• The average grain yield (header harvest) of the trial was 17.12t/ha with no indication that increased nitrogen rate (from the use of pre-drill urea) significantly increased yield when 207kg N/ha was subsequently applied in crop as fertigation.
• The lowest plant population 79,287 plants/ha resulted in the lowest yields with no grain yield difference between 91,864 and 103,620 plants/ha. 91,864 plants/ha was the most profitable.
• Normalised differential vegetative index (NDVI) assessments indicated that ground cover was significantly lower in the lowest plant population across all assessment timings up to V8.
• The most efficient recovery of nitrogen applied was recorded with plant populations of approximately 92,000 plants/ha with N applied by fertigation totalling 207 kg N/ha.

• Although increasing the frequency of N applications appeared to slightly increase grain yield (machine harvested) compared to all “up front” in seedbed yield differences were not statistically significant.
• As a general comment, timing of N application did not affect the grain yield, whether it be all up front or split over 4 timings up to V6.
• The nil applied N treatment yielded 9.49t/ha.
• However N content of the grain at harvest was greater where split applications involving later timings were compared to all the nitrogen applied at sowing indicating greater N fertiliser efficiency
• However, unless there is a premium for the maize protein in the grain resulting from later N timings the difference may be of little value to the grower.
• Soil N prior to sowing and watering up was 25 kg N/ha (0-60cm). The nil treatment contained a total of 147 kg N/ha at harvest, suggesting in-crop mineralisation resulted in 122 kg N/ha released to the crop.

• The highest grain yield (machine harvested) achieved was 16.36 t/ha with the applied N rate of 240 kg N/ha in a crop producing 30.63 t/ha dry matter at 50.45% harvest index.
• N applications above 240kg N/ha were uneconomic in the trial.
• The nil control treatment yielded 10.89 t/ha in a crop producing 26t/ha dry matter at 51% harvest index.
• Available Soil N prior to sowing and watering up was 34 kg N/ha (0-60cm). The nil control N offtake at harvest was 241 kg N/ha, suggesting in-crop mineralisation resulted in 207 kg N/ha of the N taken up.
• At the highest level of N (560kg N/ha) there was no advantage to applying 80 Kg N/ha of the dose very late at tasselling.

• Header grain yields averaged 18.2t/ha with no yield benefit observed from applying pre-drill urea in the trial when N was applied post sowing as fertigation.
• In a trial with an overall dose of post sowing N of 207 kg N/ha applied via fertigation there was no significant yield increase from the earlier pre-drill N applications of between 0 – 315kg N/ha.
• The economic optimum level of nitrogen applied was 252kg N/ha (45N pre-drill + 207kg N as fertigation).
• No significant differences were recorded in total dry matter (DM) content at V6 or at harvest with an average DM content of 34.6t/ha.
• The N content at harvest revealed an average N content of 462kg N/ha with a range of approximately 415-530kg N/ha in the crop, but there were no statistical differences.
• The N offtake at harvest indicated soil mineralisation provided up to 165kg N/ha to grow the crop with lower N efficiency recorded from applied fertiliser at higher overall N rates.
• There were no significant differences in test weight (mean 81.1) or harvest index (mean 51.7%).

• With an average grain yield of 18.28t/ha there were no significant differences in header grain yield from varying nitrogen rate or timing of prilled urea (46%N).
• Where no nitrogen was applied early in the season a significant decrease in nitrogen content was observed in the stalk of the plants at harvest, but there no influence on grain N content.
• Test weight was significantly reduced when only 207kg N/ha was applied to the crop, there was no significant benefit in test weight when the highest rate of nitrogen was applied.

•  Delaying post sowing applications of nitrogen (92 kg/ha N) to the flag leaf stage for both Kellalac and MacKellar at the Gnarwarre site, resulted in the best grain yield and grain quality.
• Application of nitrogen (35 kg/ha N) to barley at the early jointing stage (GS32), gave the best grain yield and quality at Gnarwarre.
• Late nitrogen applications appeared to result in more flower sites (florets) filling with grain for both wheat and barley. 
• For further conclusions please see the attached trial report.

• Early sulphur application supported higher tiller numbers although this did not translate into yield
• Site was very responsive to at least 79kg nitrogen application.
• An additional 50kg urea (23kg N), resulted in slightly higher protein readings.
• Site was unresponsive to sulphur application.
• Timing and splitting of in-crop fertilisation conferred no yield advantage • Good utilisation of applied N and S in spite of high rainfall year.

To manage N2O emissions in low to medium rainfall environments, growers need to match nitrogen supply to crop demand. Lowest emissions were measured where nitrogen levels were least, while highest emissions occurred where nitrogen levels were greatest. Applying late nitrogen to increase wheat protein is not economic when segregation price differentials are small.

