• At the Howlong site, applied nitrogen gave a yield and dry matter (DM) response, however there was no sulphur response.
• The Yarrawonga site showed a clear response to applied sulphur (S) and nitrogen (N), despite high soil sulphur levels. This suggests canola roots may not be effectively exploring the soil profile to access soil sulphur.
• The Yarrawonga site had an optimum sulphur application rate of 20kg S/ha, with yield penalties measured with sulphur rates above and below this optimal rate.
• The dry finish to the season caused significant challenges during 2017. This trial will be repeated at two sites during 2018 to understand how variable the responses to sulphur are likely to be during different seasonal conditions.

• At the Howlong site, applied nitrogen gave a yield and dry matter (DM) response, however there was no sulphur response.
• The Yarrawonga site showed a clear response to applied sulphur (S) and nitrogen (N), despite high soil sulphur levels. This suggests canola roots may not be effectively exploring the soil profile to access soil sulphur.
• The Yarrawonga site had an optimum sulphur application rate of 20kg S/ha, with yield penalties measured with sulphur rates above and below this optimal rate.
• The dry finish to the season caused significant challenges during 2017. This trial will be repeated at two sites during 2018 to understand how variable the responses to sulphur are likely to be during different seasonal conditions.

• Crop productivity on infertile sandy soils can be greatly improved by incorporating organic matter deep into the soil (>30 cm).
• In some cases, crop yields are further boosted with the incorporation of clay and/or fertiliser to depth.
• Two years of recent research show that the best soil modification treatments can increase crop yields by 70 to 200 %, even in challenging seasons.
• Treatments that address multiple constraints in these soils provide greater benefit than those addressing individual issues.
• Crop yields are reduced when clay is poorly incorporated into the soil.

5 Experiments started in 1980's.

3 sources of Cu (sulfate (25%); oxychloride (52%)  & chelate (EDTA 15% Cu) at 7 levels of Cu

Applied at 2 growth stages of wheat grown at 5 sites

1 kg Cu/ha rsuilted in maximum yield of 2.5 t/ha (summarised over 5 experiemnts in each particular year.

1-2kg of Cu sulfate required for maximum yield on severely deficient soil (.5 tha nil Cu ; 2.5 t/ha adequate Cu)

Little foliage damage if sprayed under cool, cloudy conditions. Warm sunny conditions increased leaf damage and decreased response to foliar sprays.

Chelate Cu always resukted in the highest yield per quantity of Cu while oxychloride always rsulted in the lowest grain yield per quantity of Cu .For example 100 g Cu/ha of chelate , 200 g as sulfate and 4000g oxychloride Cu for maximumgrain yield.

Sprays at 6th leaf were higher than late boot.

Cool condition for leaf absorption.

Results replicated over several season and soil types.

5 Experiments started in 1980's reported in 1985-86.

Sources of Zn (sulfate (22%);  & chelate (EDTA 15% Zn) at 5-7 levels of Zn

Applied at 2 growth stages [4th leaf; mid-tillering] of wheat grown at 5 sites.

Wheat sprayed at 4th leaf yielded higher [ about 0.5 t/ha higher) than delaying until mid-tillering under severely Zn deficient plants.

0.45 kg Zn/ha for both times of spraying resuilted in maximum yield of 1.5 -2.5 t/ha (summarised over 5 experiemnts) in each particular year. About 50 -60% grain yield increases.

Zn chelate was more effective at the  4the leaf stage. About 200 g Zn/ha for maximum grain yield for chelate while 450 for the sulfate source.

At mid-tillering about 250-300 g Zn/ha required for maximum yield for both chelate and sulfate 

 Recommendation : 1 kg of Zn sulfate required for maximum yield on severely deficient soil; spray on onset of symptoms.

Little foliage damage if sprayed under cool, cloudy conditions. Warm sunny conditions increased leaf damage and decreased response to foliar sprays.

Sprays at 4th leaf were higher yielding than the mid-tillering stage.

Cool condition for leaf absorption.

Results replicated over several season and soil types.

• Drying soil conditions at the time of sowing, caused a poor initial germination of seedlings.
• Grain yield tended to increase as the rate of phosphorus fertiliser applied increased.
• The liquid NP source performed no better or worse than the solid NP source.

• The early crop vigour results in this trial demonstrates the need to apply fresh phosphorus to crops at seeding to ensure good plant shoot and root growth during the early stages of crop growth.
• There was no difference observed between potassium drilled with the seed or topdressed immediately after sowing.  Good rainfall conditions early in the season may have rapidly moved the topdressed potassium into the root zone of the crop therefore overcoming any differences due to placement.  Subsoil testing for potassium may be important to determine the size of the soil potassium pool.

• Movement of water towards P fertiliser granules occurs and in calcareous soils this causes P to form a solid precipitate with calcium ions and prevents P moving away from where it is applied and reduces likely availability.
• Manganese from fluid fertilisers moves further away from point of application compared to a granular source of Mn and was potentially more available.
• Movement of zinc away from point of application was restricted regardless of the source and in both soils but fixation of zinc was less when the sources was fluid rather than granular.

• Seeding depth uniformity is influenced by both seed placement quality within the furrow and the consistency of added soil cover
• Many machinery design and operating parameters affect the uniformity of seeding depth across a paddock
• Deep sowing (eg. beyond 50-6omm) can significantly affect crop emergence and final grain yield
• Many paddock situations can soon suffer a 5-10% yield loss as a result of inadequate seeding depth, with more extreme situations suggesting possible yield penalties of 15-20% or more.

• Trace element investigations have revealed that pastures previously unresponsive to improvement can now be expected to respond after the application of molybdenum.
• Molybdenum should not be applied in excess.
• On coastal soils of southern Victoria and the far west copper is the most important trace element deficiency.
• In east Gippsland both copper and molybdenum deficiency occur together.
• In poorer dairying districts there is no response to molybdenum until potash is applied.

Pasture cropping is an option for KI producers wishing to maximise grazing/cropping options.
The key principles are:

• Graze the paddocks down to 75-100 mm with livestock, or apply herbicides. Aim to suppress (but not kill) the pastures either with the judicious use of herbicides to burn the perennials or through appropriate grazing to take out the annual weeds.
• Zero till with a tyne or disc. Minimise soil disturbance as it kills pastures and encourages weeds. The aim is to open a slot and loosen the soil to create sufficient tilth for germination of the seed crop.

