• The random survey found that button grass infests approximately 45% of cotton fields.

• The species shows a high level of physical seed dormancy.

• Seedlings of this species can survive a moderate level of water stress.

• Southern populations of this species are sensitive to saline conditions.

• Clover content in kikuyu can be increased by hard grazing of the kikiyu stand prior to the opening rains (insure RLEM are controlled, lime if soil is pHCaCl<5).
• Sowing legumes can increase legume content. If grass suppression is used, weeds may also increase unless control measures are taken.
• Legume content can be increased after the break by using a grass selective herbicide to suppress the kikiyu, if you have an adequate clover seedbank.
• If clover needs to be added, drill seed in, don't broadcast.

• Germination of half the species at each trial site was above 33 plants/m2.
• Although most of the speices achieved this good germination many of the plants have now died or are looking very water stressed.
• On visual assessment, both Rhodes species and Signal grass have experienced the highest survival rates and are looking the least water stressed.
• The grasses would benefit greatly from a summer rainfall event.

• Germination of half the species at each trial site was above 33 plants/m2.
• Although most of the speices achieved this good germination many of the plants have now died or are looking very water stressed.
• On visual assessment, both Rhodes species and Signal grass have experienced the highest survival rates and are looking the least water stressed.
• The grasses would benefit greatly from a summer rainfall event.

• Pasture cropping is a relatively new system combining livestock and crop production on the one area of land.
• Production of crop and pasture individually can be lower when grown together in a pasture cropping system compared with when either is grown alone, however the overall annual production can be higher.
• Pasture cropping systems can be managed so that annual winter crops have no direct competition from pastures while the crop is growing.
• Pasture cropping can improve year-round resource use increasing overall annual productivity compared with conventional annual cropping or pasture systems.
• Pasture cropping will be most effective in soil types that do not store soil moisture well and have some summer rain.

• Grazing pressure is greatest in winter, with volunteer pasutre providing the majority of the value.
• The stocking rates used on the improved pastures are also relatively high.
• Crop stubbles provide the majority of the grazing value in summer and autumn however they are grazed at very low stocking rates.

 

There was no significant differences in yield between the post emergent herbicides used in the trial.

Following two years of grass free medic pasture soil mineral nitrogen levels averaged 158 kg N/ha and all disease inoculum levels were low.

Cutting the medic pasture for hay lowered dry matter production and medic pod set in the following season.

An early light tickle resulted in higher weed germination and lower powdery mildew damage in spring.

Full cut tillage following two years of grass free medic resulted in the highest wheat yields while a discing prior to seeding resulted in the lowest yield.

Working medic residues in the year prior reduced the following wheat yield but grain protein was higher.

Cutting a medic pasture for hay in 2013 reduced medic productivity in 2014 and lowered wheat grain protein in 2015.

• A two year pasture break has been more beneficial in the first cereal year than a one year break, resulting in lower grass weed numbers, higher soil reserves of N and low disease levels.
• The impact of pasture management and pre-seeding tillage on grain yield and quality was greater following a medic pasture in 2015 than in 2016.

• Hay cutting in 2013 resulted in lower medic dry matter in 2017.
• Grass weed numbers were very low in 2017 due to low opening rains and poor germination.
• Two years of wheat increased Rhizoctonia, Yellow leaf spot and Pratylenchus.
• A two year pasture break was beneficial to the following cereal because of lower grass weed numbers, higher soil reserves of N and lower disease levels.

• The ability to capture barley grass seeds at harvest is limited.
• If seed can be captured and placed in windrows, windrow burning can reduce grass weeds.
• Seed capture at harvest is higher with annual ryegrass than with barley grass.
• Burnt narrow windrows sustained temperatures above 400oC for longer than 10 seconds, which is sufficient to sterilise annual ryegrass seed.
• Snail numbers were reduced with windrow burning.
• Barley grass germinates later in Minnipa Agricultural Centre cropped paddocks than in non-cropped areas.

