• In 2013 there was no evidence of changes in soil condition or organic carbon associated with the application of compost at up to 3 t/ha in 2012. Potential changes in soil organic carbon and other soil properties will be determined in February 2014.
• This trial will be continued in 2014 to assess changes in soil condition and future production.

• In 2013 there was no evidence of changes in soil condition or organic carbon associated with the application of compost at up to 3 t/ha in 2012.
• Potential changes in soil organic carbon and other soil properties will be determined in February 2014.

• Results from experimentation undertaken in southern NSW in 2011 and 2012, have demonstrated that crop sequences which include a brassica or legume break crops can be as profitable as, and in many instances more profitable than, continuous wheat.
• Canola was consistently the most profitable break crop option. However, the rotational benefits of canola were usually restricted to just the first subsequent wheat crop whereas additional wheat yields can occur for 2 years after a legume.
• Growing pulses for grain maximises profit, particularly in favourable seasons, but compromises grass weed control and (depending upon species) reduces N available to subsequent crops compared to brown manuring.
• Growing pulses for hay was found to be profitable across a range of season types, achieves excellent grass weed control and provides greater N inputs and higher carry-over of soil water than when the same crop is grown for grain.
• Growing pules for brown manure loses money in the year they are grown, but achieves excellent grass weed control, high N inputs, residual carry-over of soil water, provides more ground cover, and requires less labour than when grown for hay or grain.

The Gross Returns (Income less Input Costs) for this demonstration using 2016 wheat prices for APW1, APW2 and ASW1 indicate that farmer practice (control) had the highest return of $443.61/ha (Figure 7 and Table 3). The second highest return was the spaded treatment at $442.11/ha.

All the treatments made a profit during 2016 between $303.13/ha to $443.61/ha. For a season such as 2016 where there was sufficient rainfall for plant establishment and growth, wetters may not be required at seeding which would reduce input costs.

Results generated using an average wheat price of $250/t over all treatments indicates that farmer practice (control) would still have the highest return of $465.81/ha, whilst the ploughed treatment would have the second highest return of $462.52/ha (Figure 8 and Table 4). All treatments would make a profit over $353.11/ha.

Over both scenarios the Gross Return ranking trend remained similar, with the soil amelioration treatments bringing a greater return than the wetters and DBS knife point at depth.  There is a larger $/h return difference between the two wetter treatments when comparing the 2016 wheat prices due to the grade of the grain (Table 2); $52.55/ha for 2016 wheat price and $22.67/ha for average $250 price.

It would be interesting to see how all plots at this site perform under a range of seasonal conditions. A multi year Gross Returns analysis could indicate a change in the $/ha return ranking trend in seasons where wetters have a greater influence on plant establishment. This analysis may also present significant return on investment for the soil amelioration treatments in the second and third year crops.

The wheat following brown manure contained higher numbers of the listed weeds. However, numbers were not critically high in the wheat treatment.

Overall the fallow without tillage contained higher weed densities than all the other treatments with fleabane at 0.57 plants/m2. The brown manure peas had very low levels of marsh mallow and milk thistle. Both speed tilled treatments were very clean.

Study Conclusions

Potential nitrogen contributions are assumed to be 40% of the total nitrogen contribution, assessed from the dry weight and nitrogen content (N% tissue) of the green manure crops measured at anthesis. Legume crops provided the most potential nitrogen of all treatments, due to high tissue nitrogen and moderate to high biomass production. Oats had the highest biomass but were low in tissue nitrogen and potential nitrogen benefits were therefore negligible. Any benefits from this type of crop, would be largely associated with the contribution of organic carbon to the soil. Emergence of both canola and mustard was poor, whilst the lathyrus and vetch competed poorly with weeds due to slow initial growth.

The percentage of undecomposed material remaining on the soil surface at seeding in 1999, varied from approximately 35% for oats down to 10% for lathyrus. The general pattern was that the crops with higher tissue nitrogen content broke down quicker. This indicates the microbial degradation of legume crops is likely to be faster than for brassica or cereal crops.

Differences in water infiltration observed may indicate the potential for treatments to increase the initial sorptivity of soil (ability for more rapid entry of rainfall) and decrease the flow rate through the soil (effectively increasing moisture retention). This may allow earlier sowing after summer rains, increased moisture availability during the growing season and potentially longer availability under dry finishing conditions. These results are variable and subject to trial/operator error. Further evaluation of these attributes is required prior to evaluation of renovation techniques.

The high cost of seeding and maintenance of the green manure crop, can significantly influence the gains or losses experienced over this three year period. It may be most economic, to green manure legume crops in seasons with low potential returns (poor yield potential or price).  The cost of harvesting a lupin crop for example may prove less beneficial than using it as a green manure to improve wheat yield and quality, where prices are depressed or where disease/season has reduced yield potential. Strategic use of green manure crops as a tool in integrated weed management or potential productivity gains through addressing specific problems may result in little or no short term economic gain where employed in better performing paddocks and must be viewed as a long term strategy to overcome yield constraints. However, strategic use of these techniques for poor performing paddocks, or paddock that would have otherwise been ‘rested’, are likely to result in economic responses, particularly where using low cost crops or pasture has been employed as there is no requirement to recover the cost of foregone yield – only those associated with growing a crop and the implementation of techniques.

Data supports the hypothesis that a green manuring:wheat:wheat rotation, may be as profitable as a legume:wheat:wheat rotation using either a field pea or Lathyrus crop. Given this assessment does not include any additional benefits that may be gained from green or brown manuring in terms of additional weed control and potential improvement of soil characteristics such as the addition of organic material, improved soil structure and longer term productivity gains, these techniques are likely to prove both economical and sustainable by providing additional benefits that may be observed in lower herbicide costs through better weed management, improved soil health and a more flexible farming system.

Over all four trials both Sakura treatments maintained a positive $ROI/ha with Sakura + trifluralin ($78.50) slightly ahead on average $ROI/ha to the standalone Sakura ($73.48)

Sakura 118 g/ha recorded a $55.08 increase in $ROI/ha over Boxer Gold across the four trials. Boxer Gold $ROI was generally in line with that of the prosulfocarb treatments in three of the sites, except from Waddy Forest where prosulfocarb 2.5 L/ha recorded a higher yield. Why this occurred is not clear as results were cross checked back with the contractor to ensure there was not a transcription error.