• Work conducted in low and medium rainfall environments indicate that N2O emissions are low from an overall national perspective. • Results showed that there was no clear response of N2O emissions to nitrogen applied at sowing and post sowing. • High pre-seeding soil mineral nitrogen raises the possibility of higher N2O losses over the fallow period following significant rainfall.

• Work conducted in low and medium rainfall environments indicate that N2O emissions are low from an overall national perspective. • Results showed that there was no clear response of N2O emissions to nitrogen applied at sowing and post sowing. • High pre-seeding soil mineral nitrogen raises the possibility of higher N2O losses over the fallow period following significant rainfall.

Preliminary results showed the level of nitrous oxide emissions did not increase over the 2013 winter as a result of near capacity soil water contents coupled with increased nitrate nitrogen levels resulting from seeding and in-crop nitrogen applications on the canola compared with a pulse crop and legume pasture.

Preliminary results showed the level of nitrous oxide emissions did not increase over the 2013 winter as a result of near capacity soil water contents coupled with increased nitrate nitrogen levels resulting from seeding and in-crop nitrogen applications on the canola compared with a pulse crop and legume pasture.

• Chickpea and lupin failed to nodulate without inoculation.
• Inoculation formula had minimal effects on growth and yield of pulses at this site.
• Peat and liquid formulations were consistently reliable inoculants across all pulses based on nodulation and grain yield
• Differences measured in nodulation were not reflected in differences measured in crop growth and grain yield, suggesting soil nitrogen reserves were sufficient to make up most of the crop’s needs.
• Field pea and lentil rhizobia appear more widespread in this environment and better adapted to the acidic soils, while chickpea rhizobia appear less adapted.

• This protein levels achieved in this trial are very low, indicating possibly an acute nitrogen deficiency problem.
• An N deficiency however was not evident in the trial with no noticeable interveinal chlorosis.
• For further discussion please see the attached trial results.

• Noodle wheat production was not suited to this paddock due to the high soil nitrogen levels. Milling wheat production was a much better choice for this paddock as evidenced by the performance of Mitre. High soil nitrogen levels resulted in protein levels too high for the noodle varieties to achieve their ASWN potential for all plots at the site except Lorikeet with no urea at sowing.

1. The district practice Baseline system is the most profitable to date. However apart from the 2016 winter crop there is very little difference between the seven grain systems.
2. Water use efficiency is higher for cereals than pulses and is highest in high-yielding crops.
3. Subsoil constraints are limiting PAW extraction by pulse crops.

1. Summer break crops reduced levels of cereal soil-borne disease and allowed more even and higher yielding wheat crops in 2018, however they were the least profitable.
2. Root lesion nematodes continued to decline, even under susceptible crops due to the dry growing conditions of 2017 and 2018.
3. Higher nitrogen supply did not increase plant uptake or yield due to low in-crop rainfall, but this extra nitrogen is still available in the soil profile for following crops.

• Sowing date, uniform sowing depth and weed control are just as important to maintain yields in a wide row system as in conventional systems.
• The results in 2001 indicate that the wide-row system has potential at the yield levles typically achieved in the central-northern Mallee.

• The site was very responsive to nitrogen (N) fertiliser. Increasing N inputs from 12 to 75 kg N/ha increased yields by about 0.36 t/ha
• NUlogic suggested very little response to P and K after soil testing. It is important to be soil testing at least every 3-4 years so that fertiliser rates recommended are applied for maximum economic returns to the grower.
• Tissue tests on the 3rd July indicated marginal S deficiency in the no S treatments but there was no yield response.
• Wind and rain after seeding caused furrow fill resulting in poor germination (5-15 plants m²).
• Yield potential  probably limited by low soil pH
• Decile 1 rainfall year for the area, interpret results accordingly.
• Quality analysis not yet available.

• Conventional tillage enhances soil organic carbon (SOC) turnover with the potential to simultaneously increase plant available nutrients [nitrogen (N), phosphorus (P), sulfur (S)] in the soil compared with no-till and perennial pasture.
• Across farming management practices and under ideal soil moisture, soil organic matter (SOM) could have supplied up to 45 kg N, 16 kg P and 19 kg S/ha in the absence of plant carbon (C) input.
• Over a longer period (126 days), particularly if there is a lack of plant C input (e.g. a normal fallow period), any P or S released via native SOM turnover over a shorter period (e.g. over 30 days) would have been immobilised by microorganisms and/or adsorbed to soil minerals, hence decreasing P and S availability for crop uptake

Variable rate fertiliser application has a real and profitable place in the Mallee when combined with good paddock science. The precision technology gives the ability to examine the yield data for many effects including other possible influencing factors such as elevation, slope aspect or orientation to the sun, and probably many others.

