Minnipa Agriculture Centre – The Resource
MAC is comprised of a farming property, a SARDI agricultural RDE team and the Eyre Peninsula Agricultural Research Foundation (EPARF). It serves the low rainfall (<350mm annual) cereal and sheep growing areas of Eyre Peninsula – an area that represents about 12% of the total value of cereal production in the state, or about $100 million.
MAC farm is 1200 ha of calcareous light sandy loam with occasional patches of limestone and lighter risers, 1000 ha of which are arable. Approximately 75% of MAC is cropped annually.
The main function of the MAC farm is to conduct, monitor and analyse broad scale RDE programs to connect with and value add to low rainfall RDE programs. MAC conducts these activities whilst demonstrating innovative and best practice farm management practices for low rainfall environments.
The SARDI low rainfall agricultural RDE team has 21 staff based at MAC (NB: there are also some PIRSA/SARDI staff based in Pt Lincoln, Streaky Bay and Cleve that contribute to the low rainfall RDE programs on Eyre Peninsula). These staff collaborate with grower groups and conducts RDE activities across upper Eyre Peninsula from Nundroo in the west to Cowell in the east and Murdinga/Wharminda in the south.
The Eyre Peninsula Agricultural Research Foundation (EPARF) is an independent advisory group providing strategic support and planning for the MAC. EPARF is composed of elected members from the EP farming community and representatives from SARDI and the University of Adelaide. EPARF has a membership base of approximately 300 (mostly EP growers) and is an independent fundraising body for MAC programs and activities.
MAC is operated by the South Australian Research & Development institute (SARDI). SARDI is the research business group within the Department of Primary Industries and Resources, South Australia.
Historically, the major MAC investment partners
have been the South Australian State Government through SARDI, the Grains Research and Development Corporation (GRDC) and the South Australian Grains Industry Trust (SAGIT). This partnership base has expanded over recent years to include several other partners, outlined in the detail later.
As a result of the upgrade, and the continuing reputation of MAC’s quality research results, agricultural research funding bodies have strengthened their investment by supporting scientific programs aimed at boosting the profitability and sustainability of agriculture on Eyre Peninsula. $500,000 per annum has been invested for a major project and 5 new research positions under the original Eyre Peninsula Farming Systems Project (EPFS Project), which has since been refunded for another five years. There are also many collaborative research and joint commercial ventures conducted in field crop improvement both on Centre and scattered around the Eyre Peninsula that are run by Research and Agricultural staff based at Minnipa.
2005 – Present Day
Today the MAC is managed by the SA Research & Development Institute (SARDI), is the base for twenty-two staff and is comprised of:
- the research development and extension (RDE) farm
- the RDE team working across low rainfall areas of EP
- the EP Agricultural Research Foundation (EPARF).
1. About the MAC RDE Farm
The goal of the MAC RDE farm is to “maintain a farming system with flexibility to adapt to current & future commercial realities, demonstrating profitability and sustainability”. The MAC farm is 1,100 ha, of which 1,000 are arable. Between 65% and 85% of the MAC farm is cropped annually. The major crops are wheat, barley and oats, with peas and canola included when an early seasonal break permits. The remainder is a medic based pasture running 600 sheep. Rotations are varied but are mainly two years crop, one year pasture.
- Main soil type: reddish brown sandy loam, highly alkaline (pH ranging from 7.5 to 8.7).
- Average annual rainfall: 325 mm
- Average growing season rainfall (April to October): 242 mm
- Average wheat yield (10 yr rolling average): 1.6 t/ha
- Average water use efficiency (10 yr rolling average): 65%
Low rainfall farming on display
Leading edge technology is demonstrated on the farm, including emerging crop varieties, no-till cropping, inter row sowing, controlled traffic, wide row sowing, soil compaction and grazing cereals. This broad acre work is a key feature of MAC's activities and has strong appeal for farmers.
