• Grazing crops can offer the ability to spell pastures, however careful management needs to be practised to ensure there are no grain yield losses. Grain yield losses can very easily result in a negative profit from grazing crops.
• In this case I suggest that the paddock was grazed heavily in the days leading up to removal of the paddock and this resulted in poor recovery of the crop from grazing.  In hindsight I feel that fewer yield losses would have resulted if there was more bulk left leading into stem elongation.
• On the 17th August the Grain & Graze II trial site was visited by the Northern Agri Group (NAG) field day.  During the day we had over 100 growers discuss the pros and cons of grazing crops.  Both Don Nairn and I addressed the field day and had good feedback about the system.

• Grazing treatment had no influence on pasture sward composition when averaged over seasons.
• Grazing, rather than the type of grazing management, increased soil carbon under native pastures.
• Soil under cell-grazed pastures had a significantly greater carbon stock to 0.30 m compared with ungrazed pastures (32.9 t C/ha vs 25.6 t C/ha), however, there was no difference between cell and tactically grazed (29.5 t C/ha) pastures.

• Grazing livestock can compact surface soil and reduce infiltration rates, but their biggest impact on fallow efficiency is through stubble removal.
• Stubble improves summer fallow efficiency primarily by increasing infiltration; it slows but does not stop evaporation, and this is only beneficial where rainfall events occur close together or if it aids crop establishment.
• Despite high rainfall during the 2009-10 fallow period at Condobolin, there was little response in soil water storage to the grazing and stubble treatments.
• Wheat yield in 2010 was reduced by very heavy grazing but not by moderate (more typical) grazing.

The main impacts of climate change by 2030 on grazing livestock enterprises is likely to be shorter  growing seasons, greater variability in pasture growth, reduced pasture quality, less available pasture, reduced wool quality and increased variability in farm gross margins. Possible adaptations to alleviate
some of these impacts are;

• Minimising the need for supplementary feed by reviewing lambing and calving times, age at first joining, stocking rates and sale times,
• Increase flexibility in systems by varying sale times/rules, confinement feeding, movement, more animal trading (core breeding), agistment, matching feed demand to pasture production, and
• Improved pasture utilisation by grazing management.

Winter wheat has to potential to produce high grain and forage returns. Early grazing should be no later than GS30 in order to maximise final grain yield. Early grazing of winter wheat can reduce final stubble volumes and increase harvest index. Ideally for best forage production, winter wheat should be planted in March if possible.

• Response of lentils to herbicide treatments varied with seasonal conditions, method of herbicide incorporation, stubble coverage, soil texture and fertility.
• Treatments that showed high plant damage generally incurred high yield losses, however low levels of chlorosulfuron plant damage still resulted in significant yield loss in some trials

Estimating what a paddock will yield allows growers to manage herbicide and fertiliser inputs during the season; forward sell grain and accurately insure their crops. This is an important tool for managing gross margins and ensuring profitability.

Estimating what a paddock will yield allows growers to manage herbicide and fertiliser inputs during the season; forward sell grain and accurately insure their crops. This is an important tool for managing gross margins and ensuring profitability.

Estimating what a paddock will yield allows growers to manage herbicide and fertiliser inputs during the season; forward sell grain and accurately insure their crops. This is an important tool for managing gross margins and ensuring profitability.

Estimating what a paddock will yield allows growers to manage herbicide and fertiliser inputs during the season; forward sell grain and accurately insure their crops. This is an important tool for managing gross margins and ensuring profitability.

Canola can be successfully grown on a cereal stubble. It is not essential to burn stubble as long as seedling emergence and establishment is not affected by the retained stubble. If the seeder does not leave a good seed bed and the harrows leave the paddock uneven with clumps of mixed up straw and soil it is better to burn the stubble.

The incidence of black leg was quite high and the fungicide treatments, Rovral and Impact in Furrow did not decrease the level of infection.

In dry years, many canola crops are short and thin. Windrowing is recommended where yield potential exceeds 1 tonne/ha and crops are tall and thick enough to sit on 25-30cm of stubble. With light crops, where windrows may be blown about by strong winds, other options are desiccation and harvest or direct heading, depending on seed moisture levels.

• Harvest weed seed collection showed barley grass is harder to capture using harvest weed seed collection techniques due to its habit of shedding seed early.
• Burning windrows decreased the number of weed seeds present in the soil seedbank at Minnipa in 2017.
• Harvest weed seed collection allows for the capture of ryegrass weed seed and cereal screenings, potentially increasing feed utilisation for stock when placed in chaff dumps or rows.