• The omission (absence) of nitrogen and phosphorus fertiliser inputs at the Inverleigh canola trial site caused a statistically significant reduction in canola grain yield
• Visual biomass differences at the Glenthompson wheat site were noted during the season, but did not translate to yield
• Low rainfall and high temperatures in the 2015 spring reduced the response of crops to the presence or absence of nutrients

• Previously observed benefits of improved N use efficiency where Zn is supplied with the N were not captured in the 2017 season.

There may be an opportunity to enhance phosphorus uptake in wheat following an albus lupin crop.

• It was difficult to see the carryover of residual P into 2003 in this trial as some plots were affected by crown rot or common root rot (still to be determined).
• The maximum wheat yield was achieved when 5 kg P/ha was applied in 2003 on top of 11 kg P/ha applied in 2002.

• Canola yields in 2003 were below average, mostly less than 0.5 t/ha.
• No yield response was reported with increased rates of P and N fertiliser.

• Time of sowing had a greater influence on oat grain and hay yield, and oat grain quality than variety selection or level of applied nitrogen in 2015.
• High screenings limited the ability of grain to meet Oat1 quality standards, this was due to the detrimental impact of delayed seeding and/or applied nitrogen in excess of that required in lower rainfall environments.
• Applying more than 20 kg N/ha did not improve the return per hectare ($/ha); rather, applying 80 kg N/ha consistently reduced return per hectare ($/ha).
• Screening of Williams and Carrolup were more sensitive to applied nitrogen than WA02Q302-9, Bannister and Yallara.
• WA02Q302-9 appears a suitable replacement for Yallara and Carrolup, and should achieve a better hectolitre weight than Bannister at similar or lower yields.

 New variety Bilby  (breeding line 06204-16) out-yielded Carrolup (by 0.3 t/ha), but did not out-yield Williams, and was between Williams and Carrolup in grain quality. 

Similar to 2017, a mild finish to the growing season meant all varieties met Oat1 quality specifications, and reduced the response of varieties to changes in plant density and applied nitrogen.

 

 New variety Bilby  (breeding line 06204-16) out-yielded Carrolup (by 0.7 t/ha), but did not out-yield Williams , and had lower grain quality than Carrolup in grain quality. 

Similar to 2017, a mild finish to the growing season meant all varieties met Oat1 quality specifications, and agronomy had a reduced impact on grain quality.

 Kowari and Williams yielded similarly, and out-yielded newly accredited variety Bilby  (breeding line 06204-16) (by 0.15 t/ha) and Carrolup (by 0.25 t/ha).

Bilby was the most sensitivity to increasing nitrogen, with N increasing from 0 to 60kg N/ha significantly reducing Bilby’s hectolitre weight.

Nitrogen application to optimise waterlogging recovery

Nitrogen application to optimise waterlogging recovery

Nitrogen application to optimise waterlogging recovery

When making oat varietal decisions, it is important to consider various factors. These include the environmental suitability, end use (milling, feed grain, grain and graze or hay production) and likelihood that the required grade/quality will be achieved, potential disease issues (both root and foliar leaf diseases) and yield potential.

When making varietal decisions with oats, need to take into account various factors, including the environmental suitability, end use (milling, feed grain, grain and graze or hay production) and likelihood that the required grade/quality will be achieved, potential disease issues (both root disease and foliar leaf diseases) and yield potential.

In a year with an outlook of a dry finish and lack of grain fill due to limited moisture, high temperatures or frost, the ability to take advantage of early crop growth through oaten hay is a reasonable risk management tool to consider.

• Hay crops can be used for both risk management and as part of an integrated herbicide resistant grass management program.
• Paddock selection is important. It is best to select a paddock with a low weed burden; there are limits to the amount of ryegrass that is accepted for export oaten hay.
• For quality oaten hay it is important to minimize stem thickness; this can be achieved by the use of high seeding rates. Cross sowing may be necessary to ensure windrows are supported by stubble for bailing, especially if sowing using wide row spacings.

• For the fourth year running, on-row sowing proved it has potential as a brome management tool on non-wetting sands, reducing brome grass seed set by 55%.
• The use of trifluralin with metribuzin reduced the brome density in July but did not reduce seed set.
• On-row sowing resulted in more soil water and nitrogen supply potential near the crop,  improved crop establishment and higher crop biomass.
• On-row sowing did increase root disease incidence, but there were low levels of disease for both on- and inter-row sowing in 2017.

All tillage treatments had a little effect on the management of SWR and plant establishment in the severe water repellent gravel sand at Moora. Nevertheless, yield improvements were recorded, in particular with the “Large offsets” and the “Modified one-way with standard discs” treatments.