Trifluralin, due to its poor weed control, especially at Cunderdin, returned a slight positive $ROI/ha ($7.20) across the four trials.

All four sites to some extent were affected by frost which may have affected yield outcomes.

Getting weed control right is the key to ensuring the longevity of any herbicide but it also allows the crop it’s best possible chance of achieving its yield potential. Using a program of effective knockdowns and a product with a long residual activity like Sakura can deliver higher yields and returns across a variety of soil types and locations as seen across the four trials conducted during the 2016 season.

• All three seeders have resulted in successful establishment of sub-tropical grasses at the paddock scale.  This reinforces that successful establishment can be achieved with a range of seeding machinery providing the basic principles are followed: i.e. furrow sowing, press wheels, precise shallow seeding together with wide row spacing.
• The disc seeder appeared to have the least soil disturbance, with less loose soil on the soil surface after seeding, but had slightly more sand infill.  This may be due to steep side walls and a relatively narrow furrow, while the seeders with tynes created larger – wider furrows, so sand moving into the furrow was spread over a wider base.  The Case-International combine with a single point had the lowest sand infill.
• The disc seeder resulted in the highest establishment of panic grass, but in late October many of these plants were still small seedlings and subsequently many died over summer.  As number of plants, size and health of plants need to be taken into account, the disc machine may not provide an overall advantage as the proportion of healthy plants was much less. Visually, the Case-International combine appeared to produce a thicker stand; this was most likely due to the higher number of medium to large sized plants when compared to the other machines. 
• The knockdown did not completely kill the brome grass which subsequently recovered and competed with the emerging perennial grass seedlings in early spring.  Combined with dry conditions in October (5 mm) the perennial grass seedlings were struggling in late October.  More favorable seasonal conditions in November and December enabled the grasses to establish.  The scalping points on the John Shearer were able to reduce the impact of brome grass more successfully than the other seeders.
• Persistence will be measured over late summer until the break of the season.  This machinery demonstration trial will be the focus of an extension video which features the producers describing the modifications to their seeders.

• This trial demonstrates that a good establishment result is possible using a range of different seeding configurations, provided the key steps to establishment are followed.
• These factors include:
  • scalping of non-wetting sand and weeds away from drill runs;
  • row spacing of 50-60 cm;
  • sowing into furrows to harvest rainfall (especially important in dry springs); minimizing furrow collapse;
  • ensuring sowing depth is 5-10 mm; and - using press wheels for good soil contact with seed.

• Treatments were a single application of 10 kg/ha of Zn as zinc sulfate monohydrate (ZSM) (35% Zn) in 1996 or 4 applications of 1.25kg/ha or 2.5 kg/ha Zn as Incitec.
• Granulock ST-Z (10 %N, 19.5 % P, 2.5% Zn) between 1996 and 1999. Soil samples were collected at the commencement of the experiment, after the first application and post-harvest from the fourth crop.
• Samples were analysed for DTPA extractable Zn.
• The percentage of soil extractable Zn available from applied Zn after 4 cereal crops was about 12 % for the single application of 10 kg/ha Zn as ZSM, 22% for multiple applications of 1.25 kg/ha Zn and 20 % for 2.5 kg/ha Zn as STZ.
• It would appear that provided there is no compromise in crop productivity, a multiple low rate strategy of Zn fertiliser addition may be more effective in building available soil Zn concentration than a single higher rate.

Overall, early growth was a function of a number of constraints. In the fully retained stubble plots plant establishment was poor due to large straw windrows creating major problems at sowing and mice damage. In surface stubble treatments lower soil temperatures and higher populations of vulpia resulted in reduced plant vigour. Where stubble was fully retained this effect was less than when most stubble was removed through cutting and baling.

• Plant emergence was greatest in the offest disc treatment and lowest in the mouldboard plough treatments. Depth of sowing is critical and difficult to control on soil ameliorated soils.

• KING ROCK fell in a hole early, ran up quickly and often looked very heat and moisture stressed.
• LONGREACH COBRA did not handle a dry year. It did not appear robust or durable in a dry warm season.
• CORACK and MACE handled drought stress well.
• CALINGIRI and MAGENTA looked the most durable and robust all year.
• CALINGIRI again proved very adaptable.

Average yields ranged from 2.1 to 2.5t/ha.

Soil amendments applied in 2004 did not significantly improve wheat yields in 2005.

The high fertiliser regime yielded significantly higher than the district practice regime and the low fertiliser regime.

• Conserving summer rain is one of the most effective ways of improving crop yield.
• Summer weeds have the biggest impact on how much summer rain is stored and made available to crops.
• The presence of stubble has never been shown to have a large positive effect on the storage of summer rain in southern Australia, but it might lengthen the sowing window after the break and improve establishment.

• Weeds have the biggest impact on summer water storage.
• Over the last two summers, the method of weed control had little effect on moisture storage
• Even under adequate growing season rainfall, weed control is necessary because weeds tie up and/or prevent significant amounts of nitrogen mineralizing, which cost 0.5t/ha of the canola yield.

Controlling summer weeds conserved both water and nitrogen and doubled wheat yields in 2011 on both sand and clay soil types. Retaining or removing stubble has only minor effects on wheat yield. Complete control of summer weeds pays, and there is no excuse for weedy paddocks during summer in the Wimmera and Mallee!

• Conserving summer rain is one of the most effective ways of improving crop yield.
• Summer weeds have the biggest impact on how much summer rain is stored and made available to crops.
• The presence of stubble has never been shown to have a large positive effect on the storage of summer rain in southern Australia, but it might lengthen the sowing window after the break and improve establishment.

• Conserving summer rain is one of the most effective ways of improving crop yield.
• Summer weeds have the biggest impact on how much summer rain is stored and made available to crops.
• The presence of stubble has never been shown to have a large positive effect on the storage of summer rain in southern Australia, but it might lengthen the sowing window after the break and improve establishment.

• Conserving summer rain is one of the most effective ways of improving crop yield.
• Summer weeds have the biggest impact on how much summer rain is stored and made available to crops.
• The presence of stubble has never been shown to have a large positive effect on the storage of summer rain in southern Australia, but it might lengthen the sowing window after the break and improve establishment.