• The MLA trials demonstrated that early summer seeding (January) of Serradella pod was a viable option. The summer sowing of Serradella pod has outperformed the twin sowing methods in the two trials conducted by SCF growers
• The current district practice of dry seeding pasture seed in Autumn on sandplain soils has severe limitations compared to summer pod sowing or seeding when soil is moist after full seasonal break. This was confirmed in the 2014 season in the MLA trial where the second time of sowing (into moist soil) outperformed the first time of sowing in total legume biomass production and this advantage has carried right through to seed set in Year 3 (in M1 trial Santorini and Margurita plots).
• The performance of a precision seeder for sowing Serradella in a 2015 trial demonstrated that modifications of conventional seeding systems could improve plant establishment efficiency by more that 35%.
• The hard seeded Serradellas are performing well in specific treatments in the MLA trials even on the lower fertility, acidic and non-wetting sandplain soils. Mixed maturity Serradellas like cv Margurita lose significant pod set with spraytopping ryegrass compared to Cadiz or Santorini.

• Further examination is necessary to determine to what degree winter cleaning in the final pasture year will improve the nitrogen status of the soil.
• These conclusions will need to be verified over several more seasons before reliable relationships can be confirmed.

• There was good correlation between the visual cuts and satellite data early in the season, but during the spring results diverged.
• Further work is required to fine-tune the satellite data for KI, including soil characteristics and more accurate rainfall data.
• Pastures from Space is a useful tool for landholders to further fine-tune their grazing operations.

• All plants performed poorly on the shallow gravel with moisture stress becoming evident.
• Weed control was poor with wild radish competing strongly with the perennials for moisture.
• The trial will continue for the next 2 years with more results becoming available during this time, including palability, feed value and persistence.

• Atriplex nummularia (Old man saltbush, 79.2% survival), Atriplex rhagodioides (Silver saltbush, 77.1% survival), and Rhagodia parabolica (Mealy saltbush, 76% survival) are the species with the highest survival rates.
• Weed control was poor with wild radish competing strongly with the perennials for moisture.
• The trial will continue next year with more results becoming available during this time, including palability, feed value and persistence.

• Demonstration sites are monitored annually for pasture and surface cover, biomass production and frequency of perennials.
• Soil sampling will occur again in late 2014/15 to determine any change in soil organic stocks as a result of the implementation of a change in management practice.

• Establishment of perennial pastures is relatively expensive and represents a high risk activity during years with very low spring rainfall. • Ideally Lucerne and pasture grasses should be established by sowing early in paddocks with low weed populations, such as may occur after several years of a well managed cropping program.
• Press wheels will improve establishment in some soil types.Establishment of perennial pastures is relatively expensive and represents a high risk activity during years with very low spring rainfall.
• Ideally Lucerne and pasture grasses should be established by sowing early in paddocks with low weed populations, such as may occur after several years of a well managed cropping program.
• Press wheels will improve establishment in some soil types.

• Crusher TT canola yielded between 2.24–2.79 t/ha with 232mm of growing season rainfall (Apr–Oct) and an estimated 118mm of stored available soil moisture (total 350mm).
• All plant populations were high (150–200 plants/m2) due to an error in calibration, however results produced were similar to previous years, with no significant difference in yield between the narrowest (22.5cm — 2.67t/ha) and widest (37.5cm — 2.75t/ha) row spacings.
• The 30cm spacing yielded significantly lower than both the 22.5cm and the 37.5cm spacings in this trial. 

• Canola following two years of wheat yielded 2.08t/ha despite establishing 50% fewer plants than canola grown during 2009, which yielded 1.59t/ha. The higher yield achieved during 2011 was attributed to more stored soil moisture at sowing. 
• The higher biomass produced with the narrower row spacing (22.5cm) did not translate into higher grain yield with the same yield achieved across the narrowest (22.5cm) and widest (37.5cm) row spacings.
• About 102-122kg nitrogen/ha was removed in aboveground biomass (straw and grain). There was no statistical difference in nitrogen off-take between the 22.5cm and 37.5cm row spacings.  

• Starter application of P was important in maximising yields at GS30.
• Grain yield responses (< 90 percent relative yield) to P were obtained for 35 percent of the paddocks surveyed.
• DGT accurately predicted wheat responses to P accounting for 64 percent and 79 percent of the variation in early dry matter and grain respectively.
• Colwell P could only explain 36 percent of the variation in early dry matter and no significant relationship could be obtained with grain.
• Colwell P plus the Phosphorus Buffering Index (PBI) correctly predicted wheat response in 60 percent of the sites.

• In the 2012 wheat after canola trial, moving from a narrow row spacing (22.5cm) to a 30cm spacing reduced yield by 9%.  Moving from 22.5cm to the widest (37.5cm) row spacing reduced yield by 11%.
• In a season where yields averaged about 3t/ ha overall (based on a GSR of 196mm plus 85mm stored soil moisture), increasing row spacing beyond 22.5cm significantly reduced yield.
• During 2009, in the same rotation position on the same trial site, there was no difference in yield between the 22.5cm and 30cm row spacings (based on 2.5t/ha average yields), although the 37.5cm row spacing still yielded significantly less. 

• Trial sown at Lameroo on a zinc deficient soil, very dry season.
• Untreated crop was severely zinc deficient.
• Zinc seed dressings (Teprosyn and Broadacre products) were effective at alleviating zinc deficiency but not as effective as the dressings plus mid season foliar spray.
• The soil sprays were not very effective, even at double the recommended rate, perhaps because the soil was so dry.
• Although laboratory experiments had shown that MAP was more effective than DAP fertiliser in terms of zinc availability, no differences were observed in the field experiment.

Agronomists and farmers throughout the Glenthompson region appreciate the presence of potassium deficinancy, however little has been done to understand the spatial distribution across the landscape. This demonstration trial has utilised a range of spatial technologies, strategic soil sampling and local knowledge to determine opportunites for variable rate potash.

SANTFA’s 2010 field trial in calcareous cropping country near Streaky Bay demonstrated the strongest evidence  yet for biochar’s capacity to influence fertiliser efficacy and crop yield in SA’s cropping system.

The biochar data collected from the 2010 trials is analogous in many ways to what we would expect from spreading clay on non-wetting sands: little response at very low rates, an excellent response at the appropriate rate and a potential problem if the soil is over-clayed or the wrong clay (such as a limey clay) is applied. 

A significatn yield increase was observed on the Barber site from the application of 10kg P/ha compared with the zero and 5kg P/ha treatments.