2. About the Low Rainfall RDE Programs
RDE activities managed from MAC extend across all low rainfall areas of Eyre Peninsula, with over 100 experiments established at over 20 sites. Eight research officers are based at MAC with links to experts from institutions such as SARDI, CSIRO, intra and interstate agricultural departments, and Universities both in Australia and abroad. This RDE program work is focused into several key projects:
Eyre Peninsula Farming Systems (EPFS)
One of the largest GRDC funded farming systems projects in Australia, the EPFS is the key interactive link between farmers and research. Farmer groups across the low rainfall areas of Eyre Peninsula feed priorities into the research and extension team and in turn, are vehicles for the increased adoption of new advances. Current issues being investigated are:
Plant Available Water
Accurately measuring the portion of the soil moisture available for crop growth (excluding that influenced by soil chemical and physical constraints) across a wide range of EP soils. Based on the soils measured capability, the project then researches methods to improve crop growth and water use patterns on the various soils to improve the consistency of crop yield and quality.
Improving the understanding of suppressive soils (soils with beneficial microbial compositions that can out-compete damaging soil diseases such as Rhizoctonia). Work includes a survey of EP to determine if and under what circumstances suppressive soils have developed. The project involves a PhD with the University of Adelaide to improve the understanding of disease suppression.
This is the area of the project that remains flexible to allow rapid response to seasonal farming systems constraints eg. rust diseases, insect and weed issues.
Grain & Graze, Eyre Peninsula
One of nine Grain & Graze projects throughout Australia, EP Grain and Graze focuses on integrating cropping and livestock enterprises through assessing the ‘triple bottom line’ (landscapes, livelihoods and lifestyles) of various farming systems. The project also runs a responsive RDE program, in collaboration with the EPFS.
Case studies across a range of crop/livestock ratio mixes assessing a suite of financial indicators. Results will be used in farmer discussion groups as business self-analysis tools and to help identify bottlenecks to individual business and farming system improvement.
Monitoring the components of biodiversity under different land uses. The aim is to establish a benchmark of what biodiversity exists under each land use, with a future view to identify the roles of the various organisms and how they interact to be a cost or benefit to the total farming system.
A PhD and survey to evaluate the impacts and implications of modern farming systems on rural communities, families and individuals.
National Variety Testing (NVT) & Breeding Programs - MAC staff manage the Upper EP component of the GRDC funded National Variety Testing program which tests new and current lines of wheat, barley, oats, and break crops across a range of soil types and climatic conditions.
Public and private breeding programs also target MAC as a key site for early screening of material in a low rainfall environment. Field programs to screen advanced genetic material of cereals, canola, mustard, pulses and pastures, for their adaptation to these low rainfall environments are maintained from the Centre.
Eyre Peninsula Agricultural Research Foundation (EPARF)
The management of the Minnipa Agricultural Centre has revolved around the input from two overseeing bodies. The Minnipa Agricultural Foundation, which has essentially been the fund raising arm of the Centre and the MAC Committee that had an advisory role in the running of the Centre.
In 2004 the Minnipa Agricultural Centre Committee and Minnipa Agricultural Foundation were subject to a review to enable the Centre to better position itself for the future of agricultural research on the Eyre Peninsula. As a result the Eyre Peninsula Agricultural Research Foundation (EPARF) was formed to unite the activities of the Committee and Foundation into the one body.
The main role of EPARF is to actively promote the needs and benefits of a concentrated research program on Eyre Peninsula, to attract adequate resources to undertake the programs and in doing so broaden the funding base for those, so as to ensure their security.
A bried history of annual field days
Since the establishment of the Minnipa Experimental Farm, (as it was first known), in 1915, there have been many changes in agricultural practice, but one thing has remained constant over the years.
The Minnipa Research Centre field days can be traced back to 1916, when ‘Visiting Day’ was initiated by the first Manager, Mr. Len Cook. The day became an annual event, with visitors supplying their own blankets and most of the food, and the farm providing hot water and bags of chaff for the horses.
The following is an extract from the 1926 Visiting Day notes.
The average annual rainfall at Minnipa for the years 1915 to 1925 was 14.12 inches. The cropped area of the farm has been grubbed and so practically freed of all stumps. The area cleared is 1,200 acres. The area under crop is 512 acres cereal and 54 acres to lucerne and grasses. Fallowed area is 400 acres.
Livestock on the farm consists of 49 head of horses, 12 head of cattle, 168 head of sheep and, 36 head of pure-bred Berkshire pigs.