• Conserving summer rain is one of the most effective ways of improving crop yield.
• Summer weeds have the biggest impact on how much summer rain is stored and made available to crops.
• The presence of stubble has never been shown to have a large positive effect on the storage of summer rain in southern Australia, but it might lengthen the sowing window after the break and improve establishment.

• Conserving summer rain is one of the most effective ways of improving crop yield.
• Summer weeds have the biggest impact on how much summer rain is stored and made available to crops.
• The presence of stubble has never been shown to have a large positive effect on the storage of summer rain in southern Australia, but it might lengthen the sowing window after the break and improve establishment.

• Overall imposing a fallow allowed for a small amount of extra water to be stored in the soil and a small amount of extra nitrogen. As a result there was a small yield gain of 0.2 t/ha in 2012. 
• In this trial the fallow treatment was planted then sprayed out in August to replicate what is known as an ‘opportunistic’ fallow compared to a ‘strategic’ fallow where no crop is planted for 18 months. 18 month fallows would have different results to the ones reported here.
• Other benefits of fallow that were not recorded in this trial but could have contributed to the yield gain are improved weed control, disease breaks and opportunity for early sowing. 

• This is the second season in which this trial has been run and the fallow has yielded higher than continuous cropping in both 2011 (0.4 t/ha) and 2012 (0.2 t/ha). Other research indicates that fallows produce yield benefits in dry seasons which are not the case in the crop in 2011, which received 231mm for the growing season. The yield difference in 2011 was therefore more likely to have been the result of extra nitrogen in the soil, or weed or disease control rather than soil water benefits, however, these were not measured.
• Farm economics need to be carefully considered before implementing a fallow, the opportunity cost of not producing a crop needs to be weighed up, and benefits of yield, extra N, weed control and disease breaks carefully factored into the decision. 
• In 2012 the yield benefit from fallow was 0.2 t/ha and likely to be due to extra nitrogen and water being present in the soil. However, this is an unreplicated demonstration and thus it is hard to tell whether yield differences are the result of fallow or random variation in the paddock. 

• Western Flat (Ramseys) soil modification work. Site was established in 2009. After 2 seasons, the area that organic matter was spaded into is performing well.
• Wolseley (Matthews’); alternative fertiliser demonstration; no differences were found between soil biology after a 12 month period.
• Lochaber Ag Bureau (Clothiers); Peries Wightman subsoil manuring project
• Dairy sites with Dairy SA based around the Mt Gambier region
• Coonalpyn Ag Bureau Soil pit days
• Coonawarra Grape Growers – historical composting trial sites revisited
• Sherwood – soil modifications in conjunction with additional carbon project

• 10 new soil demonstration and trials to be established in the south east over the next 2 years.
• Opportunities for farmers to access expert soil advice and information through a series of community meetings, workshops and field days. 

• Continuous wheat can be successfully grown.
• Stubble has been burnt to reduce the incidence of yellow leaf spot in the following crop.
• In most years the crop has been direct drilled.
• Disease levels are still low and the crop is checked at flowering every year for root diseases.
• Continuous wheat has been relativley low risk - after 7 years it has not failed (except for the drought year in 2002).
• Thus far there is no problem with grass weeds or soil borne diseases.

• Soil and solution culture studies were conducted to examine the relative contribution of different mechanisms of zinc efficiency at the whole plant level in bread and durum wheat during early vegetative stage.
• While there are a number of mechanisms of zinc efficiency, zinc uptake appears to be the most important mechanism • Seed zinc remobilisation and root to shoot translocation do not appear to be important to zinc efficiency.
• Visual scores of zinc deficiency were significantly correlated with zinc efficiency, and they provide a useful criterion for an initial screen of zinc efficiency.
• This study was based on vegetative growth and the conclusions need to be verified under field conditions.
• The percentage deviation technique provided a straight forward means of comparing the relative effects of different components of zinc efficiency and the method could be extended to studies that use grain yield as the measure of zinc efficiency.

• Grazing stubble with sheep speeds up N cycling and reduces N tie-up by the stubble. When yield is N limited, this can increase grain yield and quality.
• Over the seven year experiment, grazing and retaining stubble has been the most profitable treatment, with an annual Gross Income 172 higher than un-grazed, stubble retain (assuming a grazing value of the stubble) or $55 higher if no grazing value assumed.
• Over the seven years, there was on average a 0.5 t/ha reduction in wheat grain yield in the 2nd wheat crop where stubble was retained and not burnt – mostly related to N tie-up.

The trial establishment was variable early due to some non-wetting soil and the crop was sown too deeply due to furrow fill from significant rain after sowing. Early crop vigour as a result was low with blackleg further reducing plant establishment; this coupled with high levels of Vegetable beetle damage also reduced the evenness of the plots.

According to the DAFWA sporacle model spore maturity occurred on approximately the 22nd May which meant this trial was at very high risk of significant disease risk as emergence coincided with high spore levels being released from last year’s stubble.

• A Predicta B sample taken from the site indicated a medium risk of rhizoctonia although patches did not express during the season.
• Early establishment across the site was severely impacted by non-wetting affected all plots across the trial with the worst of it commencing around plot 215 and increasing in severity throughout replicate 3.  Early dry conditions further staggered the crop emergence.
• Good rains through late July and into early August ensured the crop was growing well albeit patchy across the trial with high levels of disease present at both the Z31 and Z39 applications. Only 48.9 mm of rain fell from the second Z39 application to the end of October reducing the benefits to yield of the different fungicide treatments.
•  Increasing variability in the trial due to the sub-soil issues from plot 215 into replicate 3 was a significant factor. Yield data should be treated with caution due to the variability of the site with disease control is the most accurate assessment of treatment efficacy.

• Observations in N.S.W., Victoria and Western Australia clearly show that tap rooted crops have excellent straight tap roots when grown on beds when compared to flat paddocks. 
• These initial considerations suggest narrow raised beds may offer a better overall soil water exploration throughout different depths of the profile and a better depth of rooting by crops. 
   

• Vetch production in a very tough season was little affected by trafficking imposed in 2015.
• After three years of crop production, low levels of trafficking have had little impact on grain yield on a Minnipa soil, multiple trafficking on wet soil (in 2015) increased grain yields in the second and third crops.
• Ripping conducted in 2015 lifted the soil substantially but has not benefited production in any of the following three crops.