• Different crop types displayed varying phosphorus (P) use efficiencies (soil and fertiliser demand) under P deficient conditions.
• Crop types that have previously shown to be P efficient did not display the same traits in neutral to slightly alkaline soils.
• Soil testing can have significant economic benefits if the right test is used.

• Phosphorus is an essential nutrient for plant development which cannot be effectively applied post sowing. Because of this it is imperative that decisions on its application are made now.
• P should be applied at rates necessary achieve the yields being targeted in a given paddock for a given year.
• Information to assist you in determining how much P is in your soil includes fertiliser history, removal through production previous yields, soil tests and paddock history.

• In this district and in reference to the soils that are low in exchangeable aluminium – that is to say the soils where barley, canola and lucerne can realise their water limited yield potentials without the need for the application of lime, that negligible quantities of phosphorus are lost to the soil pool. The
• It is stressed that after 2007 you should apply at least the usual recommended phosphate rate to your 2008 wheat crops to achieve their water-limited yield potential

The objective of this GRDC / SPAA funded project is to increase the level of adoption of PA 'beyond guidance' by broadacre farmers. The project specifically aims to increase the level of adoption of variable rate (VR) by growers in the project to 30% by 2013.This goal will be achieved by demonstrating how to use PA tools to growers at a regional level and by increasing the skills of growers and industry in PA to a level where they can then use PA tools in their farming systems to achieve economic, environmental and social benefits. The grower mentioned the importance of correctly identifying the GPS coordinate locations to get reliable soil type information. Yield maps provided showing areas of the paddock with high and low potential assisted this process. Soil analysis verified the trends produced by the yield map.

• Soil test results indicated that the P levels on the trial site were not particularly low.
• Despite the dry conditions in September, grain yields ranged from 1.59 to 2.16 t/ha.
• Results demonstrate that application of P up to 40 kg P/ha can increase field pea yields. To maximise grain yield, P rates above 40 kg/ha may be needed.

• A pot study using 32 virgin soils from south-eastern Australia (Vic - Qld).
• Subclover grown in pots in the glasshouse and nutrient relations examined.
• Sulphur deficiency occurred almost as frequently as phosphorus deficiency.
• 75% of the soils were deficient in both phosphorus and sulphur, 31% were deficient in all three elements.
• Molybdenum responses were obtained only after the other deficiencies had been corrected.
• A deficiency in one of the elements is no indication of deficiency or sufficiency of either of the other two.
• Responses to phosphorus were less on the black earths than on the red or yellow podzolic soils; those on the red earths were intermediate.
• The intensity of sulphur deficiency increased, and the intensity of molybdenum deficiency decreased, with increasing soil pH.

• The production and farm management lessons learned during the project will be made available to the KI farming community and wider South Australia through a range of information events, including field days, offered during the project and at the conclusion of the programme.

• During 1997 make the most of the technology and services available.
• Soil testing prior to sowing.
• Monitoring your crops with sap nitrate testing, NIR analysis, plant tissue and grain tissue testing during the season will enable you to make informed decisions and to capitalise on the opportunities presented.

Previous trials and demonstrations have highlighted zinc deficiencies in both cereals and pulses, which could provide farmers substantial profits over the cost of zinc. A trial conducted on wheat at Sea Lake in 2000, on a highly responsive soil type with a poor zinc history clearly defined responses to zinc and demonstrated that responses to phosphorus or nitrogen cannot be achieved if zinc is deficient. This trial also endorsed the conclusions of trials conducted in 1999 that adequate zinc enriched granular fertiliser should be regularly applied

• This project has had a large impact on Albany and Esperance growers.
• The underrepresented soil types are now predominantly covered making the Yield Prophet project more relevant to the area.
• Growers can access the information in the paddock on smart phones and tablets.
• This enables them to make better informed decisions when it comes to soil inputs and management.

• This demonstration suggests that there is a trend towards higher yields as a result of ploughing stubbles.
• The cost of ploughing stubbles is relatively low and it may be an effective way to increase soil organic matter.

• Plant numbers were variable and it is difficult to draw any conclusion from the final grain yields.
• The untreated strip yielded 1.8t/Ha. Both the PAM treatments were assessed as 1.9t/Ha, and the Irrigator soil wetter yield was 2.0t/Ha.
• This was what the remainder of the paddock yielded, and it was treated with Irrigator.

• Biodegradable polymer films retain soil moisture and increase soil temperature.
• Polymers allow crops to be grown out of season and expand the planting window.
• Sorghum and millet successfully germinated under the film failed to germinate in the absence of the film.

• Preliminary results have shown that post sowing use of some pre-emergence herbicides can improve control of late emerging ryegrass and could be beneficial as a late salvage exercise where ryegrass has escaped earlier control.
• Although no damage to the wheat crop was observed, these treatments present a higher risk to crop safety, depending on soil type and rainfall after application.
• Post sowing use of these herbicides is currently off label & requires further investigation before registration can be granted.

Barley yields exceeded 5 t/ha with strong responses to lime and potassium fertiliser.

The 1.0 t/ha response to potassium (K) was not as strong as in the previous two wheat crops (1.4 t/ha in 2013 and 2.4 t/ha in 2014). This was probably partly due to better control of ryegrass in plots without K fertiliser compared to previous years.

The response to lime applied in 2011 and 2014 was also 1.0 t/ha. This followed a 0.35 t/ha response in 2014 wheat. Like 2014, lime did not affect response to K.

Compared to topdressing potash, banding K increased early crop vigour, but 140 kg/ha K-Till Extra (15K) did not supply enough K to satisfy demand of the high yield potential.

This trial has highlighted the importance of maintaining K inputs (if required) when undertaking liming programs.

Ongoing responses to lime are likely to increase future demand for K because soil reserves will be depleted at an increasing rate.

Significant yield responses were observed indicating that lentisl can respond to K & S application during the growing season where soil nureition levels are depleted

Significant yield responses were observed indicating that lentisl can respond to K & S application during the growing season where soil nureition levels are depleted

• Mace wheat responded positively to K.
• Source of K (SOP or MOP product) and timing had minimal impact on growth or yield response.
• Drilled MOP at 100 kg/ha produced the greatest yield and returns but evidence that drilled K is better overall than topdressed applications was not conclusive.
• SummitQ soil test modelling gave an accurate prediction of optimal K fertilizer rate.
• Grain quality was characterized by low hectolitre weights, but increasing K application improved both hectolitre and screenings quality aspects.