An area has been planted to a mixed orchard. Olives, principally on the boundaries of fields, have been planted on about 60 acres. Smyrna figs have been planted on about 5 acres.
Tour of inspection
The visitors will assemble at the barn, and then journey to field No. 15. The history of this field is as follows; 1920, grubbed; 1922, burned and cropped; 1923, cultivated in April and again cropped; 1924, bare fallow; 1925 cropped; 1926, cultivated in March and again in May, drilled April 26 to May 7th and harrowed after drill. 90 lb of 45% superphosphate was applied and sown the following cereals. Barley: Prior, Shorthead & Roseworthy Oregon; Wheat: President, Merridan, Wagga 51 & Canberra; Oats: Early Burt, Glen Innes No. 5, Wilga, Kelsalls, Smyrna, Kherson, & Algerian......etc.
At the completion of the day, the party may then proceed either to the rock and water catchment or return to the homestead where buildings, stock, lucerne, orchard and other activities may be inspected.
The visiting day continued throughout the years, although during the depression years 1931-1939, the day was not held. In 1940, the farm was renamed as the Minnipa Seed Wheat Farm, and its direction changed to production of selected true-to-type seed wheat for distribution to farmers. In the 1940’s the traditional visiting day was re-initiated. By the 1947 Visiting Day notes, the extract reads quite differently;
A flock of 450 Capeedee blood Merino ewes is being maintained, with a change to Old Bungaree blood this year. All sheep on the farm have been treated with modified Mules Operation with great success. At present the farm is overstocked with horses, there being 46 of which 16 are unbroken youngsters.
An endeavour is being made with certain success, to introduce Medics into the pastures. This season 150 acres were sown to Barrel Medic at the rate of 1 lb. of seed per acre and a fair germination resulted. Two small “home” paddocks were this year sown to lucerne and a good stand is anticipated.
Minnipa Research Centre is now recognised both nationally and internationally as a leader in dry-land farming technology, and with a staff of 18, conducts co-operative research with many other research organisations including SARDI, CSIRO and The University of Adelaide.
In latter years, the field days were changed to a two-day event in September, with the field tour being retained; however trucks and buses have replaced the horse as a means of transport. Modern transport has also made Minnipa accessible within two hours from most of Eyre Peninsula, therefore excluding the need for overnight accommodation. The field days at their peak attracted up to 400 farmers over the two days, including some from other areas of the state. Today, the financial demands of modern dry-land farming have been detrimental to the number of family farms able to remain on Eyre Peninsula, therefore attendance numbers have fallen to the 200 mark.
Since 2002, the Eyre Peninsula Agricultural Foundation (EPARF) has also run an annual ‘Focus Field Day’ that featured topics of interest each year, and has proved very popular among the Foundation farmer members.
Minnipa Agricultural Centre continues to evolve, to meet the constant environmental and research needs of the Eyre Peninsula farming community. The MAC staff of twenty, makes up a large component of the small town of Minnipa, and are very active members in the community.
Description of Farm
Minnipa Agricultural Centre Farm is situated 600km by road north-west of Adelaide in County Le Hunte on Central Eyre Peninsula. The centre, which is operated by Primary Industries and Resources South Australia, occupies 1200 ha of light sandy loam with occasional patches of limestone and lighter rises. Granite outcrops are a prominent geographical feature. Minnipa Agricultural Centre serves the cereal growing (<350 mm p.a.) areas of Eyre Peninsula – an area which produces on average 40–45% of South Australia's wheat.
The main roles of the Minnipa Agricultural Centre Farm are; Broadacre demonstration of innovative, best practice, farm management practices for low rainfall environments. Build up seed of new cultivars and also produce certified seed for new cultivars being released. Contribute to the operation of R&D and extension programs projects based at the centre.
History of Minnipa Agricultural Centre
The earliest written records of the Minnipa area come from the diary of Edward John Eyre in September 1840, Eyre explored the area inland from Streaky Bay and camped on a "scrubby ridge" (Parla Peak) some 40 kilometres west of Minnipa. Later, in 1857, explorer Stephen Hack visited and referred to many of them as granite outcrops which are a prominent feature of the landscape. Pastoral leases were allocated in the area after 1878.