• Multiple machinery pass trafficking decreased crop yields for at least four years on a Loxton deep sand.
• Single pass machinery trafficking did not result in yield decreases at Loxton and rarely at any of the other trafficking soil types in this project.
• Most soils in the south-eastern Australian Low rainfall zone are not likely to remediate from compaction naturally.

This work has demonstrated that N2O emissions from trafficked soil were consistently and significantly greater (by an average factor of 2.2) than those from non-trafficked soil. At the same time, soil CH4 consumption was significantly increased in the CTF beds compared to random-trafficked or permanent traffic lanes, although overall CH4 fluxes were small. Permanent traffic lanes normally represent only 10%–15% of field area on controlled traffic farms, compared with ∼50% or more trafficked area on non-controlled traffic farms. Thus, the results indicate that adoption of controlled traffic should reduce soil emissions of C2O-e by 30%–50%, and this effect would be greater if N fertiliser could be excluded from permanent traffic lanes.  The reduction in emissions also indicates that less N has been lost by denitrification, an effect which might be in the range of 3 – 20 kg/ha.

The work has demonstrated that CTF will reduce the GHG emissions from grain production, in addition to providing economic and other environmental benefits.
 

• A single application of Uragan (bromacil) plus paraquat in May gave complete control of all weeds at all sites over both rates. However, the additional expense, soil erosion risk and irsk to remnant vegetation need to be considered.

Results 4 & 5 years after the initial Cu application on a gravelly soil near Wandering indicate responses to copper but clover persisted without Cu applied.

Zinc applied as a basal.

The Cu concentration in October 1967 was low [possbily due to sampling time].

Design is a incomplete factorial and Cu residual measured as a run down rather than comparisons to new or current applicationa of Cu

• Copper concentrations in tissue on sandy soils declined with the age of the plant, with indications of copper deficiency for older plants.
• Patches of crop with partially empty heads were observed while the rest of the head was still green.
• Suggested that EDTA extractable copper might give indication of likely copper deficiency in sandy soils.
• Deficiency can be overcome by applying copper fertilisers to soil (long term solution) or a foliar copper spray (short term solution).

• Main areas at risk from Inglewood and Yelbaron in the south to Tara and Condamine in the north.
• Occurs on grey or grey brown clays or sandy clays which carried belah and brigalow in their native state.
• Variance in triticale varieties in responsiveness to copper sulphate.
• When copper fertiliser was placed in dry soil it was unable to be taken up by plants and grain yield, but not straw production, was severely compromised.

• 21 field trials across Southern Wimmera.
• At 18 trials the treatments included 2 kg ha of copper spray-applied to soil and incorporated at sowing; foliar applied copper (75 g Cu/ha) at late tillering; and 150 g Cu/ha at booting; a nil treatment.
• The other 3 trials investigated correction of previously diagnosed Cu deficiency.
• One of the most responsive sites in 1984 was reinvestigated in 1985 using similar treatments on an area which had not previously received copper.
• Grain yield and micronutrient of YEBS for Cu were measured.In 1984 grain yield response to applied copper was 0146 t ha-1 for wheat grown on the Yellow Duplex soils and 1.32 t ha for the Deep Sand site.
• The Red Duplex and Non-Friable Clay soils were not Cu deficient.
• In 1985 responses on yellow duplex soils (important cropping soils in region) were much smaller: attributed to fact it was a drier year than 1984 (no waterlogging).
• In 1984, leaf Cu concentration was initially sufficient but fell below the critical minimum after the onset of waterlogging and remained low until the soil dried out.

The program demonstrated that:
• At some sites where copper deficiency was historically assumed, no response to any form of copper application was observed. Copper response is likely to vary by site and season.
• Yield loss caused by copper deficiency can be devastating to wheat yield.
• Soil and tissue testing can be useful in helping to detect low levels, but are not always definitive. Copper response appears to be dependent on other complex interactions such as soil moisture, yield potential and other constraints (N fertility etc.) and thus soil/tissue tests alone are not a definitive guide to future responses.
• Foliar applications performed better than in-furrow liquids.
• Chelate and sulphate products performed equally well when applied as foliar applications.
• Timing did not appear to be critical, with a wide band of opportunity from mid-tiller to early head emergence providing similar results

Soil DTPA was 0.27 mg/kg soil.

Grain yield increase by 32 % for both granular and fluid applied Cu.  About 1.3 kg Cu /ha was required for maximum grain yield of 3.2 t/ha.

Foliar application reached 85% of the maximum yield when applied at flag leaf before flowering; earlier application at first node was effective but only reached about 75% of the maximum.  

At this site seed coating had a small effect on germination of seedlings and was insufficient Cu for wheat seedling to recover from Cu deficiency.

Flag leaf Cu concentrations were 1.3 mg Cu/kg and grain Cu concentration from nil Cu treatments were 1.3  mg/kg

Soil DTPA was 0.32 mg/kg soil.

Grain yield increased by 2 % for both granular and fluid applied Cu.  About 1.5 kg Cu /ha was required for maximum grain yield of 3.32 t/ha.

Foliar application reached 97% of the maximum grain yield when applied at flag leaf before flowering; earlier application at first node was effective but only reached about 95% of the maximum.  GY

At this site seed coating had no effect on germination of seedlings..

Flag leaf Cu concentrations were 1.5 mg Cu/kg and grain Cu concentration from nil Cu treatments were 1.4  mg/kg

• The addition of copper and zinc fertiliser applied in 1952.

• Cu  applied in 1959 increased grain yield of wheat. 

• Copper was applied as Cu ore equivalent to about 5 kg Cu sul/ha.

• THe response of wheat  to Cu in 1959 was not annticipated .

• As there was very large responses to Cu in 1959, doubts arose as to whether Cu was originally applied. However, clover grew well in 1952 suggestion Cu had been applied, along with the plain supper Zinc 

• Conclusion a second application of Cu is required to the soil type.