• Sandplain soil with Colwell K analysis lower than 30 mg/kg is highly likely to be responsive to K.
• Potassium applied at 13-17 kg/ha in the compound NPK+traces fertiliser, Vigour, banded below the seed improved yields compared to NP+traces compound alone, and yields were further enhanced by applying additional 12.5 kg/ha K as MOP.
• Optimised returns will depend fertiliser and grain prices at the time. In the present trial, the greatest increase in returns were seen with Vigour 140 kg/ha at seeding plus 25 kg/ha MOP applied PSPE.

• Growth of lupins receiving chelated iron was greater than those receiving iron sulphate when grown on an alkaline soil (pH 8.7 H2O).

In our demonstration the higher fertiliser (DAP) rates produced higher yields, slightly higher protein and also slightly higher screenings when compared to the lower rate of DAP, as you would expect. The PR70 did not have any influence on yield at the lower rate of DAP, however at the higher rate of DAP the PR70 treated plot yielded 400 kg/ha less than the untreated plot. Therefore our trial demonstrates that PR70 did not produce significantly beneficial results in our area this year. More extensive replicated trial work is now
needed in our soil type to confirm the potential benefits of PR70.

Low input of continuous wheat is returning the highest gross margin in this scenario.

• Higher rainfall in 2015 allowed the crop to capitalise on extra nutrient availability with the top three treatments (canola, wheat and field pea) under a high input rotation.
• Low input on continuous wheat rotation is returning the highest gross margin in this scenario.

• Seasonal conditions reduced the potential impacts of the pre-emergent herbicides evaluated in this trial with sowing taking place under dry conditions. The top 5 cm was dry with little follow up moisture although there was enough to get the crop out of the ground. The effects of pre-emergent herbicides are generally more pronounced under very moist conditions particularly under intense heavy rain events at seeding or when the top soil is saturated for an extended period at plant establishment.
• In this trial neither yield or weed density were significantly different between the herbicide treatments.
• Weed plant densities were extremely variable within each treatment so caution should be taken when comparing grass weed efficacy in this trial.

• Continuous cropping is not an effective way to manage herbicide resistant annual ryegrass over the long term in the high rainfall zone.
• The increase in weed numbers over time can be slowed by adopting an intensive and high cost herbicide strategy, but not enough to reduce soil weed seed bank.
• Increasing annual ryegrass density by 100 seed heads per square meter was associated with a 150 kg/ha decrease in grain yield. 

• Dry pre-furrowing of sandy loam pasture at Pindar in 2003 resulted in a yield benefit estimated at $26.5/ha.
• Grain quality was not changed by pre-furrowing in this trial.

• Variable rate nitrogen management has great potential; particularly in the higher rainfall areas of the region with good responses being received in years where rainfall hasn’t been limiting.
• EM38 technology is useful in detecting depth to limestone; the benefits of this however will depend on if the yield is being constrained by rock or not (and in a lot of cases this isn’t occurring)
• In most cases, NDVI biomass readings have been highly correlated with yield.

• Knowing the amount of moisture that is available in the soil profile is invaluable when making nitrogen management decisions.
• Previous crop history (particularly hat of pulses) can have a very large impact on the levels of nitrogen required in following seasons. 

The data received from the 2007 trial year proved similar results to 2006. Although we received an extra 50mm more growing season rainfall than 2006, it was still 50mm short of the Corrigin average rainfall. With yields over 3t/ha, no-one can complain though, especially with barley prices around $480/t cash, at harvest in 2007. In terms of the trials’ aim – to find which stubble treatment better suits downhill tramlinning, the jury is still out as for the two years that the trial was run; 2006 & 2007, with limited rainfall we can only draw conclusions on the results that have been found; and for both years it was found that the burnt stubbles had higher yields over all. The burnt plots [having barer ground to seed into] collected more runoff than the other treatments in 2007. Removing the stubble can allow for light falls of rain to be more useful for a crop in such years, hence the better yield whereas having high levels of stubble in such cases can often intercept this moisture making it not available to the crop; rainfall that ponded on the stubbles evaporated before the plant could acess it [Jeff Russell pers.comm]. Subsoil moisture could have played a part in the earlier establishment of the burnt stubbles too as these plots would have got away sooner having no surface restrictions [stubble or organic matter] and therefore these plots would have had a chance to tap into the summer rainfall earlier than the other treatments [Glen Reithmuller pers.comm]. According to Dan Carter [DAFWA], burning stubbles removes valuable nitrogen, soil carbon and other nutrients and leaves the ground vulnerable to damage from wind erosion. In most cases, retaining stubbles will contribute to long-term soil fertility, through both preservation of nutrients and better moisture-holding capacity.

 

In saying this however, we found in 2007 [as we did in 2006] that the burnt [bare] stubble treatments yielded higher than any of the other stubble treatments as seen in trials. To compare against the control treatment, which has the least runoff, we use the 5%LSD = 2.14*3.94 = 8.4, which suggests that the burnt/bare and raked are significantly higher than the control since the difference between the means is higher than the LSD.

 

Key achievements were getting the trial in the ground, harvesting and collection of results. Also successful application for 2nd & 3rd years of funding Project 053042 – Precision Agriculture Systems – Impact on zone management, soil health and surface water management (Years 2 & 3).

Key findings from the trial in 2006 were that the most run off was collected from burnt stubble tramline which suggests that bare ground with tracks, can potentially aid the channelling of water more than with stubbles where water can ‘dam’ with the interference of stubble and foreign matter. As this was the first year of the trial at Corrigin it raised many more questions which will hopefully be answered in the next two years.

Late notification of project approval combined with difficulty in employing a suitable coordinator resulted in the project starting 6 months late (February 2006).

Farmer with tramlining capability easily identified.

Paul Blackwell’s (DAFWA) assistance proved beneficial, were able to combine two trial sites into one paddock to better utilise the farmers controlled traffic system. Minor issue occurred when fire from burning chaff heap destroyed original stubble trial site. New site established.

The biggest issue for the trial in 2006 was lack of heavy rainfall events, while a crop was taken off, there were very few rainfall events greater than 10mm.

Several issues occurred with the design, construction and collection of water from the water traps. After consultation with Paul Blackwell on trap design and a visit to his Pindar site (Liebe project) to visually assess the traps, we had a better understanding of how to construct the Corrigin traps. To bury 20 chemical containers into hard soil it was decided to hire local contractor to use his backhoe/digger to dig them out.

