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Stubble : Friend And Foe, Department Of Agriculture And Food, Western Australia

Journal of the Department of Agriculture, Western Australia, Series 4

Several articles in this issue of the Journal of Agriculture discuss some of the important issues of stubble management. The articles are condensed from some of the papers presented at a stubble workshop at Geraldton in 1991.

Wider Spaced Rows For Lupins, Ron Jarvis

Journal of the Department of Agriculture, Western Australia, Series 4

In this farm scale trial at Wongan Hills, a lined combine was used to seed lupins into rows spaced 380 mm apart in wheat stubble.

Results Of Stubble Research In Western Australia, Michael Perry, Ron Jarvis, Mel Mason, David Tennant

Journal of the Department of Agriculture, Western Australia, Series 4

Few farmers would question the desirability of retaining stubbles, both for control of erosion by wind and water, and to return organic matter to the soil. While the present debate is focused on the short term management of stubbles, longer term effects also need to be considered.

The Department of Agriculture has several long-running trials intended to measure long term effects.

Red Kangaroos Can Set Back Range Regeneration, Andrew Mclaughlin

Journal of the Department of Agriculture, Western Australia, Series 4

After years of severe drought, stocking rates in Western Australia s arid rangelands have been kept low since the 1970s to allow native pastures to regenerate. As well, extensive re-seeding programs have started and sheep and cattle grazing on these areas has been restricted or eliminated. However, pasture regeneration in the rangelands can only succeed when grazing by all animals - sheep, cattle, kangaroos, goo.ts, camels, brumbies and donkeys - is controlled Many more red kangaroos roam throughout Western Australia's pastoral areas today than 20 years ago. The installation of windmills and troughs to water domestic livestock has allowed kangaroo …

Stubble Retention For Control Of Wind Erosion, Dan Carter, Paul Findlater, Steve Porritt

Journal of the Department of Agriculture, Western Australia, Series 4

The surest way to control wind erosion in continuous cropping systems is to retain stubble. Over the past ten years, Western Australian research has focused on the amounts of stubble needed to prevent that erosion.

Trees And Livestock : A Productive Co-Existence, Richard Moore

Journal of the Department of Agriculture, Western Australia, Series 4

Trees, as part of farming can help to combat land degradation problems and produce a good economic return from timber at the same time. For example, there is now clear evidence that planting trees can help combat salinity by lowering water-table levels. Trees can also substantially improve overall farm productivity by providing shelter for pastures and livestock. The challenge is to find practical and economical methods of integrating trees and farming. A combination of widely-spaced trees and livestock is one promising method. This article describes the benefits of this type of agroforestry to farmers, suitable locations and how to practice …

Planting Trees To Control Salinity, Nick Schofield, Phil Scott

Journal of the Department of Agriculture, Western Australia, Series 4

Dense tree plantings covering at least 30 per cent of cleared land can lower groundwater levels by two metres or more in 10 years from the time of planting. This sizeable drop can be expected at sites receiving 700 to 800 mm of rain a year. Research by the Water Authority of Western Australia shows the most promising strategy when using trees is to put dense plantings on the discharge zone and on lower to midslopes. This strategy is successful where groundwaters contain less than 30,000 milligrams per litre total soluble salts (TSS).

This article discusses research in the 450 …

Tree Crops For Profit And Land Improvement, John Bartle

Journal of the Department of Agriculture, Western Australia, Series 4

Western Australian agriculture is deficient in good perennial species. The traditional segregation of agriculture and forestry has diverted attention from commercial wood producing trees as a potential perennial crop. Recently, scientists have made rapid progress in developing tree cropping systems suitable for extensive use in the wetter (more than 600 mm average annual rainfall) areas of the lower south-west. There is potential for a major industry based on fast-growing eucalypts for pulpwood. The foundations for this industry developed from work on agroforestry, forestry sharefarming and salinity control.

Reclaiming Sandplain Seeps Planting Trees, Richard George

Journal of the Department of Agriculture, Western Australia, Series 4

Sandplain seeps affect large areas of agricultural land in Western Australia's eastern and northern wheatbelt and in the Great Southern. These seeps are estimated to account for about 10 per cent of dryland salinity in the agricultural area. Research and field observations show that seeps may be cheaply and quickly reclaimed using various types of drains or small blocks of trees (George 1990). This article discusses results of reclamation methods associated with tree planting on sandplain seeps in the eastern wheatbelt.