• Harvest weed seed control (HWSC) — the collection and/or destruction of weed seeds at harvest — is a non-chemical control method, which can be used to reduce the seedbank of weeds, such as annual ryegrass (Lolium rigidium).

• Techniques include mechanical weed destruction, or methods involving carting or baling chaff straight after harvest. Chaff can also be concentrated behind the header in a row, which is then left to mulch (chaff lining or decking) or concentrated in a narrow windrow behind the header and burnt (narrow windrow burning).

• A major premise of HWSC is that the targeted weed species retain a high proportion of their total seed production at crop maturity.

• There was no difference between a harvest height of 30cm and 15cm in terms of the number of weed seeds returned to the soil.

• In wheat crops with high annual ryegrass plant populations, a large percentage of the ryegrass seed matures and drops in the month before wheat harvest, limiting the effectiveness of HWSC in the Riverine Plains region. In 2017, approximately 30% of total ryegrass weed seeds were removed by the harvest process.

• HWSC could be used as one tool in a larger integrated weed management strategy.

Knowing your initial soil nitrogen levels will assist in determining if there is likely to be a benefit of including nitrogen and other nutrients for humification when incorporating stubble. If initial soil nitrogen levels (0-60cms) are adequate i.e. above 70kg N/ha in the high rainfall zone, and above 50 kg N/ha in the medium rainfall zone, then the addition of nitrogen may not provide immediate responses – depending on the stubble nutrient levels.

Soil health is not a static issue. Soil is the foundation of our agricultural systems. Collating existing knowledge and building a framework for visual, tactile and oral learning based on the needs of the ‘customer’, in this case farmers and advisors, is supporting more informed decisions and a greater capacity to manage soils for a healthy future.

• Healthy Soils workshops are delivering knowledge, skills, and tools to better manage soils for improved soil health
• Care must be taken with soil sampling, transport and laboratory procedures for accurate test results
• Management significantly influences soil biology through various practices such as controlling what quality and quantity of organic matter is incorporated into the soil through crop and rotation choice, the utilisation of additives such as pesticides and herbicides, and the intensity and type of tillage employed.

There were no significant differences between the yield of either treatments. However the district practice treatment had a significantly higher thousand grain weight to the biological treatmeant. 

Common heliotrope (Heliotropium europaeum L.) is an opportunistic annual weed that grows in ‘disturbed’ areas (i.e. areas of bare or sparsely vegetated soil) following summer rain in regions with a Mediterranean climate (hot dry summers, cool wet winters). In its natural habitat, which includes most of the rim of the Mediterranean Sea, farming practices result in there being few disturbed areas during summer, hence common heliotrope is not such a problem. However, in the dry-land cropping belt of southern Australia, the wholesale clearing of native vegetation and the endemic broad acre agricultural practices leave vast areas of fallow, hayed-off pasture and sparse stubble over summer; all of which are ecologically speaking ‘disturbed’, and hence fantastic habitat for common heliotrope.

• In 2015 the drier start to the season and low soil moisture resulted in lower herbicide efficacy and less chemical damage than expected.
• In different stubble management systems the activity and resulting weed control of specific herbicides will be influenced by the solubility index (movement through the soil profile with rainfall events) of that herbicide. Soil texture and soil chemical properties can affect chemical movement and availability in the soil profile.
• Herbicide performance will vary seasonally due to soil moisture levels, rainfall pattern post application, timing of weed germination, position and number of weed seeds in the profile, etc. Understanding how the various herbicides work can reduce the likelihood of failures.
• Herbicides are only one tool for weed control – always adopt an integrated weed control package that includes non-chemical control, and where possible, consecutive seasons of total weed control.
• Consider the whole farming system when making chemical decisions as the impact may last for several seasons (eg. effects on medic germination and medic seed bank).

• Herbicides which may be influenced by high stubble loads include trifluralin, triallate, pyroxasulfone, prosulfocarb and metalochor products. If grass weeds are an issue in paddocks with high stubble loads (greater than 50% stubble cover), removal of some stubble may maximize the herbicide activity and grass weed control.
• In-crop germination patterns are later for barley grass than for other grass weeds in MAC paddocks, which is limiting early control with pre-emergence herbicides.
• If you expect most of your grass weeds to emerge straight after sowing maybe 2 L/ha trifluralin (plus an added herbicide depending on cost and risk factors such as seasonal conditions, soil type, rotation etc.) is the best value for your system.
• If you have a later germinating population, and aim to reduce the seed bank, you may be better investing in some of the more expensive herbicide mixes even though they may cost more in the first season.

Dry seeding conditions and lack of rainfall at the start of the 2017 season resulted in challenging conditions for both establishing crops and weed control.