Collection of water from the water traps was a major issue too. A range of equipment and methods was trialled and found to be inadequate. After consultation with the local businesses in town, a powerful suction pump that could be screwed to a battery pack for power and ease of moving was order. The pump proved to be the right combination for the job required. A further issue arose over the 2006 trial year with water traps chemical drums becoming

slimy and animals getting trapped resulting in  blocking and clogging of the pump. To overcome this problem in 2007 we decided to a) place gauze over the hole from the trap to the pipe leading to the drum, so large matter cannot enter the drum. This has worked well so far, however it has restricted some trap’s water from entering the pipe. We are currently working on rectifying this problem. and b) a second filter was put on the water pump so now it has a main filter and a hose filter to sort though the ‘gunk’ before allowing it to enter the water pump.

 

Using precision agriculture (PA) to apply variable rate of fertilise is an easy way to test new idea on farm. Precision agriculture can be used to apply different rates of fertiliser to different areas of a paddock. Wheat responded to applied phophorus, even though soil tests indicated it had a high level of Colwell P (56mg/ka).

• Precision soil mapping for pH and nutrients can result in significant cost savings for producers.

• Mapping soil pH has greatest value if the paddocks are into their second or third rotation of lime.

• Consider including sulphur in the testing if mapping phosphorus.

• Establish several sites across the farm to monitor the ongoing pH, P and S status.

The important message from these trials is that any post seeding treatment is better than none at all.

Phosphorus is an essential nutrient for crop growth. Insufficient plant-available P, ultimately results in reduced yield. 

Crops, particularly cereals require a high amount of P for crop production, and P can often be depleted over time if optimal rates are not applied. Given P is an immobile nutrient historical application rates can bank P within the soil profile. 

Variable rates of starter fert were applied over a 4 year period, to assess the cumulative yield effect and P balance, to determine an optimal rate for crop production.

The control rate of 100kg/ha of MAPSZC:MOP (15.8kg/ha P), produced identical cumulative yields across the time span of the project to the 140kg/ha luxury rate. 

The 80kg/ha application provided sufficient P levels to maintain the phosphorus balance for cumulative yields achieved since 2017. However lower P rates will consume stored soil P reserves. 

• Previous BCG results indicated that higher plant densities achieved by increasing seeding rates provided many benefits including stable or increased yields (never a yield penalty), reduced screenings, increased access to moisture, nutrient and light and better competition against weed populations.
• The results of this trial support the findings of previous BCG research.
• For many growers seed of their preferred variety may be in relatively low supply following the 2002 drought but it will be important to maintain or increase current seeding rates in 2003.

• From soil tests we knew that P was going to be the limiting factor.
• This trial shows that there is no substitue for keeping your P rates up. For example a ~$90/ha investment achieved a return of $483/ha.
• It also show the importance of soil testing.
• Plant analysis did not show any improvement in P uptake from either product enhancer and neither of these'enhancers' improved crop yeilds.

Two significant weather events that had an important influence over the results in this project, in 2016, frost and 2017, summer rain. In 2016, there were multiple severe frost events during the critical, flowering stage of the growing season. Oats being a relatively frost tolerant species proved to be the best performing species for yield and gross returns in 2016. The broadleaf crops, both legumes and canola were severely impacted by frost.

For barley in 2016 the accumulated gross returns for two years was higher in rotation, fallow 2015; barley 2016 when compared with wheat 2015 barley 2016. This supports previous work by CFIG that including fallow in the rotation can increase gross returns over a two year period.

In season 2017 frost damage was minor when compared to 2016. Season 2017 was dominated by heavy summer rainfall and a very dry start to winter. The fallow plots were impacted by the summer rain due to lack of soil cover. The loamy, morrell soil set hard at the surface as a result of the heavy summer rain which severely impacted penetration of the seeding equipment and subsequently, crop establishment was poor. The very dry start to the season likely exacerbated the poor establishment on the fallow plots.

Oats performed well again in 2017 in terms of yield but barley produced higher gross returns. Chickpeas and lentils were the best performing of the broadleaf crops in 2017.

When the gross returns in 2017 were compared by rotation (2015-2017), it is interesting to note that 2017 cereals grown in rotation with legumes in 2016 generally performed well.

The gross returns for every rotation tested in the trial were compared on an accumulative return over 3 years (2015-2017) and the rotation with the highest accumulative return was year 1; wheat year 2; chickpeas and year 3; barley. This demonstrates the value of a legume in a rotation which contributed to the highest yielding plot, which was barley in 2017.

The top two highest total gross return rotations over three years had a legume crop in one year of the rotation. The third highest return rotation had a fallow phase which confirms fallow as a rotation option. In the top 10 highest returning rotations, 4 had fallow in one year of the rotation.

• Crops can be established and grown in 6.6 t/ha of retained stubble in the HRZ without compromising establishment
• Stubble retention in the HRZ requires careful systems based planning and attention to detail
• Seasonal conditions will strongly influence outcomes of stubble retention through factors such as pest pressure and conserving soil moisture
• Burning may not be an option in the near future because of unacceptable risks of litigation 

• The standard treatment in this trial, namely Sencor (metribuzin) 750WG plus TriflurX, provided no more that weak suppression of brome allowing substantial seed set.
• The trial demonstrates a new option for brome control in barley crops now available to growers, namely growing Scope barley and using Clearfield herbicides such as Intervix or Midas. Both products provided excellent to absolute control of brome, as well as silver grass.
• The trial also demonstrates that while the pre-emergence treatments alone provide only modest control of brome, their use in combination with Clearfield herbicides has the potential to improve the overall Clearfield performance. Their use is recommended for resistance management purposes and as a means of securing yield by reducing early weed competition.
• Achieving absolute control of brome grass by treatments that pay for themselves and deliver a surplus to users (of $45 – $150 per hectare) should make most Clearfield treatments highly attractive. Atlantis, Crusader and Monza each only provided strong suppression that in the long run cannot be expected to overcome brome. Regardless of their return on investment, they failed to deliver satisfactory brome control (i.e.. >90% so that the seed bank is not dramatically reduced) and are useful only in terms of managing brome within the current crop at best.
•  

• The use of pulses in the southern regions show some potential- further trial work needs to be done to examine this fit.
• Follow up Sub soil and Deep N tests need to show +/- effect of N in system
• Pulses could be economically viable as a crop, disease and weed break.