Deep Tillage : Keep An Eye On Costs As Well As Yields, Amir Abadi, Andrew Bathgate

Journal of the Department of Agriculture, Western Australia, Series 4

Deep tillage overcomes compaction of sandy soils caused by movement of heavy machinery. Many experiments since 1981 have shown cereal yields improve as a result of deep tillage. However, the increased yield does not necessarily mean more profit when costs are taken into account. To determine the profitability of deep tillage farmers must consider its impact on other farm operations. A whole-farm analysis is needed to accurately determine the increase in profit resulting from deep tillage

Survey Of The Damage Caused To Trees By Goats, Steve Gherardi, Dick Mills, Tim Johnson

Journal of the Department of Agriculture, Western Australia, Series 4

The damage that goats can cause to trees is one of the major problems associated with their farming in the agricultural areas of Australia. It is also considered one of the main hindrances to the development of the goat industry. The Department of Agriculture s Goat Industry Development Unit surveyed mohair and cashmere producers to determine the prevalence of tree damage and its extent and severity; why producers believed goats damaged trees; and how producers minimised or prevented this damage.

Windbreaks Prove Their Worth, Tim Negus

Journal of the Department of Agriculture, Western Australia, Series 4

Strong winds in the south-west of Western Australia in April 1991 carted tonnes of top soil from stubbles, over-grazed pastures, and recently prepared cropping land. However, where there were windbreaks, downwind protection into the paddock was up to 10 to 20 times the height of the windbreaks. On May 1, 1991, the author inspected farm land for damage from Narrogin to the Dongolocking area, to Harrismith, up the rabbit-proof fence to West Corrigin and back to Narrogin via Kweda. He found the extent of soil erosion varied, and that some tree species planted in windbreaks gave better protection than others

Whole-Farm Planning : Success At Wilgi Creek, Kevin Shanhun

Journal of the Department of Agriculture, Western Australia, Series 4

Ian and Bev Lynch own Wilgi Creek, a 376 ha mixed farming property at West Mount Barker in the 700 mm rainfall zone. In 1983, they started a whole-farm plan to overcome the problems of declining production caused by waterlogging (their biggest problem), salinity and deterioration of the remnant native vegetation. Today, their property is an example of a successful, wholefarm land conservation plan based on agroforestry, timber production, water harvesting and improved pastures.

Revegetating Salt-Affected Land With Shrubs, Ed Barrett-Lennard, Fionnuala Frost, Steve Vlahos, Norm Richards

Journal of the Department of Agriculture, Western Australia, Series 4

The establishment of salt-tolerant shrubs such as saltbush and bluebush on salt-affected land reduces the risk of soil erosion, and can also fit into farm programmes as a profitable enterprise. Salt-tolerant shrubs can be used as forage for sheep in summer and autumn, when the availability of annual pastures is low or annual pastures are just beginning to emerge. This article describes three methods for establishing shrubs on salt-affected land and what affects shrub establishment.

Variable Quality Of Saltbush Seed Influences Establishment, Stephen Vlahos, Donald Nicholas, Clive Malcolm

Journal of the Department of Agriculture, Western Australia, Series 4

Farmers are using niche seeders to direct-seed saltbushes (Atriplex spp.) cheaply on large areas of salt affected land. While many factors influence successful establishment of these shrubs, fanners can control the quality of the seed they use. Too often, the lack of knowledge of saltbush seed quality has resulted in extremely poor establishment. The importance of seed quality is well recognized in the establishment of grain crops and pastures, but it is often overlooked when farmers buy or select seed of saltbush. If farmers know the quality of the seed they buy, they can make appropriate adjustments to the sowing …

Wildlife Corridors In The Wheatbelt, Richard Hobbs, Denis Saunders

Journal of the Department of Agriculture, Western Australia, Series 4

Native vegetation in the Western Australian wheatbelt now persists mostly in small areas that remained uncleared for various reasons. (See 'Remnant vegetation on farms is a valuable resource' on page 43.) On their own, most of these remnant areas are difficult to manage, and too small to retain viable populations of many of the birds and other animals found in the wheatbelt. These patches of vegetation can be linked by wildlife corridors, which may increase the ability of the wildlife to move about and persist in the area