At this stage, it is not possible to clearly state what changes drove the yield increase. Given the little effect that the cultivations had on the SWR it is possible that improved soil structure, increased nutrient availability and nitrogen mineralisation may have played a role on the increased productivity.

The yield potential of the canola crop in 2015 was low given it was sown relatively late, plant numbers were low and there was a dry finish, this may have compromised the response to the tillage treatments. Observation of the trial in the following growing seasons and the response of a cereal crop in 2016 will help us to better understand the long term effect of the treatments on crop growth.

• Onion weed is a significant pest and competitor of medic pastures. In mixed farming systems, control in the pasture phase is often reliant on cultivation.
• None of the herbicides evaluated in this trial provided adequate onion weed control in the medic pasture phase without unacceptable reduction in medic biomass.
• The use of non-selective herbicides and their mixes, combined with strategic cultivation if required, is still the most effective short term strategy in reducing the impact of onion weed on crop/pasture systems on Eyre Peninsula (EP).

The response to nitrogen in these trials should encourge the application of urea for wheat crops in these regions when the deep soil N test shows that the soil is low in available N prior to sowing in relation to the target yield set for the crop.

Opportunistic summer cropping can make use of summer rainfall that may otherwise be lost to evaporation.

In this instance the opportunistic crop of canola in 2011 has proven the more successful rotation. At the beginning of the season, given the rainfall during harvest, the soil had comparable moisture at depth irrespective of the crop in 2011. The weed break given by the canola was significant, very few grass weeds coming through in old canola plots. The management of weeds proved telling in this trial. Much of the potential wheat yield was removed by the brome grass in the wheat on wheat plots.

Wheat on wheat this season achieved approximately 16kg/mm of rainfall. Wheat growing without the competition of weeds on the canola plots achieved in excess of 19kg/mm. Making crude assumptions that wheat on fallow grew at 19kg/mm, and the additional 400kg/ha yield was the result of additional moisture alone, then there was approximately 21mm of additional moisture in the fallow plots. Fallow had more moisture available closer to the surface than the other plots though not significantly more moisture throughout the remainder of the profile.

In 2012 wheat on fallow plots returned $100 more than wheat grown on either wheat or canola residue. This recouped the $40 loss from the 2011 fallow with additional profit. But fallow did not result in the greatest total profit over the two seasons of the trial. The extra production on the fallowed treatments was unable to make up the opportunity cost of not growing a crop in 2011. This is not unexpected given the high crop yields achieved in 2011.

In this instance the opportunistic crop of canola in 2011 has proven the more successful rotation. At the beginning of the season, given the rainfall during harvest, the soil had comparable moisture at depth irrespective of the crop in 2011. The weed break given by the canola was significant, very few grass weeds coming through in old canola plots. The management of weeds proved telling in this trial. Much of the potential wheat yield was removed by the brome grass in the wheat on wheat plots.

Wheat on wheat this season achieved approximately 16kg/mm of rainfall. Wheat growing without the competition of weeds on the canola plots achieved in excess of 19kg/mm. Making crude assumptions that wheat on fallow grew at 19kg/mm, and the additional 400kg/ha yield was the result of additional moisture alone, then there was approximately 21mm of additional moisture in the fallow plots. Fallow had more moisture available closer to the surface than the other plots though not significantly more moisture throughout the remainder of the profile.

In 2012 wheat on fallow plots returned $100 more than wheat grown on either wheat or canola residue. This recouped the $40 loss from the 2011 fallow with additional profit. But fallow did not result in the greatest total profit over the two seasons of the trial. The extra production on the fallowed treatments was unable to make up the opportunity cost of not growing a crop in 2011. This is not unexpected given the high crop yields achieved in 2011.

• Continuous cropping can be sustained for decades, but requires careful management.
• A larger proportion of N supply as fertiliser will be required over time even when grain legumes are included in crop sequences.
• Herbicide resistance develops faster under continuous cropping. Integrated management to keep key weed populations at very low levels is essential for long-term viability.
• Suitably diverse crop and end-use portfolios and flexible management help build resilience to climate and crop price shocks.

There was no response to fungicide in this trial and few significant effects on grain quality. Disease levels were extremely low and a stem green area score at senescence revealed no consistent preservation of green tissue with the use of fungicides.

Again the majority of individual treatment responses to fungicide are positive but not statistically significant, indicating that there is a
trend but it is small. Barley however, poses a dilemma in that the single spray options early and late do not optimise performance against early Scald and late leaf rust infection, as such it is difficult to avoid spraying twice if both diseases pose a threat. In addition, if the rate of both sprays are cut to a bare minimum the results are inferior in terms of disease control. Triazoles are generally not as effective against Scald and diseases such net blotch, by comparison to the rusts.