Stubble residues reduced plant establishment and weed numbers; standing stubble in dry conditions had higher wheat germination than chained stubble.

April dry sowing had lower wheat numbers than later sowings, which reduced grass weed competition during the season. Grass weed numbers were also higher and set more seed in the April sowing.

No pre-emergent herbicide provided total barley grass weed control and keeping the weed seed bank low through other methods is important.

Under the production regimes of upper EP, stubble management is unlikely to impact negatively on performance of pre-emergence herbicides targeting grass weed control, providing adequate water rates and best practice application techniques are used.

• No significant difference in ryegrass control was found between plots treated with any of the three pre-emergent herbicides tested.
• Though not statistically significant, the trial demonstrated a trend of increased herbicide efficacy with increasing herbicide carrier volume.

• Winter Graze n Grain Hybrids provide huge yields and multiple cropping and grazing opportunities.
• Hyola® late Spring Super Hi-Biomass Hybrids show very high yield potential in the HRZ with Hyola 725RT and Hyola 600RR topping their respective herbicide technology groups.
• Triazine Hybrids show similar performances and gross returns to the best Clearfield Hybrids and much higher Gross returns $/ha than OP TT varieties especially Hyola 650TT and Hyola 559TT.
• RT® dual herbicide tolerant Hybrids show their $/ha value and as a critical new competitive IWM management tool for all canola growers.
   

Experiments were conducted in a commercial lentil crop (2006) in a paddock considered representative of the southern Mallee region of Victoria (McCellands Jil Jil East). The study identified that seasonal variations in the spatial pattern for grain yield were explained principally by differences in the ‘effective plant available water’ (ePAW) rather than differences in nitrogen supply. ePAW was considered to be related to both the textural properties of the surface soil (eg. small rainfall events at the season break are more effective in coarser textured soils than in clay soils) and the presence of physio-chemical in the subsoil, which can limit crop access to stored water.

• Applying phosphorus to a soil with low P reserves when establishing a medic pasture boosts shoot and root dry matter, improves root health and improves N fixation.
• The addition of urea at seeding can reduce nodulation in medic pastures.
• Residues of the herbicide Logran can severely stunt medic growth.
• Applying a full label rate of Agritone 750 (late) decreases pasture production and N fixation in actively growing pastures.
• Any management practice that reduces medic biomass will reduce N fixation, such as the late application of certain herbicides, eg Agritone 750.
• In a dry growing season when medic plants are already moisture stressed, herbicides will have little impact on medic production and N fixation.
• Regardless of seasonal conditions, the management of newly established medic pastures with regard to herbicides and nutrition, appears to have no impact on the yield and protein levels of the wheat crop in the following year.

• VBHT805 is an inidazolinone tolerant barley variety in the final stages of evaluation and commercialisation.
• VBHT805 could be a useful tool for managing Group B soil residual herbicide carryover for improved grass weed control in intensive cereal rotations.

• The trial was sown into dry soil on the 11th May. This trial was indicative of many lupin crops within the West Midlands region in 2010, with establishment and weed control issues. Establishment was inconsistent across the trial site with seasonal conditions, non-wetting soil and rhizoctonia root rot contributing to uneven plant numbers and poor growth within some plots. Herbicide management of weeds, particularly ryegrass, was less effective than expected, resulting in high weed burdens, especially in plots with poor lupin establishment.
• Anthracnose was introduced into plots 4 weeks after sowing but warm dry weather following introduction of infection and long dry spells during the growing season reduced disease development.
• Disease assessments at crop maturity indicated that despite high levels of inoculum being introduced only low levels of disease were present within the trial and differences between varieties were not statistically significant. Approximately 10% of the moderately susceptible Jenabillup plants suffered stem infection, the resistant variety Tanjil and resistant breeding lines had between 2-4% of plants with stem infection. Pod infection levels were low across the trial due to dry weather during podding.
• Due to uneven establishment, variable soil moisture, root disease and weed burden, individual plot yields varied from 0.5 t/ha to 2 t/ha across the site (average 1.4 t/ha), however neither variety nor anthracnose infection significantly affected yield.
• In seasons with good rainfall, anthracnose can be a yield constraint for lupin production in the high-medium rainfall regions of the northern agricultural region (particularly in areas with abundant blue lupins); the anthracnose resistance in current advanced breeding lines will reduce disease development and yield loss.

1. Barley and wheat crops led to increases in P. neglectus, while mungbeans, wheat and chickpea led to increases in P. thornei.
2. The non-host summer crops (cotton, maize, mungbean and sorghum) provided the greatest reduction in crown rot inoculum while most non-host winter crops had virtually no impact.
3. There was little impact from most species on common root rot levels with wheat the worst crop option, while common root rot declined under the moderately resistant barley variety CompassP.