Canola provided significant grazing value during the growing season as well as during summer.The varieties tested showed minimal yield penalties from grazing with some varieties showing a positive yield advantage from the grazing operation.Grazing canola crops were able to provide good weed control and will allow the following wheat crop to benefit from this.Grazing canola and cereal crops allows farmers to alter their stocking rate quickly and easily as they progress through the season. This practise will mean in better seasons a much smaller proportion of paddocks will need to be left for stock and more paddocks can be taken through to harvest which will result in a significant increase in farm profitability. In poor seasons there will be less paddocks taken though to harvest which will result in a reduction in grain income, higher sheep grazing losses and lower farm profitability. The overall profitability of grazing cereal crops will depend on the frequency of dry years and good years.Don Nairn finds that grazing cereal crops takes the stress out of running sheep as there is always an option for the farmer when feed runs short (ie he can simply graze another crop). Hopefully this trial gives farmers a better appreciation of where the dollars fall when crops are grazed.

These on-farm trials once again demonstrate that it is possible to graze crops in winter and maintain grain yield.  However, the frequency that yield penalties occurred (when grazing crops) increased when compared to the same set of trials in 2011.  Yield penalties (i.e. greater than 5% yield reduction) occurred in seven out of eleven (64%) trials in 2012 compared to two out of seven (29%) trials in 2011.  There are three possible reasons for this increase.  Firstly, growing season rainfall was significantly less in 2012 with most sites receiving only decile 1 or 2 rainfall.  Moisture stress may reduce the ability of crops to recover from grazing.  Secondly, a number of the 2012 trial sites were located in the low rainfall zone where the short seasons are less suited to crop grazing.  And finally, the timing and intensity of grazing may have increased the frequency of yield penalties experienced.  Four out of the eleven crops were grazed later than recommended and seven out of eleven crops were grazed heavily.  It is quite likely these three factors interact, and that a dry year or location exacerbates the negative impacts of late and/or heavy grazing.

The average amount of grazing value provided by crops was significantly less in 2012 compared to 2011 (214 vs 307 DSE grazing days per hectare).  This was mainly due to the late start and the cold and very dry July experienced in 2012.  The amount of grazing value provided by the crop is important when considering the economic implications of crop grazing.  In a year such as 2012, when grain prices were high, a small yield penalty caused by crop grazing can have a large impact on grain income per hectare.  At the current relatively low livestock prices, a lot of grazing value is needed to make up for any grain yield penalty.

• 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.

• High levels of crop safety were observed in imidazolinone tolerant lentil varieties, with no grain yield loss from any simulated residue treatments of sulfonylurea herbicides, or post-emergent applications of imidazolinone herbicides, at North Block in 2018, or Tooligie in 2019.
• High levels of crop safety were observed in the imidazolinone tolerant faba bean variety, with no grain yield loss from any simulated residue treatments of sulfonylurea herbicides, or post-emergent applications of imidazolinone herbicides, at Yeelanna in 2019.
• Access to herbicide tolerance traits will provide growers with an increased opportunity to diversify their cropping rotations and increase in-crop control options, specifically for broadleaf weed control in areas with high weed burdens.

• Chickpeas will suffer far more from being too cold and to some degree too wet than they ever will from being too hot and too dry.
• Chickpeas don’t like high levels of boron, but will handle some.
• Chickpeas have some Pratylenchus tolerance but low resistance. Do a Predicta-B test for Pratylenchus. If levels are high, you will need to find an alternative paddock.
• Chickpeas don’t like competition from weeds. Use the herbicide Balance post sowing pre-emergent. If you don’t have broad leaf weeds under control before chickpea emergence there are few herbicide options. Grass weed control is quite easy as for normal pulses, such as Targa or Select.

• Legumes are difficult, but in a heavy cropping regime they are essential in the rotation because of fertility, disease, weeds and sustainability. Trial and observation should be used to find the pulse best suited to your soils and climate.
• Sharing experience with local farmers and agronomists is very useful in this process.