The agricultural development of the area around Minnipa was stimulated by the extension of the railway line from Yeelanna to the terminus at Minnipa on May 5 1913. In the following year, the Director of Agriculture (Prof. Perkins) toured part of Upper Eyre Peninsula and selected a site for an Experimental Farm. It has been a bone of contention with many farmers since that time that the Professor chose a uniform area of fertile loamy soil free of the large areas of sand and stone common to much of Eyre Peninsula. The Manager's diary was opened by Mr L.J. Cook on January 7, with the first entry - "Mr. Spafford, (supt. Expl. Work) and L.J. Cook (Manager) arrived," and on January 8 - "Explored boundaries of Section 26. Located site for temporary camp at Minnipa". During January 1915, a temporary camp was erected in the Minnipa township and levels were taken for building a dam at Yarwondutta rock.
An area of about 100 ha of grassy plain around Yarwondutta rock was cleared of bushes which were heaped and burnt, often on days when the temperature exceeded 100F ("in the shade"). After February 20, a tree puller was used to winch down mallee trees and fence posts were cut from these. Work began on excavating a water tank at Yarwondutta rock on February 27, with scoops and horses. Towards the end of March, a temporary camp and stables were erected near a small rock and claypan south-east of Yarwondutta rock.
On May 13, 1915, the Minister and Director of Agriculture visited the farm to select building sites for a "3,000 acre farm to test all branches of agriculture". A dog proof fence was erected around the experimental farm. Ploughing with a four furrow mouldboard began on July 28 - rabbits had arrived in the area by then. A cook's tent was erected, a gallery and vegetables and flowers were planted around the claypan and fenced with barbed wire in August 1915. Horses were a vital part of the development and operation of the experimental farm for many years. A horse yard, stables and a blacksmith "shop" were erected. Horses are often referred to in the managers' diary and when they wandered away, as they often did, all hands were sent to find them.
A large number of general staff came and went in the early years and are often referred to only in passing as they resigned or were involved a particular incident. Occasionally, staff became disorientated and was unable to find their way back to the camp - again, all hands were sent out to find them.
Olive truncheons were planted during September 1915 and many trees planted survive in the northern part of the Centre. It was intended that 500 acres of olive trees would be planted and that an olive press would be built at the Farm. The following is a quotation by the orchardist at the Experimental Farm before 1920, Mr. Quinn. "Our 10 acres of fruit trees have made remarkable growth. There is hardly anything better to be seen on the Murray under irrigation. I hope that an olive oil industry will be established on the Peninsula as an aid to farmers, which will prove a constant source of revenue. The Government Farm, when completely cleared will carry about 500 acres of olive trees. An oil making plant will be erected, and if farmers, as a result of our operations, can be introduced to plant olives, both for shelter and profit, we will be able to take their fruit at Adelaide prices."
More than 1,000 fruit trees of every conceivable kind were established and watered from the Yarwondutta dam. None of these trees remain today.
The following extract from the book "A History of Minnipa" by Margaret Coleman is included below as it describes some of the conditions encountered in the early years of development. An account of the farm from the Journal of Agriculture of the times follows: The Experimental Farm consists of 3,041 acres, sections 26, 27, 28 in the Hundred of Minnipa. It is fairly centrally situated and is the point from which departmental activities in agricultural matters on the vast stretch of arable land will proceed. It should serve to advertise the possibilities of this practically unknown country and should hasten the day when up-to-date farming methods are the recognised practice of that part of the State.
"Most of the farm will be arable when the natural growth is removed and consists of soils varying from light coloured, light textured sands growing broom bush and porcupine, to heavy calcareous soils with a tendency to run together and set hard, but the bulk consists of calcareous soils of medium texture growing naturally, mallee and large bushes." "There are granite and limestone outcrops with an average rainfall of about 13". The seasons close up quickly with uncertain September and October rainfall."
"A block of 50 acres was made into a reserve and is retained as such today. This illustrated the general character of the timber and vegetation appearing in the district before farming. Some of the trees of the original bush reached to 60ft. and were most attractive."
"Mr L. Cook, who had had experience in land clearing in the South-East, was asked to clear the land and start experimental work. The land was cleared thoroughly, as stumpy land was not considered suitable for experimental work."