• Highest yields were obtained when flowering started in early to mid-August. Treatments that flowered in July were affected by frost and treatments that flowered in September were affected by heat and drought.

• The strongest yield response to nitrogen was on treatments that flowered in early to mid-August.

• Hybrids tended to recover better from frost damage than open-pollinated (OP) triazine tolerant (TT) varieties, but flowering date and nitrogen management were more important to maximise yield potential than variety type.

• The highest oil concentration was obtained from varieties that flowered in early to mid-August.
 

• Standard inoculation practices are unlikely to deliver satisfactory nodulation where pulses are sown into dry soils.
• Pea and chickpea sown late (26 June) had the higher nodulation and crop production than those sown dry. Where the soil remained dry for 20 days after sowing nodulation was poor, regardless of the inoculation strategy used.
• Nodulation of pea was low regardless of sowing time at Minnipa in 2018. Both peat applied to seed and granule formulations resulted in similar nodule numbers per plant.
• Nodulation can be improved when dry sowing if inoculation rate of peat is increased. Doubling the rate of inoculation significantly improved pea nodulation. 
• The performance the rhizobial granules was inconsistent. A granule produced at SARDI was more effective in one experiment, but not the other. Two commercial granules provided no advantage compared to peat applied to seed.

EGA Wedgetail can successfully be grown for grain only or dual purpose use and achieve yields competitive with recently released main season cultivars sown in May.  Growers wishing to graze EGA Wedgetail should use high plant densities (at least 100 plants/m2 on 305 mm row spacing, higher on narrower spacing) and some N fertiliser at sowing (particularly if soil mineral N is low) to maximise forage yield.  Gorwers who wish to grow EGA Wedgetail for grain only should defer N fertiliser application until after Z30 to reduce early vegetative growth.  Neither of these experiments or any others during the early sowing project have found a yield benefir from reducing plant populations, and target plant density should be kept at 100-150 plans/m2 (less on wide rows, more on narrow rows) in order to better compete with weeds.

• Phosphorus response trials were undertaken on barley, wheat, canola, lentils, faba beans and field peas at four sites across the Wimmera and Mallee over the past three seasons.
• There was no consistent response to the rate of phosphorus applied in wheat, barley, canola, lentils and field peas on sites that had a good fertiliser history (a positive P balance) and good P fertility (Colwell P of 15ppm or more). Faba beans were the exception responding to higher rates of phosphorus (up to 18 kg P/ha) – this was a consistent result over the 2000 and 2001 seasons.
• At the Donald sites, phosphorus rate significantly increased yield. This result was not unexpected as the trials were typically located on soils that were low in fertility (Colwell P <12ppm) and acidic (pH BBwaterB = 6.3).
• Reducing phosphorus inputs to between 6 and 12 kg P/ha will not compromise short-term soil fertility and crop production on sites with good fertiliser history and soil P fertility but further research needs to be conducted investigating the long-term implications of this strategy.

• Phosphorus response trials were undertaken on barley, wheat, canola, lentils, faba beans and field peas at four sites across the Wimmera and Mallee over the past three seasons.
• There was no consistent response to the rate of phosphorus applied in wheat, barley, canola, lentils and field peas on sites that had a good fertiliser history (a positive P balance) and good P fertility (Colwell P of 15ppm or more). Faba beans were the exception responding to higher rates of phosphorus (up to 18 kg P/ha) – this was a consistent result over the 2000 and 2001 seasons.
• At the Donald sites, phosphorus rate significantly increased yield. This result was not unexpected as the trials were typically located on soils that were low in fertility (Colwell P <12ppm) and acidic (pH BBwaterB = 6.3).
• Reducing phosphorus inputs to between 6 and 12 kg P/ha will not compromise short-term soil fertility and crop production on sites with good fertiliser history and soil P fertility but further research needs to be conducted investigating the long-term implications of this strategy.

• Phosphorus response trials were undertaken on barley, wheat, canola, lentils, faba beans and field peas at four sites across the Wimmera and Mallee over the past three seasons.
• There was no consistent response to the rate of phosphorus applied in wheat, barley, canola, lentils and field peas on sites that had a good fertiliser history (a positive P balance) and good P fertility (Colwell P of 15ppm or more). Faba beans were the exception responding to higher rates of phosphorus (up to 18 kg P/ha) – this was a consistent result over the 2000 and 2001 seasons.
• At the Donald sites, phosphorus rate significantly increased yield. This result was not unexpected as the trials were typically located on soils that were low in fertility (Colwell P <12ppm) and acidic (pH BBwaterB = 6.3).
• Reducing phosphorus inputs to between 6 and 12 kg P/ha will not compromise short-term soil fertility and crop production on sites with good fertiliser history and soil P fertility but further research needs to be conducted investigating the long-term implications of this strategy.

