, biological and physical properties of the soil. It uses fermented culture based products to supply soil and plants with nutrients and microbes to provide a balance and robust biological system which supports agricultural production. BioAg also uses foliar applications of nutrients and microbes at key growth stages to balance the system
7. Organic: managed as a paddock or farm in conversion to certified organic production for the first 3 years where fertility and microbial activity have been encouraged to build up through the use of crop and pasture management. This is what a farmer would have to do, in order to have a soil able to generate profitable and sustainable production, organically.
All systems, other than the organic system have been continually cropped. The organic system, for the first 2 seasons, were treating their plots as an "Organics in conversion" and used vetch to build up soil fertility levels. 2003 marked the beginning of all systems being aligned in terms of crop rotation.
RESULTS AND DISCUSSION 2000 to 2006:
2000 Overview:
2000 was the first year of the Rankins Springs “long term” alternate farming systems trial. There were limited opportunities to prepare the site in 2000 as summer rainfall was minimal. Without the ideal rain the site was disced dry, with rain falling shortly after. This resulted in a rough cloddy paddock that required a chisel plough with finger harrows at the end of March, and a prickle chain mid April after a good rain event.
The start of the season was reasonably wet but unfortunately this didn’t continue into the spring. Between the 1st September to Mid October rain was minimal. The lack of stored moisture resulted in lower than district average yields. Below are the rainfall figures for 1999 and 2000 taken at “Acres”, Rankins Springs.
Results:
Whistler wheat was sown in 2000 on 24th April at 40 kg/ha, in all systems, with the exception of the organic system, which was sown to Morava vetch in 2000. Below is a summary of the basic operations for each system in 2000.
The following table outlines the inputs and operations for each system for 2000
Yields:
Paddock preparation and seasonal conditions played a major role in determining yields and grain quality. The lack of subsoil moisture, from the dry spell late September/early October had a substantial impact. Below are the 2000 yield results.
In summary yields were relatively close in 2000 for all treatments. The Fertico demonstration yielded the best followed by Bio Ag and then Alroc. These three treatments were significantly higher yielding than the control. None of the systems yielded significantly greater than the conventional, although the Fertico Demonstration came close.
Conditions early in 2000 set the crop up for potentially good yields. With the dry spell the treatments with high nitrogen inputs suffered more in the spring, loosing their extra yield potential. The Fertico demonstration had only 10 units of nitrogen applied compared to the conventional treatment, which had 34 units of nitrogen. This may be the reason the Fertico treatment yielded the best.
Quality:
Grain quality ranged from Feed to GP1. Pinched grain affected quality, with screenings ranging from 4 to 11% in the treatments. There seemed to be a direct correlation between protein, nitrogen inputs and screenings of each treatment. The conventional and the control had the highest % of screenings as well as the highest nitrogen input. Yield potential in these treatments were reduced by the dry conditions late September/early October, as a result protein and screenings were higher. Below is a summary of the quality data for the 2000 trial.
2001 Overview:
After the 2000 harvest summer weeds were already well established (mainly melons and heliotrope) in each plot. All plots, with the exception of the organic plot, were sprayed after harvest with Roundup CT @ 1.3L /Ha. Plots were then sprayed again early March and just prior to sowing with 0.8 L/ha of Roundup Max plus 2 L/ha of Simazine. 18mm of rain followed on the 24th of April. The lupins were sown in April as a dry sowing operation and fortunately managed to get enough rain to germinate and grow prior to most other crops in the district being sown.
Plant establishment and weed counts were taken early July and given the results it was decided not to spray for broadleaves but to spray for grasses with verdict @ 75 ml/ha on the 12th July. In hindsight it may have been advantageous to spray the mustards if only to keep them in check for future crops in the rotation.
2001 was a very dry year, again putting each system to the test. There was a dry spell between April and June, which had an impact on growth and reduced yield potential. Based on neighbouring rainfall figures the Growing Season Rainfall (GSR) was 153mm, with summer rainfall 33.3mm. Total yearly rainfall was 265.5mm or 10.6 inches. Below are the rainfall figures for 2001 taken at “Acres”, Rankins Springs.
Results:
In 2001 all plot of the Rankins Springs CWFS were sown to lupins, with the exception of the organic treatment, which was still in an organic conversion phase and was sown to vetch. The difference in inputs in the different systems has been one of the big surprises for most of the local growers.
Crop details for 2001 were as follows.
¨ Sowing date of trial: April 19, 2001
¨ Seed rate: 70 kg/ha.