Having an indication of the stubble load present at harvest in cereals and canola (based on grain yield harvested) will help with future decisions around harvest management and management of stubble loads during the fallow period.

A late sown winter wheat Marombi and experimental wheat 10.10.3 were grazed at three different times and compared to the ungrazed crop. Drymatter production available for grazing up to GS 30/31 was 1.48 t/ha for Marombi and 1.89 t/ha for 10.10.3. Early grazing had minimal or no impact on grain yield. Grazing in the early to mid vegetative stage increased grain yield of 10.10.3 by 0.36 t/ha or 5 %. However there was a yield reduction (0.48 t/ha or 8%) by grazing the Marombi. Given the limited number of samples taken, the variation in yield may not be different from the no grazing treatment. The change in stubble mass was less than anticipated, with a decline of up to 13%.

• There was a 0.17 t/ha yield advantage in the 2014 season due to removing or cultivating the previous season’s stubble, possibly due to extra nitrogen being available to the crop during the growing season.
• There was a 0.08 t/ha yield advantage at MAC this season by inter row cropping rather than placing the seed on row.
• There were no differences in either barley or ryegrass numbers at the start of the cropping season or in crop.

• There were no differences in wheat yield at Minnipa in response to stubble architecture, seeding position and nitrogen treatments in 2015.
• In 2015 plant establishment was reduced with cultivation and the addition of nitrogen at seeding compared to standing stubble cut low at harvest. The extra nitrogen applied at seeding also reduced the early dry matter.
• Removing and cutting stubble low decreased the Yellow Leaf Spot disease incidence and snail numbers compared to high cut stubble.
• Stubble management and seeding position had little effect on grass weed numbers.
• Overall at Minnipa, stubble management and seeding position have not impacted highly on crop production, weeds, disease and pests over two years with relatively high stubble loads in low rainfall farming systems.

• Barley sown into standing stubble yielded higher (between 0.15-0.33 t/ha) than cultivated or removed stubble in 2016.
• Standing stubble cut low (15-17 cm) resulted in the highest level of stubble being maintained into the following season.
• Maintaining standing stubbles may be the best option for yield and stubble carry over, but adequate nitrogen must be maintained.
• In 2014 and 2015 stubble management and seeding position did not impact strongly on weeds, disease or pests with relatively high stubble loads in a low rainfall farming system at Minnipa.

Standing stubble cut low (15-17 cm) resulted in the highest level of stubble being maintained into the following season.

Stubble management and seeding position had little effect on grass weeds.

Snail numbers were higher in standing stubble cut high (30 cm) and stubble removed had the lowest numbers.

Stubbles can be estimated using 1.3-2.8 times the grain yield, but it may underestimate the stubble in an average season following a good year, or after a very poor season.

In many low rainfall farming systems livestock are still a very important part of the farming system and the level of stubble carryover is reduced after grazing.

Stubble management and seeding position have not impacted greatly on crop production, weeds, disease and pests over three years with relatively high stubble loads for low rainfall farming systems.

• Our results from the first year of the study show that the method used to manage soil water repellence had little impact on soil nutrient supply with the exception of phosphorus. The lack of grain yield response to applied P in the mouldboard and spading treatments suggest that soil phosphorus is more available in these soils, though is not clear whether this is due to the removal of the non-wetting constraint or mineralisation following tillage.
• The lower grain yield and harvest index in the spading treatment suggests that there was less soil water available late in the growing season. Further research is required to determine how these management practices, in particular inversion and rotary spading, changes fertiliser advice. The results of this work will be used to develop guidelines on if or how nutrition should be managed for crops sown on soils treated for water repellence.

• Concentrated chaff distribution had no significant impacts on nutrient stratification either horizontally or vertically across the landscape at three sites.
• Chicken litter applications appear to complement traditional chemical fertiliser applications by increasing P availability.
• All nutrients assessed were well above established critical levels and there was a tendency for all nutrients to be concentrated at the surface (0-5 cm) regardless of the known differences in mobility between N, P, K and S.

• Paraquat Treatments provided 100% control of all sizes of onion weed.
• Ally treatments (metsulfuron) were slower than paraquat, however provided 100% control.
• Double knocks improved the speed of burn off and control.
• Glyphosate does not provide complete control of onion weed and recovery can occur.
• Glyphosate mixed with Pyresta or Starane Advanced showed reduced glyphosate efficacy.
• Glyphosate mixed with Valor and Sharpen showed no increase in control compared to glyphosate applied alone on all sizes of onion weed.
• Local seeding machines successfully established canola into a heavy barley stubble and there was no benefit in pre-sowing cultivation or burning.