"Horses and chains and later tractors and winches and Brown's Great Tree Puller were used on the job of clearing. The tree puller proved a most economical method for thorough clearing and several machines were later obtained. Some of the neighbouring farmers were glad to contract for the clearing work and these include A. Rowan, E. Elefsen and Leo Worth."
"Scrub was initially cut by hand using a Kelly's axe. Price for this work per acre went from 5/- to 18/- and it was considered a good day's work to have cut one acre."
"From the day of his arrival, Mr. Len Cook kept a detailed account of the events occurring and the work done on the farm, as did the following farm managers. These diaries are still in the possession of the Agricultural Centre, as it is now known, and provide a very comprehensive record of the establishment and progress of the farm and district. They not only record matters concerning the farm but also some personal details and social events within the town and district."
"Salt meat was supplied in kegs and was sent up from Port Lincoln. At this time there was virtually no livestock in the district other than horses. Workmen were paid 32/- a week and board or 8/- per day.
"Crops sown in the first year were Algerian oats, Silver King, Kings’ Red, Gluyas and Eclipse wheats, and these were all cut for hay. 148 acres were cropped and 75 acres were grubbed."
"In 1916, 220 acres were sown and from this, seed was sold to the farmers, the demand exceeding the supply. 1916 was a very unsuitable for clearing because there was not enough hot dry weather to allow the growth to be burnt, this meant weeks of work and then left much to be picked up by hand."
"The farm was experiencing difficulties at this time because most of the men were called up to serve in the war. Those who were sent to help on the farm had had no farming experience which must have made life very difficult for the manager. Only two of the men sent to the farm were old farmers, one of whom was Charlie Nottle. It must have been a very frustrating period."
"One man who had come to the farm in 1915 and then went to the war came back later to manage the farm. This was Mr Roley Hill."
"Visiting day followed the completion of the building at the Experimental Farm and this became an annual event. Visitors brought their own blankets and most of the food, and the farm provided hot water and bags of chaff."
"There was a hot north wind when "Peace Day," July 19, 1919, was declared a holiday. Mr. E. Turley rode round to all the settlers urging them to dress up for the occasion and also organised a fancy dress procession."
"The farm employed a house man and mail man who received 2 pound 5/0 a weed, and later a mechanic for 2 pound 14/0, plus keep, a week. By 1921, labourers were receiving 55/– a week plus keep and clearing was done for 55/– per acre. Mention was made of selling a beast to the butcher (T. Boylan) for 15 pounds and also buying 20 sheep for 13/3 each."
"I must pay tribute to Mr. Len Cook, who by his graphic descriptions in his diary enabled me to share the frustration and difficulties of his work and enjoyment of social outings.
- March 5 1915 A fairly warm day after a fresh dewy morning. N.W. winds light and gusty.
- April 30 Tried scoop on rabbit holes – a failure
- May 5 Started drilling oats – 6 acres dragging a long behind
- June 6 Went kangarooing – saw one dead one
- June 22 Alan discharged for cutting off mallee in lieu of grubbing after being told specifically to grub
- July 25 Drove to Pildappa rock – well pleased with lot of the country
- September 14 Crops very rusty further up the coast
- October 10 Visited by farmers Daly, Opitz Mitchell, Dunn and Christian from Yaninee
- January 3 Heavy thunderstorm at 7pm – fell for 1 hour – 70 points
- February 15 Tent occupied by Opie and Cuddle burnt to the ground with all belongings
- March 5 Early wheat to be sown with 40 lb. Super
- June 4 Mr G Lindquist held first service at Minnipa
- June 12 Grave crook pullet a little phosphate of iron syrup
- June 30 Rode to Lindquist and Lovegrove about starting a school
- September 9 Lovegrove opened tennis court at Minnipa – 20 present
- October 14 First Agricultural Bureau Meeting
- October 21 Steady rain in afternoon – tried for Wudinna – turned tail
- December 24 Xmas tree at Minnipa at night
- January 1 1918 Regatta and tennis
- June 7 Made arsenic solution for fly killer – good results
- October 22 Gave horses sulphur and Epsom salts
- January 25 1919 Got married
From History of Minnipa complied by Margaret Coleman.