Winter wheat (Rosella) sown in mid-March yielded 2.1t/ha, comparable to spring wheat sown in May (2.5t/ha). All varieties provided large quantities of excellent feed, and simulated grazing did not reduce grain yield. Sowing winter wheat in response to late summer and early autumn rain is a successful strategy for overcoming a drier April-May, but varieties adapted to the Wimmera and Mallee are needed

• Herbicide-resistant annual ryegrass (Lolium rigidum) is increasingly becoming a challenge for growers across southern Australia.
• 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.
• A major premise of HWSC is that the targeted weed species retain a high proportion of their total seed production at crop maturity.
• Where pre-emergent or in-crop herbicides have not been applied, ryegrass weeds are shedding before wheat is harvested.

Weed seed data (weeds above and below the harvest height) measurements were taken immediately prior to harvest and assessments of weed populations in the soil will be taken after autumn treatments (windrow burn and large scale burn) are applied to allow for an understanding of the effects of different treatments on the weed seed bank.
Harvest data was also collected through the yield monitor. This data is being analysed so that the additional cost of the iHSD can

Leaving straw in windrow to be burnt Weed seed data (weeds above and below the harvest height) measurements were taken
immediately prior to harvest and assessments of weed populations in the soil will be taken after autumn treatments (windrow burn and large scale burn) are applied to allow for an understanding of the effects of different treatments on the weed seed bank.
Harvest data was also collected through the yield monitor. This data is being analysed so that the additional cost of the iHSD can be established to run various economic simulations on the weed seedbank through the LUSO model and to compare the cost of the treatments. There was no significant difference in the yield across treatments or the efficiency (ha/hr). This was as expected as
the groundspeed rate was kept constant between all treatments so that the other factors.

• 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.

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.

• Care has to be taken with many residual herbicides to avoid potential damage to the following crop.
• On alkaline soils the residual effects of Glean and Ally used for summer fallowing will be severe on pulses and conventional and TT canola.
• Atrazine used for summer fallowing in dry seasons slows the growth of conventionalcanola and wheat.
• Diuron used as an over summer herbicide in this demonstration had a negative effect on conventionaland TT canola

• Moisture: Ironstone was found across some plots at depth which made any plot response to weed control difficult to measure so that there was more difference due to sub-soil constraints, rather than the individual treatments. Moisture readings were inconsistent and yields were therefore not taken.
• Weed control: Glyphosate is a very important base component when dealing with a mixture of summer weeds. The trial confirmed previous growers who experience and demonstrated summer grasses required high rates of glyphosate, at these high rates glyphosate provides excellent melon control. The Roundup Attack at 1.8 L/ha stand-alone gave the best control of grass and melons. All mixes containing Roundup Attack at 1.2 L/ha gave acceptable control of grasses and excellent control of melons when ester was added. With melons, the Triclopyr standalone was poor, but with Roundup Attack added had an additive effect, improving control significantly. Whilst no oil was used, perhaps the performance of the bottom three mixes may have given a better result with oil. Ally (metsulfuron) had an additive effect with the grasses but was antagonistic with the melons.

• 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.

• Velocity®, Precept® and Affinity® are the best options for elongating amsinckia.
• There is a wider range of effective herbicides to control amsinckia when they are small and actively growing than when they are elongating.
• Trifluralin is very effective for controlling amsinckia, but weeds can still persist in the crop row where the trifluralin has not been applied.

• Thirty two barley grass populations were collected from grower paddocks from Eyre Peninsula and Upper North regions in 2019 and screened for resistance to major herbicide groups in 2020. This was not a random survey because most of these populations were considered difficult to control with herbicides. 
•  All of these barley grass populations collected in 2019 from Eyre Peninsula and Upper North regions were completely killed by glyphosate and paraquat and were rated as herbicide susceptible.
• Resistance to the FOP herbicide quizalofop was confirmed in 50% (n=16) of these targeted populations tested in 2020. In addition to this, 19% of the populations (n=6) were classified as developing resistance. 
• Ten barley grass populations were confirmed resistant to clethodim at 250mL/ha. At the higher clethodim dose (500mL/ha), only three populations were rated as resistant. This result is consistent with research results for annual ryegrass where higher rates of clethodim can improve weed control. Growers could improve barley grass control by increasing clethodim dose but this is unlikely to be a long-term solution to the problem. 
• Out of 1 O clethodim resistant populations, only 3 showed resistance to butroxydim at 90 g/ha and only 1 was resistant at 180 g/ha. These results are consistent with the findings from the previous year, which showed the susceptibility of many clethodim-resistant populations to butroxydim.
• Resistance to the IMI herbicides still appears to be very low in barley grass. Only one barley grass population from Eyre Peninsula was found to be highly resistant to Intercept® and showed no reduction in plant survival or biomass. 