• Native grasses have been established on numerous properties, however the project has highlighted difficulties with sowing light fluffy seeds.
• Wallaby Grass established well at several sites, however the dry summers have drastically reduced populations.
• The dry springs have not been suitable for the establishment of Windmill Grass and rain in the middle of summer does not appear to favour establishment

The 2002 drought may have major implications for potential weed problems during the 2003 season, including management in fallows, pastures and crops. However, there is very little published information on the impact of drought on weed population dynamics. There is some information on the impact of weather (rainfall and temperature) on effectiveness of weed control methods. The 1982 and 1994 droughts provide some guidance on the consequences of a major drought on subsequent weed problems. The most likely impact of the drought on weeds is the incursion of new weed problems into districts via fodder, grain and seed.

• Fathom barley was more competitive than Hindmarsh barley, bread wheat and durum.
• Increasing seeding rate and seed bed utilisation improved crop weed competition (by up to 60%) without a yield penalty or quality downgrading.
• Tjilkuri and Mace sown at 300 seeds/m2 with a spreader boot achieved similar ARG suppression as Fathom barley sown at 150 seeds/m2 .
• Pre-emergent herbicide application offered the best control of ARG in this trial across all varieties and agronomic management factors. 
• Non chemical strategies can significantly enhance crop’s competitive ability with weeds and should be integrated with herbicide use.

Yield variability across the 22 focus paddocks in the project was moderate to very high. Yield variation needs to be managed to minimise the significant economic losses experienced in low performing parts of a paddock. We found very good correlations between soil EM38 maps, satellite imagery of crop vigour and crop yield at harvest. Utilising our knowledge of how the crops grew this season together with the precision farming tools available we will develop management plans in each of the focus paddocks to improve water use, yield and economic return.

• EM38 surveys need to be calibrated through soil testing to identify areas with subsoil constraints.
• Simulated wheat yields using historical rainfall data demonstrated the effects of soil type and subsoil limitations on potential crop yields and recharge.
• Variable rate technology for fertiliser could optimise returns for paddocks with subsoil limitations.

• The paddock utilised for the trial had a significant number of effective naturalised medic rhizobia. There was no rhizobial inoculation response.
• Total annual biomass was higher in the regenerating medic plots versus sown treatments due to earlier germination and growth of naturalised medic.
• Grazing increased overall medic production.

• Essential plant growth requirements including nutrients and water are influenced by the capacity of the soil to both store and supply these elements.
• Infiltration of water into soil and the ability for soils to retain water are processes fundamentally important for soil productivity.
• Management strategies that increase the rate of water infiltration into soils are likely to improve the potential of the soil to capture larger amounts of water.
• The rate of movement through the soil profile however, may be more important for crop production in terms of influencing the ability of plants to utilise this water.
•  

While water volume and droplet size were the focus of this study there are further measures that can be taken by the spray operator to increase herbicide penetration in stubble. In a recent paper by Gordon (2017) some of the strategies highlighted were:

• Reducing spraying travel speeds can generally improve the penetration into stubble and improve the evenness of the application.
• Narrower nozzle spacings can also be of benefit, provided the spray quality and boom height are suitable. 
• Alternately, many operators have plumbed machines with nozzle spacings to match the crop row width. Where nozzles are positioned in the centre of the inter-row gap between standing stubble lines, the nozzle height may be lowered to obtain an overlap close to the base of the stubble. This may improve soil contact and reduce interception by the stubble, provided spraying speeds and wind speeds do not excessive.

(i) Baits do kill juvenile snails. (ii) Stubble and/or green plant material reduce uptake of snail bait by juvenile snails. (iii) A baiting program that is integrated with appropriate stubble and weed management at presowing is likely to optimise snail control. (iii) Calibrate your bait spreader to optimise the effectiveness of your baiting program. (iv) Perlka® did not have a significant effect on reducing snail populations in caged field trials. (v) The effectiveness of bait product and bait size differs between the pest snail species; once fully researched,future bait program recommendations will be tailored to the species being targeted.

• There was no effect of stubble retention on canola yield because it followed chickpea and there was very little, if any, stubble of chickpea.
• There was no significant effect of gypsum application on the yield of both canola and chickpea.

Climate variability or climate change? Whatever the situation we face we need to be prepared to respond quickly to temperature and rainfall extremes with better in-crop management decisions.

Climate variability is something we have to learn to live with, and we need to manage it better. Be prepared to learn more about the impact of increasing variability in temperature and rainfall on the bottom line of your farm.