• Wheat, rye and triticale were grown in three Australian soils at low and high levels of trace elements.
•  All basal nutrients were supplied in copper and zinc added at 4 mg/pot.
• Addition of copper alone greatly increased pollen viability.
• Addition of zinc alone either decreased pollen viability or had no effect.
• The results confirm the tolerance of rye to extremes of soil pH and to both copper and zinc deficiency.
• In all environments adding zinc alone aggravated copper deficiency.
• Genotypic differences in copper zinc interaction showed up most strongly in soils of pH 7 and 9.

• Zinc applied as a 0.5% zinc sulphate spray completely corrected symptoms of zinc deficiency in field trials.
• Increasing the concentration of zinc sulphate (0.5, 1 and 1.5%) or applying twice did not affect plant response.
• To be fully effective sprays had to be applied two weeks after emergence.
• Soil applications of 125 kg/ha zinc sulphate were fully effective but not lesser rates.

• Cover cropping did not improve cotton yields in this experiment.
• High stubble loads from spraying out the cover crop after the cereals reached growth stage Z39 negatively affected established cotton plant numbers and consequently lint yield.
• Cover crops terminated at growth stage Z39 had no yield penalty, but stored more soil water than the fallow treatment.

• Ornithopus sativus (French serradella) was capable of yielding as much as Trifolium subterraneum (subterranean clover) with 30% less phosphorus (P).
• Ornithopus compressus (yellow serradella) required 30% less P than T. subterraneum to produce the maximum yield, however its maximum yield was often lower than that of T. subterraneum

• Grain yields were increased 20-30% by the soil or foliar application of zinc, provided that phosphorus was also supplied.
• Critical zinc concentrations determined in the glasshouse and field were the same, being 19-24 mg/kg throughout the life of the crop and 13-15 mg/kg zinc in grain.

• Crop establishment was not improved by on-row seeding or by increasing seeding rate in 2016.
• Higher seeding rate increased early dry matter but this effect declined during the growing season.
• In 2016 row placement or seeding rate did not affect grain yield or grain quality.
• Sowing on-row may be an advantage on non-wetting soils with low moisture at seeding.

Neither crop establishment, grain yield nor quality were changed by on-row seeding or by increased seeding rate in 2017, similar to results in 2016.

Crop establishment in the non-wetting soil was poor in 2017.

In 2015, with low moisture at seeding, improved crop establishment from on-row seeding in the non-wetting soil increased crop competition and lowered brome grass weed seed set.

• Deeper sowing at 3-4 cm achieved better early dry matter and increased grain yield in a later sowing.
• Frost damage may have lowered yield with early sowing, but inter-row placement at TOS1 had the highest yield.
• TOS 3 placement in row achieved better early plant growth and higher grain yield.
• Later sowing reduced brome grass numbers, and the size of the panicles, so it substantially lowered returns to the seed bank.

• Crop establishment increased with on row sowing. Stubble from the previous season helps soil moisture infiltrate into non-wetting sands and into a position closer to the seed.
• Initial germination of brome grass weeds was higher with inter row sowing.
• Late brome grass weed numbers was also greatest with inter row sowing. Sowing on row may also increase crop and weed competition as will a higher seeding rate.

Over 3 years of crop production (2009-2011) applying replacement phosphorus (P) rates have been the most economic.

• A replacement P strategy produced similar yields to 10 and 20 kg/ha P rates in 2010.
• The trial indicated an economic benefit in increasing P rates up to 20 kg/ha on a deep sandy loam in 2010.

• Legume crops consistently increased pre-sowing soil nitrogen in the year following the break.
• Two-year break phases that included a brown manure vetch phase have generally resulted in the highest pre sowing soil nitrogen levels in the subsequent wheat crops.
• One and two-year break phases reduce Rhizoctonia soil inoculum, however levels increase significantly following the first cereal crop.
• Two-year break treatments generally reduced brome grass populations in the cereal phase, however all rotations relied on Clearfield herbicides for brome grass control by the second wheat crop following the break.
• The benefits from extra soil water following some break phases in this trial have been variable and small.

When sub-soil water is present, growing high value canola and legume break crops can be profitable in the Mallee.

Where brome grass seed bank populations are high, break crop sequences of longer than two years are necessary to decrease numbers, and keep them down.

The application of CLF herbicide chemistry is effective in reducing brome grass populations, but herbicide resistance will develop quickly if they are used repeatedly in the same paddock.

• The choice of legume species and management were found to influence the amount of nitrogen fixed by both crop and pasture legumes byaffecting either legume reliance upon N2 fixation for growth or changes in dry matter accumulation.
• Medium to high soil mineral N concentrations at sowing appeared to suppress N2 fixation by field pea more than lupins or faba beans.
• Pulse legumes grown for grain generally result in lower net inputs of fixed N.
• Available soil N following either legume crops or pastures can represent an additional 40 to 90kg N/ha in the 1st year.
• The increased N uptake by the 1st wheat crop grown after legumes was equivalent to 27-40% of N in the previous year's legum residues.

• Wheat sown after break crops produced up to 1 t/ha more than wheat after wheat
• The greatest benefit of the break crop was produced at the earliest sowing
• Safflower produced the break crop effect but produced low wheat yields, small grain but high protein due to drying out the soil profile.

• Break crops can be just as profitable as wheat crops.
• Antas sub-clover (for hay production) as the break crop was the most profitable option.
• Beans were the most effective at fixing nitrogen, averaging 13 kgN/tDM produced.

• Break crops can be just as profitable as wheat crops
• Antas sub-clover (for hay production) as the break crop was the most profitable option
• Beans were the most effective at fixing nitrogen, averaging 13 kgN/tDM produced

• There was limited varietal response from crop-topping in 2011. This may be due to below  average rainfall during late October and early November, the rapid finish on a shallow soil and the relatively late sowing date, suppressing some yield potential of untreated plots.

• The disc and the early sown no-till tillage systems produced the highest grain yields, 1.41t/ha and 1.36t/ha respectively.
• The early sown no-till system had the lowest protein and the highest screenings.
• The disc tillage treatment had the least available soil nitrogen in autumn.