The potential advantages of growing pulse crops are well recognised, such as: increasing soil nitrogen,
breaking disease cycles for cereal crops, providing a high nitrogen feed grain and being a cash crop in their
own right. Field peas are well suited to the Central West and other pulses are useful, depending on pH,
drainage and weed control.

• Chickpeas were consistently amongst the highest yielding pulses at this site across all soil types and EM39 ranges.
• They produced the highest gross margins on both the deep sand and the mid-slope soils.

Grain quality results showed very little variation between all treatments with test weights between 60.8 and 63.6, protein between 13 and 13.9, moisture between 11 and 11.2 and screenings between 7.6% for Jockey and 9% for Dividend © 130 mI/l 00kg.

Weeds external to a cropping area (ie; along fence lines and roadways) are a known problem. They impact negatively upon a cropping operation in a number of ways; ie,

• Pest insects - Weeds can provide refuge for insect pests and act as a point source of distribution into a cropping area.
• Diseases - Weeds can act as a host for crop disease. When an infected weed is fed upon by a pest insect (e.g. aphid) and the pest insect then feeds upon a plant within a cropping zone the disease is transferred to the crop.
• Seed - Weeds external to a cropping zone provide a source of seed that can enter and infest a cropping area.
• Mice - Weeds external to a cropping area provide food, moisture and refuge for mice.
• Herbicide resistance - Weeds external to a cropping area do not generally receive the same levels of control as weeds within a cropping area, which can assist in the development of herbicide resistance.
• Green bridge - Weeds that perpetuate external to a cropping season provide what is termed as a “green-bridge”. This green bridge is known to enable pest insects and diseases to survive as well as provide a source of weed seed for future in-crop infestations.

• In glasshouse trials, which grew normally and produced grain when soil dressings of copper sulphate replied to surface soil from the field sites.
• There is therefore no inherent characteristics of the soils which makes fertiliser copper unavailable for plant uptake.
• The pattern of rainfall at each field site was compared with the rate of development of the wheat. When symptoms of coffered deficiency appeared in negligible grain yields occurred despite fertiliser application no effective rain fell in the 20 days before the plants reach the boot stage of growth.
• When soil dressings improved grain yield effective rainfall occurred within 14 days prior to booting.
• It is postulated that wheat cannot absorb sufficient copper for normal growth and development from a dry fertiliser zone.
• When the zone is dry just before booting wheat suffers an acute deficiency of copper during a critical phase of pollen formation resulting in infertile pollen.

Soil type and topography/drainage will be the major factors that determine the effectiveness of the raised bed system.

• Phillip Adams has been working on raised bed farming for the past seven years and is convinced the system has significant benefits.
• Raised beds increase the quantity of organic matter in the soil which is of great importance in improving soil structure and promoting germination and growth.
• All land is suited to raised beds, however paddocks where excess water is a problem (eg. sodic soils prone to waterlogging) will benefit the most. The aim of raised bed farming is to produce loose soil beds where water can drain off to prevent waterlogging in the root zones, to provide adequate drainage, and to store excess water for use when conditions turn dry.

The trend to higher grain yield and deeper root growth in the deep rip treatment suggests that in heavier soils deep ripping may be beneficial to encourage deep rooting and deeper infiltration of water following rainfall events. While the observations relate to responses in the year in which the treatments were imposed, it will take further cropping cycles to determine the stability and sustainability of these responses. The pattern of rainfall distribution and the overall soil water dynamics may have also had an impact on the yield responses. While the initial response is promising, further testing would be required before recommendations could be made. 

The first-year response of a shallow cultivation treatment (as bed renovation) was not significant and barley yield was marginally superior in the control.  This is in contrast to the results at Gnarwarre where opposite trends were observed, but on a lighter soil. In the heavier Lismore soils, it may be worth looking at the deep ripping option as the higher rainfall compared to Gnarwarre may result in a different soil water use pattern. The shallow cultivation treatment also should be monitored for a further year or two until the system achieves equilibrium. 

• Raised beds increase productivity on saline, waterlogged land along with fertiliser and fencing our wildlife.
• Potential issues: uneven bed formation can make seeding difficult, saline soil may be brought to the surface, leached salts may cause damage.

• In 2004 the organic system had the lowest wheat yield and the highest screenings.
• The 2004 gross margin showed that the Albrecht, Soil Management Riverina and BioAg systems made a small profit.
• The Conventional, Soil Management Riverina and Organic systems have the best long-term (2000-2004) average gross margins, although they are all negative.

• Liming and spading had a significant effect on soil pH. The untreated plots (no spading and no lime) had a soil pH that declined from 5.5 to 4.3 down the soil profile.   Simply spading the soil, without lime application, lowered the soil pH of the topsoil to because acidic subsoil is mixed with the top soil.  Liming, without spading, has significantly increased pH levels on topsoil to 5.8 but no effect at depth. Liming together with spading has improved the soil pH at depth.
• Due to variability at seeding and weed control the impact of soil amelioration on productivity of the wheat varieties is not conclusive (CV = 16%). Liming (averaged across variety and spading), reduced yield from 3.2 t/ha to 2.9 t/ha (p=0.009, LSD =0.2). Spading treatments affected seeding depth. This resulted in variable and poor emergence in the spaded treatments. Wheat plant  densities established were 85 plants / m2 in the spaded treatment and 105 plants / m2 in the un- spaded treatment.  Brome grass control was not highly effective and variable across the site. These factors will have influenced the large variability in treatment effects. However future cropping across the trial area may indicate the treatment effects.
• Corack and Mace were significantly higher yielding than Emu Rock, however black point is a risk factor for Corack. The other varieties performed similarly.
• Spading treatments were carried out within a short period prior to seeding and plots were not rolled. This will have had a large influence on the variability of grain yield at the site. To improve future trial research liming and spading need to be carried earlier in the year for soil to settle before seeding or roll soil after spading to prevent machinery from sinking in soft soil.

• Benefit cost analysis using the small yield benefit (up to 100kg/ha) found on shallow ironstone areas in this paddock (0-3cm topsoil over ironstone sheet) showed a nil to negative return on investment.
• In 2019, the season was too dry to measure a yield response.
• In 2020, in-season data was collected but the season was dry with a hard finish (0.7t/ha paddock average) and no yield difference was measured. While the Reefinator may increase plant available water capacity, recent seasons have provided very little moisture.
• Yield maps are critical for ongoing monitoring of paddock machinery-scale treatments where soil variability can confound treatment effects.