 

It is important not to rely on a single strategy to keep resistance at bay but integrate them into the crop production program. Some of the key strategies include:

• Rotation of herbicide mode of action groups within and across years.
• Keep accurate records of your herbicide applications on a paddock basis.
• Read the herbicide product label and follow the instructions, always use robust label rates
• Rotate crop and variety.
• Identify and monitor your surviving weed populations and check for resistant weeds on your farm. Keep good records of weed populations.
• If a failure is suspected do not use the same product or product from the same mode of action group.
• Testing – confirm resistance exists. (For further information on resistance
• testing contact www.plantscienceconsulting.com.au)
• Additional cultural weed control techniques to reduce seed banks, e.g. burning, cultivation, delayed sowing,
• competitive crops and varieties, green manuring, grazing and collection of weed seed at harvest.
• Control weed escapes before the weeds set and shed viable seed.
• Do not introduce or spread weeds through contaminated seed, grain or hay.
• Consider crop and pasture topping.
• Seek advice from local advisers such as agronomists.

The herbicide tolerance of two new desi chickpea varieties (Howzat and ICCV96836) were compared to Tyson. All three varieties showed similar tolerance to a range of herbicides. Simazine, Balance + Simazine and Spinnaker applied Post Sowing PreEmergent had little effect on yield, whereas Broadstrike applied Early Post Emergent on stressed plants it suppressed yield. For the main weeds in the trial (prickly lettuce, milk thistle) the best weed control option was Balance + Simazine. In paddocks where musk is a problem the best control option will be Spinnaker.

In this trial Simazine, Diuron and Brodal were quite safe when used post sowing preemergent. However, Brodal has been known to cause crop damage when used at this stage. There are no safe early post emergent herbicides available in vetch for the control of broadleaf weeds. It appears that Morava is less tolerant of pre-emergent and in-crop herbicides compared to Blanchefleur or Languedoc.

The best overall herbicide options for controlling the most common broadleaf weeds in the southern Mallee are Simazine alone or Simazine plus Diuron, applied post sowing pre-emergent.

Rainbow vs Karoo canola - Karoo canola is tolerant to the triazines Simazine and Atrizine; however, it also appears that Karoo has a higher degree of tolerance to Lexone.

• In-crop applications of some broadleaf and grass herbicides can reduce nodulation and nitrogen fixation of peas.
• Timing of herbicide application and seasonal conditions play an important role in herbicide-legume interactions. 
• Late applications of some broadleaf and grass herbicides can reduce crop yields.

• All herbicides provided effective control of brome grass and barley grass in wheat this season.
• Crop safety in wheat was achieved by all herbicide mixes in 2008.

• 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.

• Eleven days after seeding, emergence in Minnipa and Cungena soils was higher with no fertiliser or with all the DAP banded below the seed row, compared to DAP placed with the seed or split.
• Emergence was most affected by the presence of DAP in the Streaky Bay soil, least in the Minnipa soil and Cungena soil was intermediate.
• Shoot weights decreased where DAP was placed in the seed row and this occurred in all soil types. The soil EC (salinity) was higher with DAP placed in the seed row.
• Fertiliser toxicity may be reducing wheat emergence on grey calcareous soils, even at quite low application rates of DAP at 30 kg/ha.

 

• 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.

Adequate crop nutrition following summer crop is essential for optimised winter grain yield. Soils moisture was not limiting this season, therefore wheat responses were driven by crop nutrition.

• 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.