• 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.

2018 Season

• At Speddingup, yield of late sown Scepter wheat was highest (3.6 tonnes/ha) in treatment strips that received a 100L top-up of Flexi-N at early stem elongation in early September following a period of waterlogging in August. Yield was lowest (3.4 tonnes/ha) in the treatment to which all nitrogen was applied up front at seeding.
• At Condingup, mid-May sown Scepter wheat yield and grain protein increased as nitrogen application increased, with the Playing the Season treatment seeing the highest (8.4 tonnes/ha) and the Farmer Practice treatment seeing the lowest (6.9 tonnes/ha).
• Moderation of nitrogen applied up front provided the host grower at the Speddingup demonstration site with an opportunity to tailor nitrogen applications to the potential of the season and to address waterlogging issues faced during the season.
• The addition of extra nitrogen following waterlogging at the Condingup demonstration site resulted in improved yield and financial return (after nitrogen input costs had been deducted).
• Applications at stem elongation at Speddingup and as late as full flag leaf to head emergence at Condingup were able to provide yield with an associated positive effect on grain protein.

2019 Season

• There was no statistically significant difference in Scepter wheat grain yield or protein between the nitrogen application regimes applied at the Jerdacuttup, Speddingup and Condingup demonstration sites, despite there being a difference in the rate of nitrogen and timing of application. Each of these sites experienced below average rainfall in 2019 and no waterlogging occurred. Crops at Jerdacuttup and Speddingup were also affected by frost.
• Despite dry growing conditions and exposure to a significant frost in September, Scepter wheat replicates that received the highest rate of nitrogen were the most profitable at the Jerdacuttup demonstration site. The margin between the most profitable and the least profitable treatment was $79/ha while the difference in nitrogen rate applied between these was 54.9kg/ha.
• The difference between gross income achieved from each of the 4 treatments applied at the Speddingup demonstration site was very small but the variation in input costs did affect profitability. The most profitable treatment was the ‘Farmer Practice’ treatment as it had the lowest fertiliser input cost with little yield or grain quality penalty. The ‘Regular Intervals’ treatment was the least profitable of the nitrogen treatments as the input and application costs were highest. Conditions were too dry for the crop to utilize the additional applied nitrogen in this treatment. The difference between these 2 treatments was $72/ha.
• Grain price varied by only $0 to $10/t between nitrogen treatments at the Condingup demonstration site. The most profitable treatment was the ‘Playing the Season’ treatment, with the highest rate of nitrogen applied and the latest application date when the crop was at growth stage Z24/32-33; just prior to flag leaf emergence. The ‘Farmer Practice’ treatment was the next most profitable of those applied, the difference being $29/ha, followed by the ‘All Up Front’ treatment with a margin of $31/ha. The difference between the most profitable and least profitable treatment was $60/ha.

With the varying results from this project, it is evident that response to N is both site and situation dependant. Further work needs to be undertaken to be able to create a broad rule of thumb around the cost/benefit of feeding N to crops on waterlogging soils

• The ‘farmer practice’ strategy ultimately ended up being the best nitrogen strategy for the 2019 season. The crop responded to the applied n up front after good rainfall and resulted in a 5.43 tonne yield and achieved a good return on investment.
• It is likely the crops in 2019 achieved its water limiting yield potential due to the dry finish; therefore, more nitrogen did not improve yield.
• Despite the treatments that received additional N achieving a higher wheat grade, the cost of applying the N in a season with decile 8 pricing, actually reduced profits.
• Growers remain interested in this research and would like to see further results from tactical N applications, especially in wet years and more waterlogged conditions.

• Fertilising above the optimum plant nitrogen (N) demand level reduced N-use efficiency and increased environmental impact.
• Despite receiving 8–9 irrigations as well as several intense rainfall events in a season, there were typically only 3–4 significant nitrous oxide (N2O) flux periods during the season, with most occurring early in the season, i.e. irrigations 1 and 2.
• Other significant N2O emissions events occurred mostly in response to adding in-crop N fertiliser followed by irrigation and/or intense rainfall.
• Initially, higher N2O emissions came from the beds where N fertiliser had been applied pre-sowing. Later in the season, emissions often peaked in the non-irrigated furrows after rainfall and irrigation events, particularly after additional N was added in the irrigation water.
• Farmers’ N rates were at least 25% higher than necessary to achieve the same lint yield in 2014–15, i.e. 50–100 kg N/ha. Less N fertiliser could have produced the same amount of cotton.
• Increasing N rates increased total N2O emissions, especially in prolonged wet conditions.
   

• Nitrous oxide (N2O) emissions respond to large rainfall events.
• Most N2O emissions were generated after the crop was harvested.
• Tillage did not increase N2O emissions significantly in the first two years under wheat and canola.
• Including perennial grass into legume-based pastures would reduce N2O emissions.