Key findings

• Yield loss from crown rot ranged from not significant in five of the bread wheat varieties, the barley variety CommanderA and the durum variety JandaroiA up to 12.9% in the bread wheat variety EGA GregoryA.

• The recently released durum variety DBA LillaroiA produced a protein level of 15% which was over 1% higher than the two other durum entries JandaroiA and 190873.

• Crown rot infection did not significantly impact on the level of screenings in any of the entries due to limited expression under the wet seasonal conditions at this site in 2016. However, genetic differences were evident with screening levels which ranged from 3.2% in the durum line 190873 up to 17.6% in the bread wheat variety BeckomA.

Conclusions

Cereal crop and variety choice affected yield in the absence and presence of crown rot infection, which differed by 2.26 t/ha and 2.24 t/ha, respectively between the best and worst entries. The three durum entries were higher yielding relative to bread wheat and barley entries in both the added CR and no added CR treatments at this site in 2016. This was likely due to seasonal conditions (near full soil water profile at sowing plus 472 mm of in-crop rainfall), which limited crown rot expression.

Cereal crop and variety choice still provided a 9% to 35% yield benefit over growing the susceptible bread wheat variety EGA GregoryA under high levels of crown rot infection at Tamarang on the Liverpool Plains in 2016. This can maximise profit in the current season but will not reduce inoculum levels for subsequent crops, because all winter cereal varieties are susceptible to crown rot infection. Winter cereal crop and variety choice is therefore not the sole solution to crown rot, but rather just one element of an integrated management strategy to limit losses from this disease.

This year's site, being responsive to nitrogen, fits with the other responsive sites at the lower end of the range of deep nitrogen test results. However, as the site with the highest deep nitrogen test result recorded a response to nitrogen in another year, more sites are required to further clarify the relationship. 

• Lime is the most effective amendment to increase pH and reduce exchangeable aluminium (Al).
• Deep placement of organic materials had a limited effect on soil pH, but reduced exchangeable aluminium percentage (Al%) significantly.
• The combination of lime with organic materials could facilitate alkalinity downwards in the soil profile in the short term.
• However, applying a large amount of organic materials could acidify soil over a longer term due to nitrification.
• No crop response was observed over the past three years due to severe drought conditions.

• Deep placement of organic amendments (e.g. lucerne pellets) did not increase soil pH as high as measured in laboratory/glasshouse experiments, but it did reduce exchangeable aluminium (Al) significantly at 10–20 cm and 20–30 cm, indicating that the organic amendment would relieve Al toxicity by combining Al3+ to form insoluble compounds, hence reducing toxicity to plant growth.

• There was a large crop yield response to deep organic amendments in year 1 due to extra nutrients supplied from the lucerne pellets, but no crop response was detected in year 2, partly due to lack of soil moisture during the crop growing season. To date, soil treatments have had little effect on soil water.

• Soil chemical, physical and biological properties will continue to be monitored to understand the soil–plant interactions, the factors driving the differences in crop response to the various treatments, and the residual value of the amendments over the long-term.
 

In 1978, a residual value trial in which it is possible to compare the effectiveness of previuos applied Mn with cuuently applied Mn.  The Mn sulfate at 15, 30 & 60 kg/ha in 1978 produced maximum seed yield. The 15 & 30 kg Mn sulfate applied in 1982 produced the same maximum seed yield as Mn applied in 1978.  However, the 15 kg/ha of Mn sulfate applied in 1978 & 1982 still resulted in 11 - 16% split seed compared to the nil Mn that had 40% split seed. THe 30 kg Mn sul /ha reduced split seed to <5%.

The Mn concentration in whole shoot was 34 mg/kg; indicating Mn deficiency The Mn concentration in whole shoots with 15 kg Mn sul/ha was similar (80 mg/kg) for 1978 and 1982 applications.

THese results suggest that the residual value of soil applied Mn is greater than originally thought 

• Tested effect of rates, methods of application and residual effects of zinc oxide on hybrid maize XL45.
• Zinc was either broadcast or drilled at initial rates of 0, 5.6, 11.3 or 38 kg Zn/ha and 0 or 5.6 kg Zn/ha in subsequent seasons.
• In most seasons, treatment with zinc almost doubled grain yields.
• Broadcasting and working in was more effective than drilling zinc with the fertilizer.
• Residual effects of the initial 5.6, 11.2 and 38 kg Zn remained evident throughout the 6 years and the higher rates continued to produce highest yields.

Rates nil to 5 kg Zn/ha applied in 1970. Results for 1977.

Zn applied in 1970 barely detectable although application of plain super at 250 kg/ha /yr since 1970 maintain Zn levels for near maximum yield of pasture..

The author indicated the following:  

Suggestion that results indicated need to reassess the Zn requirement of a wide on inherently Zn deficient soils. This is particularly so in the absence of Zn via the Zn impurities in super from traditional sources of rock phosphate. It maybe highly likely that some future date we may have to rely on low Zn containing Zn phosphates .  Unless more information is obtained in advanced there could be serious losses due to Zn deficiency some time in the future.

Residual effects from soil nitrogen can be observed in the following cereal crop whcih makes a good case for utilising pulse innoculants

1. Terbyne® Xtreme® and Valor® provided the best residual control of common sowthistle as stand-alone residual herbicides and as mix partners with ‘grass active’ herbicides.
2. Group K, Group D and Flame® provided the best residual control of grass weeds as standalone residual herbicides and as mix partners.
3. Herbicide mixtures provided improved control over individual products and are likely to provide more wide-spectrum control of a range of weed species.

• P fertilisers applied in 2006 did not improve grain yield in 2007, even at the high P rate (18 kg P/ha).
• In terms of residual value, there was no difference between granular and fluid P.
• 2007 applied fluid P (TGMAP) at 6 kg P/ha increased dry matter at GS30 from fresh granular P and control treatments.
• Soil testing is a useful tool for estimating P status in the soil.

• It was not surprising that no response to sulphur was obtained, when we consider that the KCI sulphur level in the soil rose from 5-7 mg/kg before bed forming to 16 mg/kg after bed forming. 
• For further discussion please see the attached trial report.

  Key findings:

Yield in the presence of crown rot was generally barley > bread wheat > durum across both sowing times, but significant differences were evident between varieties.

• Barley, bread wheat and durum varieties differ in their extent of yield loss from crown rot and their actual yield and grain quality (screenings) in the presence of this disease.
• However, all varieties are susceptible to crown rot infection and will not significantly reduce inoculum levels for subsequent crops. Variety choice is not a sole solution to crown rot.