• All the legumes sown - peas, lupins, sub clover and faba beans - were equal in terms of their nitrogen-fixing capabilities, reflecting the importance of having well nodulated legumes.
• The average amount of N fixed by the legumes was calculated at approx. 86kg/ha.
• In year 2, this residual N gave rise to a approx. 1 t/ha canola yield advantage.
• In yera 3, no differences in residual nitrogen from legumes were measured.
• Linseed extracted more moisture, from a greater depth, than the faba beans in the same year and all subsequent crops - canola and oats.
• The linseed was able to dry the soil profile in a decile 10 year (812mm rainfall). This is a potential solution for farmers wanting to dry out their soil profile.
• Two years after growing linseed, soil moisture levels were even.

Effective control of summer weeds before cropping can increase both grain yield and quality. The key to increased yield potential lies in additional sub-soil moisture available to the crop during the subsequent growing season. Summer weeds also deplete mineralised N reserves. Provided there are no limitations preventing crop roots from accessing the subsoil, the additional soil moisture can be seen in higher grain yields and generally grain protein and test weight.

There are no significant differences in yields between the control and the CFF plots on a wodjil soil type.

• Have established at what level the bucket is full
• Have a better understanding of where it becomes empty
• Have increased our confidence in utilising these tools
• In-crop nitrogen sampling has been a vital tool in assessing the effectiveness of the modelling

Key findings:

• Nitrogen (N) decision making requires a good understanding of background soil and plant science, and soil test interpretation.
• Training for new agronomists needs to be a priority issue.
• Senior NSW agronomists identified crop yield expectation as guided by soil moisture at sowing (or at the time of N decision making) as the most important determinant of N fertiliser requirement.
• Further research is needed to increase the understanding of how management practices affect potentially large gaseous N losses. 
• Changing from legume pasture-crop sequences to continuous cropping in many central and southern areas of New South Wales is posing new questions for managing N supply. The absence of N-fixation by pasture legumes is seen as a substantial loss of N-buffering capacity.
• Despite most advisers choosing soil testing as a key approach for determining N fertiliser required, many of their clients had a lower confidence in soil testing, citing ‘high perceived variability in soil nitrate results in the lead up to sowing’.
• Conclusions and Recommendations Senior advisers highlighted the importance of quality training in N decision-making, understanding the background soil and plant science involved, and soil test interpretation for the next generation of agronomists, with training courses including representation from highly experienced local agronomists.
• The understanding of gaseous N losses requires further research, development and extension to the grains industry. Recent field research in the north was limited in scope and produced challenging outcomes that can potentially lead to large practice changes in when and how N fertiliser is applied. Further research and development work is warranted to answer more of the practical questions growers and advisers are asking in regards to losses associated with various alternative practices.

• The northern results on N loss pathways are less relevant to advisers in the central and southern regions where N application timing, soil type and climatic differences are generally quite different from the dominant medium-heavy clays of the north. New N loss research is recommended for the lighter textured soils in regards to the potential for N volatilization losses from surface N application of various products. Economic outcomes from the various strategies being practiced are also needed. Nitrogen loss research should focus less on expensive slow-release products and more on optimising results from urea, the cheapest N source.

• Research into better soil water measurement was seen as a priority area, especially given the importance all advisers place on knowing this when making expensive N-fertiliser decisions for a coming cropping season. Zonal management within paddocks is not possible with single site characterisations, so atypical areas of paddocks are over or under-fertilised.

• The very early application of N fertiliser ahead of a winter cropping season is well established, but what is not known is how well the subsoil N may be protected or at risk from denitrification in flooding events. Also, better knowledge on specific N use within the profile during the cropping season will help growers to know when late-applied N is likely to be inaccessible to crop use.

• Nitrogen mineralisation was highlighted by agronomists from all three regions as an area for greater understanding with regards to the differences caused by climatic conditions, especially rainfall. They also require better understanding of the N produced from both native organic matter and recent legume pasture residues.

• There are a number of good decision support tools available currently, with several advisers suggesting that combining the best points of each into one package, even one available as an app, would be highly useful, particularly one with good grower-friendly reports.

• Many farmers have low confidence in soil testing.  This may be related to a range of factors from poor sampling strategies, to poor sample handling, to poor service from laboratory analysts, to insufficient sample numbers or poor interpretation of the results. It is seen as an expensive option for many, with some advisers looking for quicker and cheaper means of estimating soil mineral N.

• Variety-specific N management packages were seen by some senior advisers as key areas for continued research funding, as results from some new varieties have been quite different in terms of N uptake and protein outcomes.

• Making nitrogen (N) management decisions requires an understanding of soil and plant science, and soil test interpretation.
• Training new agronomists is a priority.
• Senior NSW agronomists identified crop yield expectation as guided by soil moisture at sowing (or at the time of N decision making) as the most important determinant of N fertiliser requirement.
• Further research will increase the understanding of how management practices affect potentially large gaseous N losses.
• Changing from legume pasture-crop sequences to continuous cropping in many central and southern areas of New South Wales is posing new questions for managing N supply. Less frequent pasture legume phases with their N-fixation benefits to the soil is seen as a substantial loss of N-buffering capacity.
• Despite most advisers choosing soil testing as a key approach for determining N fertiliser required, many of their clients had a lower confidence in soil testing, citing ‘high perceived variability in soil nitrate results in the lead up to sowing’.

• Soil pH results after liming and tillage treatments were applied was found to be quite variable and more sampling needs to be done before pH results can be quoted. Soil loosening indicates that only the deep tillage techniques were likely to incorporate lime into the deeper 20-30 cm acidic layer.
• This trial highlights the importance of measuring subsoil pH levels and applying sufficient rates of lime to prevent and correct subsoil acidification. Where tillage treatments are used to incorporate lime it is important to understand to what depth lime will be incorporated and which subsoil layers need correction. It is intended to monitor this trial for the next few years to further assess the benefits of correcting subsoil acidification. Yield response to lime incorporation can increase over time as the untreated soil continues to acidify further and as lime has more opportunity to react and neutralize the acidity that is present.

• Removal of soil compaction and subsurface acidity via deep banding lime to 30cm resulted in 18% yield increase over the untreated control.
• Despite the gross margin of the deep banded lime treatment being $35/ha less than the control in 2005, the benefits of deep ripping and lime application will still be realised in future years.

• Removal of soil compaction via deep ripping to 30cm resulted in  44% yield increase which equated to a gross margin of $38/ha more than the untreated control
• Addition of lime did not significantly improve yield in 2006, however, it is possible that a response will be gained in future years as subsurface acidity is present in the soil profile.