Phosphorus Retention Of Sandy Horticultural Soils On The Swan Coastal Plain, Ian Mcpharlin, Neil Delroy, Bob Jeffery, Greg Dellar, Maurice Eales

Journal of the Department of Agriculture, Western Australia, Series 4

Soils can be ranked according to their phosphorus retention capacity by the phosphorus retention index (PRI). This is the ratio of phosphorus adsorbed by soil to that remaining in solution under a set of standard conditions. Although it is a laboratory measurement, the PRI seems to be a good indication of what happens in practice.

Can Kangaroos Survive In The Wheatbelt?, Graham Arnold

Journal of the Department of Agriculture, Western Australia, Series 4

One of the costs of agricultural development in Western Australia over the past 100 years has been the loss of most of the native vegetation and, consequently, massive reductions in the numbers of most of our native fauna. Thirteen mammal species are extinct and many bird and mammal species are extinct in some areas. These losses will increase as remnant native vegetation degrades under the impact of nutrients washed and blown from farmland, from the invasion by weeds and from grazing sheep.

Even kangaroos are affected. Unless the community manages remnant vegetation to minimise degradation and enhance the regeneration of …

The Extent And Cost Of Waterlogging, Don Mcfarlane, Buddy Wheaton

Journal of the Department of Agriculture, Western Australia, Series 4

Waterlogging is an underrated and not widely recognized problem in our cropping areas. Before we can tackle the problem through drainage and alternative cropping systems, we need to know its extent and how much crop yield is lost. The effect of waterlogging on pasture growth is also poorly known.

Economics Of Interceptor Drains : A Case Study, Andrew Bathgate, Ian Evans

Journal of the Department of Agriculture, Western Australia, Series 4

This case study determines the most likely rate of return to capital invested in constructing seepage interceptor drains to reduce the effect of waterlogging on crop and pasture yields. The analysis of a farm in the Denbarker region, west of Albany, determined what increases were needed in pasture growth to justify the cost of constructing drains across four adjacent paddocks. The benefits of changing rotations to include lupins were also determined, as growing lupins was unprofitable before the construction of drains.

Integrated Control Of Soil Insect Pests Of Potatoes, Stewart Learmonth, John Matthiesson

Journal of the Department of Agriculture, Western Australia, Series 4

One of the more difficult aspects of growing potatoes in Western Australia is controlling soil insect pests. These pests have become more troublesome because the highly effective and persistent organochlorine insecticides previously used to control the main soil pests, African black beetle and whitefringed weevil, were deregistered for agricultural use in 1987. Entomologists from the Department of Agriculture and CSIRO in Western Australia are collaborating to develop new management strategies for these pests that rely less on the use of chemical insecticides

Flower : Predicting Flowering Times Of Cereal Crops, G A B Elliott, Stephen Loss

Journal of the Department of Agriculture, Western Australia, Series 4

FLOWER is a computer program which predicts the flowering date of a given wheat or barley variety at a specified location and sowing date. Department of Agriculture agronomists, breeders and advisers are using the program to provide useful information on how the development of cereals responds to different environments across Western Australia's cereal growing areas.

The Effect On Farm Profit Of Conserving Stubble To Prevent Wind Erosion, A D. Bathgate

Journal of the Department of Agriculture, Western Australia, Series 4

Over-grazing of stubbles is a major cause of winf erosion on WesternAustralian farms. Stubble contributes to the 'roughness' of the paddock; as the roughness is reduced, the risk of winf erosion is increased.

The risk of lupinosis in sheep has previously reduced the likelihood of lupin stubble being over grazed, but the development of Gungurru, a phomopsis-resistent variety of lupin, has increased the potential for over-grazing and hence the probability of wind erosion.

This article describes the economic benefit (or cost) of conserving stubble at the conservation standards.

Frost Injury To Wheat, S P. Loss

Journal of the Department of Agriculture, Western Australia, Series 4

Frost injury has not been a major concern to the Western Australian wheat industry despite causing spectacular but irregular crop losses on some farms.