¨ Crop and variety: Wonga Lupins
(a mix of Popany & Blanche Fleur Vetch sown on Organic site @ 70kg/ha)
The following table outlines the inputs and operations for each system for 2001
Yields:
2001 was a very dry year, once again putting each system to the test. The dry spell between April and June had an impact on growth and reduced yield potential. The lupins were sown in April as a dry sowing operation and fortunately managed to get enough rain to germinate and grow prior to most other crops in the district being sown. Below is a graph showing the yields of the different systems in 2001 and a table with the analysed data.
In summary yields in 2001 showed some large variations. The conventional system yielded the best with 0.43 t/ha, followed by BioAg with 0.39 t/ha, Nutri-tech with 0.35 t/ha, Albrecht with 0.33 t/ha and then Alroc and Soil Management Riverina with 0.2 t/ha. The organic treatment has been run as an “in conversion to organic” system for the past two seasons. In 2003 this system will be bought in line with the structure of the other systems so as a full comparison of each system can be directly made.
2002 Overview:
2002 was a very tough year all round. Yields of winter crops were below average as a result of the dry growing conditions and harsh spring finish. Crops matured quickly due to moisture stress and the above average temperatures. Cereal crops, which were harvested, had high grain proteins, high screenings and low yields. The majority of wheat crops which were harvested in the district yielded around 0.4 to 0.6 t/ha.
The season was generally characterised by dry conditions and above average temperatures during October, November and early December and most areas in the district experienced the dry conditions from planting right through until the end of spring. The rain in mid September provided some benefit to some crops in the district but the lack of follow up rain saw crops again suffering from moisture stress.
At the Rankins Springs CWFS site Wheat was sown late June, but a lack of follow up rain after sowing meant the crop really suffered and the drought conditions, which persisted throughout the season, meant the crop was not harvested.
Below are the rainfall figures for 2002 taken at “Acres”, Rankins Springs.
Results:
In 2002 all treatments of the Rankins Springs CWFS site were sown to H45 wheat on the 25th June. There was insufficient rain to cultivate the site early on and caltrop was starting to get away particularly in the buffers so all the plots, except the organic plots were sprayed on 17th April with Roundup CT @ 0.9 L/ha. All treatments, with the exception of the organic plots were also sprayed with Logran @ 35 g/ha and Roundup Max @ 0.8 L/ha prior to sowing. The site also had an EM surveys done on it in 2002 prior to sowing, which showed little difference in soil between plots.
None of the plots were harvested due to the drought and the plots were left as ground cover for the summer. Without the crops being harvested there was no income in 2002. Below is a summary of each systems operations and costs for 2002.
2003 Overview
In 2003 the trial was in a fallow phase. All plots were sprayed early August, with the exception of the organic plots, with Roundup PowerMax. All plots were cultivated early September, with a further 2 cultivations in October and December. Below are the rainfall figures for 2003 taken at “Acres”, Rankins Springs.
2004 Overview:
2004 was again a very tough year for the Rankins Springs area. Yields of winter crops were generally well below average as a result of the dry growing conditions. Most growers sowed on the rain at the end of May. The rainfall for the site is shown below.
Results
In 2004 all systems of the Rankins Springs CWFS were sown to wheat in mid June. Crop details for 2004 were as follows.
Sowing date of trial: 17th June, 2005
Seed rate: 40 kg/ha.
Crop and variety: Drysdale wheat
The difference in inputs of the different systems remains a big eye opener for most of the local growers, and the operations inputs for each of the systems in 2004 are shown below.
There was not a lot in the yield data from last year. The highest yielding systems were Soil Management and Bio-Ag followed by Albrecht and conventional. All systems were significantly different to the organic systems which yielded 0.15 t/ha last year.
Proteins were generally high last season with the Organics having the highest followed by the conventional and soil management. The organics also had the highest screenings of 10.87%.
2005 Overview:
2005 started out as a very dry beginning to the season. The first rain allowing sowing to commence occurred on the 11th June. With the lateness of the break, and in the absence of previous subsoil moisture, it was decided to fallow the trial site in 2005 to build up soil moisture reserves for the following year. Below are rainfall figures for Rankins Springs for 2005.
2005 Rainfall 489.0mm
Rainfall April-Oct 357.0mm
Long term Average 439mm
2006 Overview:
All plots apart from the organic plots were sown dry on the 5th of May. Rain fell on the 11th June. The organic plots were cultivated and sown once weeds emerged on the 5th July. A lack of follow up rain after sowing meant the crop really suffered and the drought conditions, which persisted throughout the season, meant the crop was not harvested.
Below are the rainfall figures for 2006 taken at the site.
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