• Electromagnetic (EM) zoning was strongly related to differences in pH at 10–30cm depth in two out of three paddocks.
• All three paddocks showed variability in chemical properties, with the EM zoning showing good separation of chemical properties between zones. This provides confidence that the zoning was suitable.
• Variability in plant growth needs to be examined ‘holistically’ rather than just focussing on one variable. While a paddock may show variation in plant available water (PAW), it may be that sodicity or subsoil acidity is the key limiter in plant performance, not water availability per se.
• Existing precision agriculture (PA) datasets, in conjunction with selected chemistry sampling, can be used to indicate relative change in PAW across paddocks, but not the actual volume of water storage.

There was a small discernable response in early season biomass to N applied at seeding at the sampling on 29 August August.

• Yield differences between soil types were less than seen in previous seasons on this paddock.
• Yield responded to an extra 25kg/ha N at sowing on the deep yellow sand over gravel and shallow gravel yielded around 2.5t/ha.

• Yield differences between soil types were less than seen in previous seasons on this paddock, although they did yield in expected order.
• Starting nitrogen levels were quite high (>100kg N/ha) due to previous crop history.
• Overall with the better responses to applied N being achieved on the better soils or where there was plenty of starting soil nitrogen, this experiment has given encouragement to the idea of managing soil types (or management zones) differentially for N.

For a discussion of results and take home messages from this trial please see the attached trial report.

Mackellar wheat was cut at early‐mid stem elongation (GS32‐33), considered too late to be grazed without affecting grain yield, to determine effects under irrigation. Dry matter production was 22% higher compared with an earlier cut at GS30‐31 (start of elongation). With adequate soil moisture the late cut plots recovered well and grain yield was only 3% lower and not significantly different to the
earlier cut plots. Extended grazing of dual purpose wheat coupled with capacity to irrigate therefore provides increased economic and management flexibility.

• EM38 successfully mapped differences in soil water properties across the paddock.
• Positive response to fertiliser in wheat on wheat and higher yielding season.
• Barley yield decreased with increasing rates of nitrogen and phosphorus fertiliser.

• EM38 successfully mapped differences in soil water properties across the paddock.
• There were no significant yield increases from increased fertiliser.
• Reducing fertiliser on heavy soils had no negative impact on yield.

The main agronomic issues to be assessed in 2012 are:

• Targeting of seeding and post seeding nitrogen applications in line with identified changes in soil water characteristics ie changes in the ‘bucket’
• Assessment of gypsum applications over soil zones identified as having variations in sodicity levels. A trial has already been implemented which will allow economic assessment for several years.
• Sound agronomic and economic phosphorus fertiliser management in line with changes in productive capacity of soil zones and responsiveness of soil types to phosphorus applications.

• No yield differences were observed between the incorporated stubble and the standing stubble plots despite differences being recorded in plant growth during the year.
• The dry spring conditions had an impact on grain yields with no significant difference observed between treatments. 

• Yield differences were observed between the incorporated stubble and standing stubble plots.
• The hot dry conditions during November had a major impact on grain yield.
• Lodging was a problem in all of the plots with the incorporated plots particularly affected.
• At this stage no significat tincrease in soil orgainic carbon was observed.

• However, the influence of seedbed N application (50kg/ha N) was evident in the crop structure scores, producing 150-200 more shoots/m2 and producing higher readings when the crop sensor Greenseeker® was passed over the trial than the GS30 stem elongation timing or the zero nitrogen controls.
• Despite a relatively low soil nitrogen reserve at sowing (43 kg/ha N 0-100cm), there was no influence of nitrogen on yield.
• In a trial subject to low levels of spot form of net blotch (SFNB), there was no response to fungicide over the untreated.

• Pre-emergent herbicides can cause crop damage. Separation of the herbicide from crop seed is essential for crop safety, which is more easily achieved in knife-point & press wheel seeding systems but considerably more difficult with low soil disturbance single discs.
• Crop stubble can intercept & bind pre-emergent herbicides, which affects crop safety & herbicide efficacy. Low solubility herbicides such as trifluralin have a tendency to bind strongly to crop residues, which reduces the potential for crop damage but also limits its ability to provide effective weed control in situations with heavy stubble load.
• Choose the right herbicide for the job – not all pre-emergent herbicides behave the same so follow label recommendations closely.

Take Home Messages

Whilst the trial didn’t go according to plan there were still some key messages that arose:

• Maximising seed-soil contact is the aim at sowing especially for the larger seeds that require more moisture to imbibe and germinate compared to small seeds.