The wife of the farm manager in the period 1921–1924, Mrs. R. Hill, recalled cleaning the manager's house with a shovel and wheelbarrow after severe dust storms. At times the children were taken to the top of Yarwondutta rock in an attempt to escape the dust which was often a product of regular fallowing. Water was carted by tanks on drays and the personal issue of water for each person for washing was 1 bucket per day. Mrs. Hill remembered the verandah around the Manager's house being black with flies. Butter was kept in a stone urn filled with water around it was some years before water was piped to the house. Baths were taken in metal troughs. Mail arrived on the train once each week from Port Lincoln. Bread also came weekly on the train, but most people made their own. Afghan traders sold haberdashery and gave children rides on their camels. By 1927 nearly 160 ha had been cleared completely of scrub and stumps using the tree pullers and tractor and winch, but because these methods were so painstakingly slow, axes were resorted to and in 1928, another 560 ha was cleared. From the early diary entries it is apparent that engines were notoriously unreliable and were as often under repair as not.
The geographical situation of the Centre presented an ideal situation for the distribution of cereal seed to farmers and the Centre has continued to perform this function until the present.
The Department of Agriculture publication prepared for the 50th Anniversary in 1965 describes the period to that time…….
1931–1939: Share farming Period
In the early depression years, the Government was unable to continue supporting some of the State Experimental Farms, but the Eyre Peninsula farm was retained and leased for share farming. Unfortunately during this period the farm in common with most cereal growing areas was over cropped and robbed of its fertility, and erosion resulted.
In 1940, the Department of Agriculture resumed activities on the property, but it was renamed the Minnipa Seed Wheat Farm, since cereal production was still its main function.
However, major agricultural changes took place during this phase. In many ways it could be referred to as the "rehabilitation period" in which cereal farming methods and flock management were placed on a sounder footing.
The fallow-wheat-pasture rotation gave way to fallow-wheat-oats (for grazing and grain)-pasture-pasture, which retained more plant cover and reduced wind erosion; contour farming was introduced to prevent water run-off. Particularly on fallow paddocks; replacement of horse teams by tractors had obvious advantages in timing cultivations and seeding. All these factors, contributed to improved soil stability, erosion control and crop yields.
In this period, the first barrel medic pastures were established, and these had a two-fold effect. Firstly, the pastures were bulkier and their quality improved. Then, they raised the levels of soil crop yields much further and improving soil structure.
While the medic pastures were developing, attention was given to the sheep flock.
Previously, the sheep were merely scavengers; they were kept to assist with general farming practice. They were a mixed lot, producing an average of about 11 lb. of wool per head and rearing about 60% of lambs.
The management adopted was not revolutionary; it merely followed the fundamentals of better feeding, heavily culling and rearing more lambs as replacements.
An initial culling of 40% reduced the breeding flock to 300 ewes - a good nucleus for future flock improvement. At the same time, 30% of ewe hoggets were culled for obvious wool and conformation faults.
To recover these losses, attention was then focused on higher lambing percentages. These were improved by flushing ewes before mating, using vasectomised rams to concentrate lambing and by feeding ewes adequately during the latter stages on pregnancy. As a result, the wool cut rose to an average of 14–15 lb per head, and the annual lambing exceeded 90%. In addition, the modified Mules operation considerably reduced flock wastage from blow-fly strike.
Besides this rehabilitation work, cereal trials were established on a limited scale in 1948. Wheat variety trials included about 20 varieties and advanced crossbreds; this work has been continued and developed further during the ensuing years. Towards the end of this period, trials with cereal seed pickles, introduced pasture plants and hormone type weedicides were also initiated. The Centre was now demonstrating the advantages of farming methods designed to build and maintain soil fertility. It has achieved stable agricultural production suited to the environment.
By 1953, a stage had been reached when more emphasis could be place on research, and its name accordingly changed to the Minnipa Research Centre."
"Until 1960, a broad rotation of wheat - oats - pasture - oats (grazing) - pasture was generally adopted with some fallowing for seed crops. This period during the late 40s and 50s developed soil fertility to a high degree and rotations were narrowed in the 60s, although seed crops were still grown on fallow. In general, the rotation adopted was a two year wheat-pasture for maximum cereal production; with some paddocks being sown to oats for sheep feed. An average of 60kg/ha superphosphate was applied a year to each paddock. Feed conservation was emphasised and included silage, hay and grain.