• There is an opportunity to use locally available amendments in place of inorganic fertiliser.
• High rates of surface-applied chicken litter tend to have a better yield response than either surfaceapplied compost or inorganic N fertiliser.
• After three years there does not appear to be an advantage using 20 t/ha of amendment compared to 10 t/ha.
• Stability of these organic products may provide a long term benefit to the system that could mean less fertiliser is required in crop under an organic amendment regime.
   

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.

Nufarm are currently developing a new controlled release formulation of Triflualin.

• The 2016 trial results looking at cultural control techniques for barley grass largely confirmed the 2015 findings.
• Increasing barley seeding rate in the presence of barley grass can provide substantial benefits to both yield and reduced weed seed carry-over. This applies particularly to competitive varieties such as Fathom, but also to less competitive varieties such as Hindmarsh.
• In contrast, doubling the seeding rate of wheat had no beneficial effect on yield or weed carry-over.
• Doubling the district practice seeding rate in barley substantially reduced the competitive effect of barley grass to the stage where crop yields were similar to those plots where herbicide was applied.

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 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.

There are two main forms of ‘precision agriculture’: guidance, to improve accuracy, decrease overlapping, improve efficiency etc (the benefits are well understood for guidance); and variable rate agriculture. Variable rate agriculture

• Crop seeding rate and perennial row spacing both influence grain yield of pasture crops.
• Lifting seeding rate of pasture crops might compensate for poorer establishment and, in turn, help to reduce any grain yield penalty.  For this experiment and assuming lupin seed is $300/t, lifting seeding rate by 50 kg/ha ($15) helped to avert a 26% yield penalty and proved to be $165/ha more profitable overall.
• Where growers do not own a disc machine but have invested in precision guidance technology, with forward planning, it is feasible to use a tined machine to sow crops into perennial pastures without damaging the perennial base.

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.

• Pasture cropping is an option for KI producers wishing to maximise grazing/cropping options.
• If you want to remove kikuyu from a paddock use roundup – if you want to pasture crop use other herbicides.
• Excellent lamb growth recorded 250g/hd/day.
• Producers now have a range of herbicide options toast will enable them to establish a crop without killing the kikuyu.

• Wet seasonal conditions hindered establishment of some crop species
• Seasonal conditions were ideal for pasture re-growth
• 3 cuts were taken at Conmurra throughout the season

• August pasture termination may produce water and nitrogen benefits for the following crop, compared to leaving the pasture to grow, but these may be neutralised by dry summers and other limitations in an average growing season.
• Termination timing is only as important as you abiliy to capitalise on the benefits with either livestock (extra pasture growth) or crop (extra water and nitrogen).

• Plant tests at the end of July showed that crop N and P uptake were significantly increased where 300 kg/ha Super Phos had been previously applied.
• Super Phos applied to pasture increased crop yield from 3.0 t/ha to 3.9 t/ha but responses to more than 100 kg/ha Super Phos were not significant. There were no significant responses to potash, lime, manipulation or to Intake in Furrow.
• Grain proteins were about 11 %, hectare litre weights 78 kg/hl and screenings 2 % (data not presented).
• 100 kg/ha Super Phos increased protein yield by 77 kg/ha (or grain N recovery by about 14 kg N/ha). 
• This is the equivalent to about 40kg fertiliser N/ha (assuming a nitrogen use efficiency of 35%).
• The value of the crop response to pasture topdressing alone was big enough to more than offset the cost of 100 kg/ha Super Phos applied over the previous three years.

• 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.

• The most important results from this work, being those obtained from the wheat stage of the system, will need to be collected for several more years in order to develop substantial findings.

• Benefits from inoculating peas far outweigh cost.
• Higher rates of inoculants may be worth considering.
• Granular inoculant yielded better than peat but not statistically significant.
• Lime pellets must use seed coat grade lime.

• The yield of the trial was not collected by the weigh trailer, but I felt the wheat on the fallow trial was at least 20-30% higher yielding than the wheat on wheat.
• The wheat on the fallow trial was higher in stature, looked a lot healthier and larger grain size.
• Looking overall at yield wheat on wheat would have been 0.9 to 1 t/ha and the fallow would have been approx. 1.2 to 1.3 t/ha.

Although the results were inconclusive at the Tottington site, the group believes that use of the triple pack program in normal years is likely to improve perennial pasture establishment in this drier northern region. It could also be relevant in other areas, where run down low fertility paddocks have a low legume content and have become dominated by onion and silver grass.

Further cost benefit analysis is warranted for the Triple Pack system before it is widely promoted to producers. PPS were unable to conduct a cost benefit analysis at Tottington due to the extreme seasonal conditions affecting results.