• Unseasonably low June rainfall hindered establishment of partially sown beans due to a drying topsoil. These may have been

OK under normal June rainfall conditions.

• Hair pinning can be a serious issue when using a disc seeder especially when sowing into wet/ moist lodged stubble.

• Solutions to avoid hair pinning – sow when stubble is dry (good in theory), keep stubble standing, use sharp discs and ensure bar

has sufficient down force to cut through tough stubble.

• Analysis of wheat crops sown after rice harvest in the Murray Irrigation Ltd districts (MIL) found that increasing yields required different management depending on soil type and irrigation layout.
• Four management factors that limit winter crop yields were identified: waterlogging, late season water stress, under-fertilisation and low soil pH.
• In the MIL districts alone, increasing wheat yields after rice from the current median to the 80th percentile would result in an additional 20,000–30,000 tonnes per annum ($4–6 million at $200/t).
• If all rice areas were sown to wheat after harvest every year and 80th percentile yields achieved, an additional 128,000–138,000 tonnes of wheat would be produced ($26–$28 million at $200/t).

• This trial is a large-scale experiment, the data collected provides an indication of treatment effects and demonstrates benefits and pitfalls of adopting these subsoil acidity management methods on a large-scale. The small plot trials are more accurate and provided detailed statistical analysis of the impact of different treatments.
• Further years of research and analysis from this site and other sites will confirm these findings.

• Research funded by the GRDC- SARDI Bilateral Research Agreement.
• Focus on ‘Integrated Farming Systems in the Medium Rainfall Zone’.
• Three field components, long-term rotational trials, targeted agronomic trials and focus paddocks.

• Sow chickpea crops between standing wheat rows.
• Sow the following wheat crop directly over the row of the chickpea crop from the previous year.
• Keep wheat stubble intact and do not spread it across the soil surface.
• This will maximise yield of both chickpea and wheat crops and reduce the incidence of crown rot in the wheat phase of the rotation sequence.
   

• Insect prest pressure was generally low in Victoria and Southern NSW for 2001.
• There was no significant yield differences between the different pest control treatments, with the site mean being 4.92t/ha.
• Selective insecticides promote and encourage beneficial species which can be useful in combating harmful pest species attacking crops.

Insecticide sprays are effective in controlling crop pests, but do not always provide yield benefits.

These trials demonstrate that certain crop species and cultivars such as barley, oats and grazing wheat, can
suppress weeds effectively at standard establishment rates. This may be due to their ability to compete
effectively with weeds for valuable resources, or their potential to exhibit allelopathic effects associated either
with the crop or remaining residues following harvest.

• The seed catcher treatment reduced the ryegrass seed bank from 2007 most effectively
• Delaying sowing in 2008 from the 29th May until the 6th June decreased the ryegrass population by 55%.

• A combination of chemical and non-chemical weed control strategies can extend the life of herbicides and improve the sustainability of intensive cropping systems.
• Windrow burning, crop topping and chaff carts are options which can reduce the ryegrass seed bank without any yield penalty.
• Cutting a cereal crop for hay for one year can significantly decrease ryegrass levels in the following crop.

• Integrated weed management is the best approach for long-term control of herbicide resistant annual ryegrass.
• The most effective cultural control method trialled was mouldboard ploughing which was significantly better than stubble.burning or direct sowing into retained stubble in terms of in crop weed numbers.
• Sakura + Avadex Xtra IBS herbicide regime achieved the best control of annual ryegrass later into the season.
• Crop establishment, wheat yield and grain quality were not affected by the choice of weed control method in this trial.

• Pre-emergent weed control with Sakura reduced annual ryegrass populations by 85-97% compared to the control

• Combining Sakura pre-em with Boxer Gold at GS11 resulted in 97% weed control 180 days after sowing

• Sakura provides robust pre-em weed grass control and can be used as one element of an integrated weed management approach

• Other practices that can form part of an IWM strategy include paddock selection, cultural control, grazing, land fallowing and chemical rotation

• Continuous cropping and a reliance on pre-sowing weed control measures is not an effective way to manage herbicide resistant annual ryegrass over the long term.
• The increase in weed numbers over time can be limited by adopting an intensive and high cost herbicide strategy, but this will not deplete the seed bank.
• Increasing annual ryegrass density was associated with decreased grain yield.

• The negative effect of water repellence management at this site is at odds with other work in this project. In both years we have observed a lower grain yield in the banded wetter, mouldboard ploughing and spading treatments than in the control at this site.
• However, the average yield response to mouldboard ploughing and spading was 550 to 600 kg/ha over 28 sites.
• For further details please see the attached trial report.