• Removal of soil compaction via deep ripping to 30cm resulted in  44% yield increase which equated to a gross margin of $38/ha more than the untreated control
• Addition of lime did not significantly improve yield in 2006, however, it is possible that a response will be gained in future years as subsurface acidity is present in the soil profile.

• Removal of soil compaction via deep ripping to 30cm resulted in  44% yield increase which equated to a gross margin of $38/ha more than the untreated control
• Addition of lime did not significantly improve yield in 2006, however, it is possible that a response will be gained in future years as subsurface acidity is present in the soil profile.

This work has demonstrated that it is possible to incorporate lime into seams in the soil profiel which can increase the soil pH and decrease the levels of toxic aluminium.

• Yield increases from deep ripping ranged from 220 to 750 kg/ha.
• Deep ripping demonstrations provide a tool to assess possible yield gains across various soil types.
• Replicated trials are needed to validate the yield increases seen at this demonstration site.

• Deep ripping dry sand was more effective with two passes (or shallow leading tines); less cloddy.
• Yield benefits of 410 kg/ha (18%) from deep ripping were mainly due to better head fill. Better head fill was probably due to better cooling of the crop in hot weather due to better supply of moisture.
• Extra moisture seemed to be from rain which infiltrated deeper in the ripped soil to avoid more evaporative loss than the unripped soil.
• A controlled traffic system will better protect the investment in deep ripping and extend the benefits. Deep ripping costs will also be reduced when the permanent tramlines are left unripped; seeding can also be easier with better flotation on permanent tramlines.

 

• Deep ripping enabled the crop to access about an extra 40kg of soil N/ha.
• The crop was as responsive to Flexi-N after deep ripping.
• There was no yield penalty from delaying Flexi-N application until the end of tillering. Deep ripping and Flexi-N were very profitable at this site.  

• Deep ripping did not affect depth to free water in 2018 or 2019; however these were decile 2 and decile 1 growing seasons at Kendenup West.
• Yield data was limited; however deep ripping may have produced a cultivation effect that slightly increased yield.
• Deep ripping is unlikely to be a reliable management option for waterlogging in forest gravel soil.

• Rip to below your compacted layer
• Ripping to 60cm reduced soil strength, and this effect continued into the second year after ripping
• Wheat yield response to the 60cm rip treatment paid for deep ripping in the first year
• Important to understand potential yield benefits of ripping before you rip

Deep ripping provided a 446 kg/ha wheat yield increase in 2017.

The penetrometer measurements show that the nil treatment at both sites had a harder soil profile in the upper 20 cm at Hannafords (clay loam) and down to 35 cm at Jacobs. The reason the Nil treatment at the site of Hannafords shows lower resistance at depth is because this zone was waterlogged (water perched on the clay layer), showing that the ripping and spading have relieved some of the waterlogging. 

The penetrometer measurements show that the nil treatment at both sites had a harder soil profile in the upper 20 cm at Hannafords (clay loam) and down to 35 cm at Jacobs. The reason the Nil treatment at the site of Hannafords shows lower resistance at depth is because this zone was waterlogged (water perched on the clay layer), showing that the ripping and spading have relieved some of the waterlogging.

Sub-soil compaction, caused primarily by the unmanaged movement of heavy machinery, is having a negative effect on grain yield and quality across the Geraldton Port Zone (as well other port zones in WA).  Compaction limits plant root growth, reduces plant available water capacity (PAWC) and in turn limits yield potential.

The profitability of a crop is dependent on the crop maximising the use of rainfall received and the PAWC of the soil is critical to this. This applies to all rainfall zones. Climate change however, has influenced the number of dry periods occurring during the growing season, so it’s more important than ever for crop roots to be able to explore the soil profile to the fullest possible extent.

Growers report that some soils on their property continue to underperform despite their fertiliser and system management strategy matching their soil type. The introduction of deeper deep-rippers to the region (550 – 700mm) has shown encouraging results, prompting growers to question current strategies and investigate the rippers as options for soil improvement.

In 2016 four growers within a 100km of each other currently employing deeper ripping strategies were asked to compare the performance of ‘deeper’ deep ripping (550-700mm) to standard deep ripping (250 – 350mm) and no ripping.  A full soil, plant tissue and grain yield analysis was performed at each site to gather information on the base site parameters and breakdown of how each soil responded to the treatments.

There was an increasing response to deeper ripping associated with a decline in rainfall at the sites (about 100mm variance across sites). To achieve the best return on investment growers are recommended to identify the sub soil constraints in their paddock before choosing the right tillage machine to alleviate them.

• Ripping below the hard pan (greater than 500mm) in pale sands, yellow sands and yellow loams in wheat or canola increases yield.
• Soil moisture probes show ripping deeper (below 500mm) allows more plant roots to access moisture deeper in the profile for longer in the season. Water infiltration also increase with depth of ripping.
• Leaving a firm even seed bed after deeper ripping is important to reduce seeding establishment issues.
• A negative yield response to deeper ripping in lupins on yellow sand was measured at Binnu in 2016.
• Crop yield response to ripping does vary depending on seasonal conditions and crop type therefore the economics of ripping must be considered over multiple seasons and timing of ripping in the rotation.

• Deep ripping to 500-600mm in coarse textured sandy soils increased yield by 21-66% compared to 6-24% with ripping to 300mm in wheat and canola in 2016 and 2017 in the Geraldton port zone.
• There was only a small yield response to ripping the red loam in 2016 and no difference in 2017.
• Soil moisture measurements and visual observations of plant root growth indicated deeper ripping allowed the plant roots to access more water from deeper down the soil profile. This is particularly beneficial in sandy soils that have a low plant available water capacity(PAWC) per 10cm down the profile therefore roots need access deeper into the soil profile to gain the same amount of water as heavier textured soils that have a higher PAWC per 10cm.
• Economic analysis found the higher cost of deeper ripping gave a positive return on investment up to $5/ha for every dollar invested at 3 sandy sites but not on the red loam where the return on investment was negative with a return of $0.63/Ha for every dollar invested. On the sand at Ogilvie there was a yield penalty in lupins in 2016, resulting in a negative return on investment which could not be recouped in the following dry season of 2017.
• If ripping below 400mm, consideration must be given to crop selection in year one (lupins are higher risk); leaving an even seed bed post ripping to reduce bogging and plant establishment issues; and managing weeds as due to poor competition and better access to water and nutrients can increase the weed burden as these factors can have a negative impact on yield reducing the return on investment.