The development of suitable herbicides, direct drilling technology and the adoption of early flowering varieties in the late 1970s and early 1980s led to wheat crops being sown and flowering earlier than previously. This resulted in an increase in the incidence of frost damage.

Research into frost indicates that most wheat producers face low to moderate risks of yield loss caused by frost. However, individual farms in particular years can suffer devestating widespread losses. Grost injury …

Finishing Kimberley Cattle In The South-West, Brian L. Mcintyre, Bill Ryan, Neville Macintyre

Journal of the Department of Agriculture, Western Australia, Series 4

The idea of integrating the Kimberley cattle industry with that in the south-west of Western Australia is no new, but until recently it had not been critically evaluated.

Over the past eight years the Department of Agriculture's Beef Cattle Branch has been assessing the performance of Kimberley cattle transported south for finishing in the agricultural areas.

This research has show that Kimberley weaners can be finished in the south, and that under the present (December 1988) economic conditions it is more profitable than running breeding cattle in the south-west and comparable with fattening store steers.

Breeding Field Peas : Screening Pea Lines, G H. Walton

Journal of the Department of Agriculture, Western Australia, Series 4

The early use of field peas in Western Australia was as a green manure crop or to feed stock be grazing the mature crop. Varieties which produced a large bulk of green material were sown. There was no control over insects or diseases.

In 1985, the Feseral Government recognised that to realize the potential of grain legumes grown throughout Australia, more research was needed.

One of the Grain Legume Research Council's (GLRC) priorities is species evaluation and variety improvement.

Since 1983, the Western Australian Department of Agriculture has screened advanced crossbred lines from the South Australian breeding programme for its …

Planning For Horticultural Expansion On The Swan Coastal Plain, P Coghlan, Geoff Moore, Jim Dixon

Journal of the Department of Agriculture, Western Australia, Series 4

Horticulture is an intensive, high value form of agriculture highly dependant on the availability of good water supplies for the year-round production of fresh produce. Production increase in Western Australia and the encouragement and development of export markets has caused rapid expansion if the industry in recent years.

Expansion is expected to continue, placing severe pressure on available water supplies and suitable land close to markets. At present' 90 per cent of the Stase's horticultural land is on the Swan Coastal Plain and minor selected hills areas around Perth.

Irrigation And Fertilizer Management For Horticultural Crops On The Swan Coastal Plain, I R. Mcpharlin, Greg Luke

Journal of the Department of Agriculture, Western Australia, Series 4

The Swan Coastal Plain is an important area for the production of vegetables, flowers and fruits in Western Australia. The yellow Cottesloe, Karrakatta and the white-grey Bassendean Sands upon which most of this production is based are infertile in their natural state and require large inputs of fertilizer for succesful production of horticultural crops.

Improved irrigation and fertilizer management will be needed to reduce nutrient leaching from horticultural crops on the coastal plain. This will probably involve applying fertilizer and water more frequently, but in smaller quantaties thaan currently practiced. The result should more closely match water and fertilizer supply …

Improved Fertilizing Practices On The Peel-Harvey Catchment, P T. Arkell

Journal of the Department of Agriculture, Western Australia, Series 4

Broad-acre farmers in the Peel-Harvey catchment have met a challange and achieved a great deal since the fertilizer extension programme started in 1983.

The main objective of the extension programme has been to ensure that every year three-quarters of the farmers make economically and technically sound fertilizer decisions, thus causing a minimum amount of phosphorus to enter the waterways of the Peel-Harvey estuarine system.

Intensive Animal Industries In The Peel-Harvey Catchment, R W. Payne

Journal of the Department of Agriculture, Western Australia, Series 4

The Swan coastal plain to the north and south of Perth is attractive for the intensive production of pigs and poultry for several reasons. It is close to markets, feed manufacturers and labour; has a less extreme climate than inland areas; and is underlain by a large reserve of high quality groundwater.

Because these are all intensive operations, large quantaties of nutrient-rich waste are produced over a very small area. They can severely damage ground and surface waters unless steps are taken to control the wastes which they produce.

This article oulines both the nature of intensive aniamal industries in …