In a high yielding trial (5-6 t/ha), Baudin barley gave small responses to fungicide (mean 2- 4%), compared to Gairdner which gave no response.

Despite an exceptionally dry growing season (GSR Apr – Nov 235mm) first cereal barley averaged 3.6 t/ha, with Gairdner giving a mean yield of 3.50t/ha and Baudin 3.71t/ha. As a consequence of the season, disease did not develop in this trial (irrespective of variety susceptibility), meaning that it was not possible to examine the interaction between nitrogen timing and fungicide requirement.

The later maturing feed wheat Mackellar was significantly lower yield than the earlier AH category variety Chara, with mean yields of 2.35 and 2.52 t/ha respectively. Much of this difference was due to the poor performance of Mackellar under the seedbed nitrogen application, since when compared at the later nitrogen timing alone, the mean yields were 2.55 and 2.60t/ha for Mackellar and Chara respectively. Fertilising with upfront nitrogen had less detrimental effect on yield with an early maturing variety with lower tillering capacity than it did with later maturing wheat (Mackellar) that had a longer tillering window.

In a decile 1 growing season, with no rainfall in October, barley yielded between 1-1.5 t/ha. Baudin averaged 1.38 t/ha, with the experimental low protein barley VB0229 averaging 1.31 t/ha. Both were superior to Gairdner, which as a result of poorer establishment, averaged only 1.02 t/ha.

Dry sowing resulted in the poorest weed control at seeding and as a consequence this treatment was the weediest later in the year.

• Spray-seed drift during shielded spraying damaged the lupin plants in this trial.
• Lupins yielded well when sown in rows 50cm apart.

Soil biota hold the key to sustainable crop production via impacts on processes like suppression of disease outbreaks and the cycling of essential nutrients.

• Hybrid choice and plant population had a significant impact on the yield of sorghum with irrigation. MR Buster yielded significantly higher than the other hybrids evaluated, while the higher population rates of 100,000 and 150,000 plants/ha yielded higher compared with the lower planting rates.
• The development and yield potential of the late season heads was compromised, and therefore the later developing sorghum did not take full advantage of the greater soil moisture of the intensive irrigation rate.

Conclusions

The experiment showed there are considerable productivity gains to be made by growers by selecting the right hybrid and plant population when irrigating sorghum. Irrigation management can significantly influence the growth of sorghum hybrids, affecting plant height, and grain development. Population did have an effect on yield during the trial with the higher planting populations of 100,000 & 150,000 plant/ha resulting in significantly higher yields than the 50,000 & 75,000 plants/ha. The higher plant numbers took advantage of the high plant available water from the irrigation treatments. 

In this trial, burning significantly outyielded six other stubble retention treatments at this site in 2006. Whilst grain quality had little influence on classification in the 2006 drought, the economics of burning showed more that a $100/ha Gross Margin benefit.

On average, the surface retained treatments appeared to yield marginally better across this site. There appeared to be no difference in grain quality between treatments. There appeared to be no significant levels of insect pest or predator numbers in either the assessed standing stubble or the burnt treatment at the crop early emergence stage. There was however twice as many beneficial species in the stubble retained treatment. Insects that were present included both beneficial and harmful earwigs at very low levels, spiders and carabid beetles (that were of importance). Soil water data at crop anthesis indicates that the higher yielding treatments experienced lower soil moisture levels to 60cm, reflecting a possible increase in transpiration from greater crop biomass. Plant available water in the burnt and wider row treatments was higher, but not significantly different.

• In the 2008 season, the two treatments with the poorest plant establishment counts (stubble burning and incorporation) yielded significantly more than the remainder of the standing stubble treatments.
• Incorporation yielded on average 2.4t/ha for the three seasons, 0.2t/ha  greater than standing stubble and cellulose digester, but was not a more profitable option. 
• For the duration of this project, the gross marging outputs suggested that burning was the least profiatble, with all other treatments comparable, with a $300/ha return. With this outcome in a series of dry years, farmers should use what tools they know work best for them in a profitable and sustainable manner to manag crop stubbles in the future. 

• Understanding key drivers and processes in controlling awnless barnyard grass (Echinochloa colona), feathertop Rhodes grass (Chloris virgata), fleabane (Conzya bonariensis L), windmill grass (Chloris truncata) and sowthistle (Sonchus oleraceus L).
• Investigating the impact on weed control of pupae busting and the potential impact of removing this tillage operation.
• Demonstration of integrated weed management principles, including controlling ‘escape’ weeds and the impact on seed set, to encourage industry to adopt the research outputs.
• Glyphosate resistance is emerging in cotton farming systems.