Soils in the Wharminda and Stokes area of Eyre Peninsula were mapped and areas of micronutrient deficiency established by applying micronutrients (copper, zinc, manganese, iron, boron and molybdenum) in 24 factorial field experiments.

Fertiliser applications were made at the 1-2 leaf , tillering and booting stages.

• Grain yields were increased by copper application at 11 of the 24 sites.
• Zinc application increased yield at one site, manganese at one, iron at two and molybdenum at two sites, no increased due to boron application were recorded.
• Copper deficiency occurred in deep siliceous sands, calcareous sands, solodized solonetz and solodic soils with light brown sand at Wharminda.
• Zinc and manganese deficiencies were mostly confined to soils with a high carbonate content near the surface.
• Copper in the grain was a better indicator of deficiency than copper in the soil.
• Grain yield responses to copper application were indicated by grain copper of <2.5 ppm.

June 13th sown Gairdner produced yields in the range of 4.86 – 5.69 t/ha following canola stubble. With high soil nitrogen reserves (203 kg/ha N, 0‐90cm) recorded at sowing, there was a small but significant response to applied nitrogen (0.21 t/ha at 50 kg/ha N & 0.23 t/ha at 100 kg/ha N). There was a significant advantage to nitrogen timed during stem elongation (GS31‐33) over nitrogen applied in the seedbed.

Late sown Mitre (July 4) produced yields in the range of 0.6 – 2.16 t/ha following Canola stubble. With soil nitrogen reserves of approximately 30kg/ha N (0-10cm) recorded pre sowing, applied nitrogen was detrimental in this trial, with 50 kg/ha N reducing yield by 0.09t/ha and 100kg/ha N reducing yield by 0.23 t/ha. These figures disguise more detrimental yield reductions with seedbed nitrogen applications and no effect from stem elongation timings applied at GS31-39.

Late sown Mitre (July 4) produced yields in the range of 0.6 – 2.16 t/ha following Canola stubble. With soil nitrogen reserves of approximately 30kg/ha N (0-10cm) recorded pre sowing, applied nitrogen was detrimental in this trial, with 50 kg/ha N reducing yield by 0.09t/ha and 100kg/ha N reducing yield by 0.23 t/ha. These figures disguise more detrimental yield reductions with seedbed nitrogen applications and no effect from stem elongation timings applied at GS31-39.

• The wild radish population was consistent and of high density (303 /m2) across the site. Spray coverage was affected due to the high weed density and with 65% of the wild radish 4 leaf or larger across the site at application shading was also an influence.
• This trial was applied immediately after rainfall so soil moisture was good but the weeds had just endured a fortnight of frosts with very dry conditions and were still highly stressed.
• Coverage issues and the seasonal conditions prior to application coupled with ongoing dry and stressed conditions following application have contributed to lower than expected wild radish control from all treatments in this trial.

 

The PA Concept Farm gave growers the opportunity to see first hand the difficulties and successes of implementing new and innovative cropping techniques involving PA (Precision Agriculture) and CTF (Controlled Traffic Farming). Although final yields were not of importance due to the nature of the site, various observations throughout the year demonstrated to visitors some of the things to watch for when adopting these tools and practices. The fact that yields were not altered indicate the importance of maintaining dedicated wheel marks all season, and the implications of adding machinery such as that used to bale hay. The site also demonstrated that without amelioration, soil improvement due to reduced compaction can take a number of years to manifest into greater yields. 

Weed burdens at the site highlighted the importance of ensuring control in wheel marks, whilst indicating that wider row‐spacing does not necessarily mean increased weeds. The difficulties of keeping seeding equipment tracking straight when precision sowing were also encountered, making for a good discussion with site visitors about the various techniques that can be used to overcome this problem.

Costs of guidance were compared for the site, with $3/ha for line marking using a contractor with autosteer, $190/ha for a contractor to set up a whole paddock with beds and between $20,000 and $50,000 to get one machine setup with Real Time Kinematic (RTK) autosteer including your own basestation.

A demonstration to showcase options for managing water repellent soils was established in 2017. Mace wheat was sown into sand over gravel (below 20cm) on 24 May following 209mm summer rain, with no rain in April and 14mm in May.

• One-way plough reduced subsoil compaction to 30cm depth and improved soil wettability, crop establishment and yield.
• Deep ripping reduced compaction to 30 cm depth, improved crop establishment and yield, but not soil wettability.
• Knife point sowing established and yielded better than the splitter boot when sowing on deep ripped and one-way ploughed plots.

• Broadleaved break crops increased pre sowing soil nitrogen by up to 40 kg/ha in 2014 while Rhizoctonia inoculum was also significantly reduced following these crops.
• Growing a legume break crop in 2014 increased the grain yield of the subsequent wheat crop by 0.6–0.7 t/ha.
• Wheat crops following legumes were twice as profitable than following another cereal crop in 2015.
• The profitability of paddock rotations that included legume break crops in 2014 were similar to or exceeded the profitability of the cereal intensive rotation in the same paddock.

• Broadleaved break crops increased pre sowing soil nitrogen by up to 40 kg/ha in 2014 while Rhizoctonia inoculum was also significantly reduced following these crops.
• Growing a legume break crop in 2014 increased the grain yield of the subsequent wheat crop by 0.6 – 0.7 t/ha.
• Wheat crops following legumes were twice as profitable than following another cereal crop in 2015.
• The profitability of paddock rotations that included legume break crops in 2014 were similar to or exceeded the profitability of the cereal intensive rotation in the same paddock.

• Broadleaved break crops increased pre sowing soil nitrogen by up to 40 kg/ha in 2014 while Rhizoctonia inoculum was also significantly reduced following these crops.
• Growing a legume break crop in 2014 increased the grain yield of the subsequent wheat crop by 0.6–0.7 t/ha.
• Wheat crops following legumes were twice as profitable than following another cereal crop in 2015.
• The profitability of paddock rotations that included legume break crops in 2014 were similar to or exceeded the profitability of the cereal intensive rotation in the same paddock.