• Atriplex and Rhagodia species fared best in these experiments, producing the hightest biomass on offer to sheep, plant survival rate and health scores.
• Four species showed poor adaptation to the environment at Walpeup and produced little edible biomass, namely Atriplex semibaccata, Convolvulus remotus, Cullen australasicum and Medicago strasseri.
• Results from this experiment and others across the nation have led to establishment of a new site a Manangatang that demonstrates the most promising spcies for the Mallee region's poorest soils.

• First wheat following canola yielded between 3.65 and 5.35t/ha depending on row spacing, plant population and nitrogen application.
• A narrow row spacing of 22.5cm produced higher dry matter (DM), grain yields and water use efficiency than a wider row spacing of 37.5cm.
• Higher grain yields were associated with plant populations of 150-165 plants/m2.
• Wide row spacing reduced grain yields by and average of 6.5% and DM by 15% compared with narrow row spacing. 

• 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. 

For a summary of key messages and results see the attached trial report.

• 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.  

• Canola trials during 2012 had high plant populations, which may have created atypical crop canopy structures in relation to different row spacings.
• In four canola datasets generated from 2009 – 2012 at Coreen, New South Wales and Bungeet, Victoria the influence of row spacing on yield has been inconsistent.
• During 2012, the narrow row spacing (22.5cm) produced higher yields and a higher harvest index (HI) than wider row spacing, however this has not been the case in previous years. 

• With 537mm growing season rainfall (April- mid-November) wheat yields followig faba beans were 2.2t/ha higher than those experienced in 2009.
• The yield reduction moving from a narrow row spacing (22.5cm) to wide (37cm) was 12% (0.64t/ha), compared with 16% (0.49t/ha) in 2009.

For a summary of key messages and results see the attached trial report.

• With 570mm growing season rainfall (GSR) 2010 wheat yeilds were more than double those experiences during 2009 in the same rotation position (wheat after canola).
• Yield drop-off associated with the wide row spacing (37.5cm) was almost identical to 2009 results, with a 12% yield reduction compared with the narrow row spacing.

• 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. 

For a summary of key messages and results see the attached trial report.

• In second wheat after faba beans, moving from a narrow row spacing of 22.5cm to 30cm and 37.5cm row spacings reduced yield by 4% and 10% respectively.  This compares with respective yield reductions of 12% and 14% in the fi rst wheat trial grown in the same paddock at the same time.
• The narrow row spacing (22.5cm) produced greater biomass than the wider row spacing but had a relatively poor harvest index (26%) compared with other row spacings in this trial.
• There was no difference in crop establishment or yield due to drill opener (tine versus disc), however plant establishment was superior with the narrow row compared with the wider spacings tested.
   

• Gauntlet wheat sown as the second wheat crop after canola yielded between 3.84–4.44t/ha with 232mm of growing season rainfall (Apr-Oct) and an estimated 118mm of stored water at sowing (total 350mm).
• Moving from a narrow row spacing (22.5cm) to 30cm and 37.5cm row spacings reduced yield by 13% and 11% respectively in the 2012 season.  In 2011, moving from a 22.5cm spacing to 30cm and 37.5cm spacings reduced yield by 4% and 10% respectively for the second wheat trial grown in the same paddock.
• It was estimated that the narrow row spacing (22.5cm) resulted in better water use efficiency (WUE) than the widest spacing (37.5cm), despite having a lower harvest index (44% vs 47%) than the widest rows.  

• Wheat on wheat (following canola) yielded 4.91t/ha, almost 1t/ha less than the neighbouring first wheat trial after canola, which yielded 5.84t/ha.
• There was no yield drop-off associated with wider row spacings (30cm and 337.5cm) in this wheat-on-wheat situation.

• Plant establishment at a 22.5cm row spacing was signifi cantly superior to 30cm, which in turn was signifi cantly higher than 37.5cm. The disc drill opener gave better establishment than the tine at the narrow (22.5cm) row spacing but not at the wider row spacing. 
• Advantages with the narrow row spacing were seen early in the season in terms of plant population, dry matter (DM) and tiller production. These advantages did not translate to signifi cantly higher yield in this rotation position. This result was identical to the results of the 2010 trial when wheat on wheat yields showed a similar, but not signifi cant, trend for narrow row spacing (22.5cm) to be better than wide row spacing (37.5cm). 

• Banding low rates of biochar can reduce cropping input costs and improve profi tability.  
• Biochar can improve the effi cacy of fertiliser but should not be regarded as a fertiliser in its own right.
• More is not better. A rate of around 35kg/ha of biochar plus a modest rate of DAP produced the best economic outcome for all rates of DAP used in the trial (0, 50 and 100kg/ha).