During the 1960s the total area cropped each year increased from 120 hectares to 400 hectares. During the period, pastures became grass dominant and plans were laid to combat this by more frequent cropping, heavier strategic grazing, and the use of new medic varieties. The 70's were a period of development of the Centre's infra structure - many buildings, fences, and water systems were improved, replaced and re-organised.
In the 80s a larger operating plant was purchased and the change was made from bags to bulk handling. The area sown each year was increased to about 600 ha. The advent of new herbicides enabled the earlier sowing of crops and methods were developed to enable paddocks to be sown after as little as 8 mm of rain. One of the methods often used for seeding during the 1980's was broadcasting followed by harrowing. Early seeding was strongly promoted by Dr. Bob Holloway (Manager 1977–2003), and had an immensely positive effect on the returns of the Eyre Peninsula farmers who adopted it during this period. In 1983, a paddock was sown in this way yielded 3.2t/ha, and in 1986, another paddock yielded 3.0t/ha. The advantages of early seeding were clearly demonstrated in 1987 when a paddock sown on May 2 yielded 2.28t/ha compared with the overall wheat average of 0.75t/ha, where most other paddocks were sown in late June.
During the early part of the 1980s, the Centre carried large numbers of sheep and cattle and in 1982, which was a severe drought, 1120 ewes were mated and 1963 sheep shorn, with a cropping are of 569 ha. This created a severe strain on all resources and over the next few years the numbers of livestock were reduced to a sustainable level. Feedlotting has been adopted as a regular practice to allow the removal of stock from medic pastures after maturity and to allow maximum retention of residue on the soil over summer.
The battle with grassy pastures has continued during the 80's although the advent of selective herbicides for the removal of grass from pasture has enabled the establishment of some excellent medic pastures. Nevertheless, the ability of grasses to dominate a paddock a few years after removal of at best 95% of the population is amazing. Other methods of grass removal have involved the use of non selective herbicides in the year prior to cropping, the spray topping technique or occasional use of herbicides to remove grass in the cropping year.
The removal of grasses has enabled crops to be sown as soon as sufficient soil water is available after April 20. Broadleaf weeds are dealt with using the wide range of herbicides now available. The most difficult broadleaf weed to deal with during the 80's has proven to be soursob (Oxalis pes-caprae) which has slowly spread to almost every paddock on the Centre, after having originated from soil around olive truncheons planted in the early years of the Centre.
The general rotation adopted is similar to that adopted in the 1960s – wheat-pasture in most paddocks, with dry sown CCN resistant oats used to booster the early feed available for sheep, and some oats for seed and feed. Fertilisers are applied only to crops, at the rate of about 5kg/ha P per year. A single paddock has been set aside for continuous cropping (N12 has been cropped continuously with one exception since 1976; over the last 5 years the paddock has been sown to wheat). Another paddock, S9, was set aside for organic farming practices in 1988.
Most paddocks now are direct drilled and very little pre-sowing cultivation is practiced. Many paddocks are sown immediately after sufficient soil water is available after April 20, with no prior cultivation. Occasionally a single cultivation is adopted before sowing for the incorporation of herbicide. Grain legumes have not proven successful - lupins appear to be poorly adapted to the area and usually produce stunted plants and low amounts of grain. Chickpeas occasionally produce successful crops in good rainfall years but again their short stature presents reaping difficulties. Pea crops have been grown successfully on the Centre but difficulties with reaping have been the major problem where stones and stumps remain. Soil erosion is a real risk with pea stubbles although this has been avoided by not grazing the stubble at all until late March, and then only for a few days with low numbers of stock.
The planting of trees was taken up in the late 1970s and the row of eucalypts along the road east of the main office was planted in 1977. A few hundred or so trees were planted each year until the late 1980s when up to 1,000 trees are planted each year, many of them propagated on the Centre.
The 1980s were marked by severe droughts in 1982 and 1988, with generally late seasonal openings.
https://www.sardi.sa.gov.au/about_us_2/facilities/minnipa_agricultural_centre (link opens in new window)
https://www.sardi.sa.gov.au/about_us_2/facilities/minnipa_agricultural_centre/history (link opens in new window)