Conclusions

• Sowing date and variety maturity choice is a balance between frost risk and terminal heat stress in the northern grain region. Both can have a significant impact on grain yield. No frost damage was evident at this site in 2014 with either sowing time but terminal heat stress did occur which was more severe during grain filling with the second sowing time. A three week delay in sowing time resulted in an average 24% reduction in yield across the winter cereal entries.  Later sowing pushed grain-fill too far into hotter conditions. This can reduce yield by itself but if there is also an underlying issue with crown rot then delayed sowing significantly exacerbates the expression of this disease with negative impacts on both yield and grain quality.

  Varieties do differ in their extent of yield loss from crown rot and in their relative yield in the presence of high levels of infection, which is often referred to as tolerance. This is a function of a varieties level of partial resistance to infection but appears to also interact with its environmental adaptation and maturity relative to the timing of stress (moisture and heat) which exacerbates the expression of crown rot. Generally quicker maturing barley, durum and bread wheat entries were higher yielding in the presence of crown rot infection in this trial. This does not necessarily mean that these varieties have improved levels of resistance to crown rot infection but rather their quicker maturity allowed them to minimize stress during grain filling relative to longer season entries, reducing the expression of crown rot.

  If forced into planting a cereal crop in a high crown rot risk situation then some barley varieties may provide a yield advantage over bread wheat in that season, as long as early stress does not occur. Some of the newer bread wheat varieties do appear to be closing this gap to some extent. Barley tends to yield better in the presence of crown rot infection due to its earlier maturity relative to bread wheat, providing an escape mechanism which reduces its exposure to moisture stress during the critical grain filling stage. However, a key message is that this decision is only potentially maximising profit in the current season. Growing barley over bread wheat will not assist with the reduction of crown rot inoculum levels as barley is very susceptible to infection. Significant yield loss is still occurring in the best of the barley and bread wheat varieties in the presence of high crown rot infection. Variety selection can improve yield in the presence of crown rot, though all varieties still suffer yield loss, which can maximise profit in the current season but this will not reduce inoculum levels for subsequent crops. Winter cereal crop and variety choice is therefore not the sole solution to crown rot but rather just one element of an integrated management strategy to limit losses from this disease.

• 10 chickpea genotypes were grown in the field with and without added zinc.
• Zinc sulphate was applied to the soil at sowing and later as a foliar spray at the start of flowering.
• Zinc fertilisation increase shoot dry matter by 13% at maturity.
• There were differences between cultivars in zinc efficiency.
• Gains in yield by improved to sink efficiency are possible in chickpeas.
•  The ranking of cultivars was consistent between sites and in pot studies in the glasshouse.
•  Significant responses to zinc fertiliser confirmed that zinc deficiency was a limitation to chickpea yield.

• The critical zinc concentration in shoots ranged from 22 to 29 mg /kilogram across the 5 durum varieties.
• There was no difference in shoot zinc concentration of the 5 varieties within any of the zinc treatments, ranging from 0.025 to 5 mg / kilogram of soil.
• There was some evidence that zinc sensitive genotypes were more likely to suffer from crown rot.

• The Italian ryegrass responded well to phosphorus additions in the range of 15-60 kg P/ha and required the higher rates to be applied unless nitrogen, potassium and sulphur were also included.
• In regard to the addition of potassium, the relatively wet year meant there was unexpectedly no negative affect on plant establishment by banding potassium fertiliser in the soil at sowing which is generally not recommended.

Potassium levels are low in this soil and this site should have been responsive to applied potassium, however due to seasonal and soil conditions there where no differences between treatments in this trial. The very dry June-August had a marked impact on crop growth, particularly tillering. This can be seen by the lack of differences in the head counts taken in September. Very hot conditions in early August also affected flowering in wheat and limited any response in grain yeild with later rains. Soil penetrometer readings in the paddock near the trial site showed hard pan and this in conjunction with the pH and Aluminium levels below 10cm would have restricted root growth and limited the wheat plants ability to access soil miosture at depth during the dry winter period. Without yield responses to applied treatments, crop return decreased as fertiliser rates increased.

• Five representative sites with no history of copper application were selected on each of five main soil types in the district.
• Four treatments (replicated 4 times) were established; Nil and 75 g/ha of foliar copper applied at Zadox scale 23, 41 and 23 + 41.
• Anthesis and harvest dry matter production and grain yield were determined by quadrat cuts of 3mL/plot. Al, A2 and 81 horizon soil samples were taken for chemical analysis • Copper application resulted in a significant increase in grain yield on soil types 2 and 5, attributable to significant increases in grain weight on soil type 5, and grain number per head on soil type 2.
• These soils were geologically the oldest of the five tested and had the lowest average level of EDTA copper.
• Time of application was not important and a second application did not increase yield further.
• There were no early symptoms of Cu deficiency on any sites and foliar application of copper at tillering produced no change in either visual appearance or anthesis dry matter production.
• Deficiency symptoms only became apparent at stem elongation when two sites displayed minor wilting.
• In addition to identifying the two soil types with suboptimal copper supply to wheat, this experiment highlights the pitfalls of relying on visual detection of copper deficiency.
• Areas of subliminal but significant copper deficiency may go undetected by farmers who rely on this method.

• Trial sowing at 11 June was later than optimal but plant growth was showing strong response to nitrogen (N) and some response to potassium (K) at 28 August.
• By harvest, Mace wheat showed significant grain yield response to nitrogen application but potassium response had moderated.
• No significant differences were seen from Cu application.
• Late sowing decreased yield potential from the start. Harvest yields ranged from 2 to 3 t/ha, with maximum yield and $/ha return at 80 kg N/ha and 12.5 kg K/ha.

There was a significant difference in response to irrigation on the flat ground and raised beds (Table 2). Grain yields on the flat ground only increased slightly with irrigation and this was not significant. On the raised beds there was a progressive increase in yield with increasing irrigation although there was not statistically significant difference between the two irrigated treatments. Initial examination of data from Gopher tubes shows greater drying of the soil profile on raised beds.

• Wheat yields in the poor, medium and good zones in response to low, medium and high inputs respectively did not differ significantly in 2011.
• Over a 3 year wheat-canola-wheat rotation there has been no measured production benefit from applying 6 kg/ha of P on the good soil type as opposed to nil P on a shallow constrained soil.