• Large range of cocksfoot cultivars trialled at three sites: Vivonne Bay, Parndana and Stokes Bay.
• Trials will be rotationally grazed .
• Persistence and productivity will be monitored over several years, subject to further funding.

• 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.

Please refer to attached trial report for results and discussion.

• At Streaky Bay and Cungena in 2019, establishment was similar with dry sowing or sowing at the break, and at Minnipa establishment was better with dry sowing.
• There was a yield penalty if no fertiliser had been applied at Minnipa.
• Dry sowing increased grain yield at Minnipa by 0.2 t/ha compared to waiting for the break in the season.
• Dry sowing at Streaky Bay and Cungena reduced grain yield, by 0.7 and 0.3 t/ha respectively, compared to waiting for the break and sowing into a moist soil bed.
• All three sites showed a decrease in early dry matter with dry sowing.
• The herbicides and fungicides evaluated in the trial did not impact on plant establishment when dry sowing.

• The highest recorded water use efficiency (WUE) was observed at Spalding where 26.6 kg of wheat was produced per hectare for every mm of growing season rainfall.
• Growing season rainfall was below average meaning that stored summer soil moisture was very valuable in 2011.
• The WUE at Hart has been 14 kg/mm/ha or 70% calculated since 2001.

• The highest recorded water use efficiency (WUE) was observed at Spalding where 26.6 kg of wheat was produced per hectare for every mm of growing season rainfall.
• Growing season rainfall was below average meaning that stored summer soil moisture was very valuable in 2011.
• The WUE at Hart has been 14 kg/mm/ha or 70% calculated since 2001.

EverCrop research reported in this and previous Crop Updates (2010-2014) has built up a sound knowledge base on the viability, performance and economics of pasture cropping and companion annual legume based systems for fragile soils in the Northern Agricultural Region that are marginal for continuous cropping. Collectively, trials at Mingenew and Dandaragan over the past two seasons (2013 & 2014) have demonstrated that subtropical perennial grass pastures lift the overall productivity of deep sandy soils, extend the period of available green feed, convert summer rainfall into feed, reduce the winter and summer weed burden, and increase ground cover.

• Compass, Fathom and Scope CL were good competitors with weeds, which is consistent with previous years’ findings.
• Hindmarsh and Spartacus CL are poor weed competitors.
• The advantage of sowing earlier in order to increase crop competition failed to improve the competitiveness of La Trobe given the high spring rainfall.

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 use of Lucerne in the Upper Wimmera catchment and similar areas can be extended away from traditional areas such as river and creek flats.
• Introduction of lucerne into grazing systems lengthens the period of available green feed and can allow for enterprise change such as adding a lamb finishing operation to the farm business.
• Sowing time of lucerne is best suited to late winter.
• Soil testing is important to test for nutrient deficiencies and pH prior to lucerne establishment. Adequate lime and fertiliser should be applied to address deficiencies prior to establishment. Attention must be paid to ensuring that aluminium levels are suitable for lucerne production prior to sowing.
• A sub soil pH test should be taken to ensure that there are no acidity or aluminium toxicity issues at depth which could affect the lucerne plants as their roots penetrate the sub soil.
• Weed control is of critical importance before and during the establishment phase of lucerne pastures.
• Sowing depth of lucerne is important to allow an even germination. Care should be taken not to sow seed too deeply. The seed should be covered by 1 – 2 cm of soil, ensuring good soil contact.
• Control of annual grass and broadleaf weeds is of critical importance during the life of the lucerne stand if maximum production is to be achieved.
• A suitable fertiliser regime including the use of potash needs to be applied to replace nutrients removed by the lucerne system.
• Lucerne pastures can produce high quality hay which can enhance the farm’s production system if kept on farm.

1. In dryland conditions, planting in February increased yield of dryland mungbeans by 475 kg/ha over December planting.
2. Irrigation treatments increased mungbean yields by a maximum of 298 kg/ha and 653 kg/ha (planted in February and December respectively).
3. Application of water during mid pod-fill increased grain yield in the December planting but not the February planting.

The success of break crops to increase wheat production in the Eastern Wheatbelt is dependent on firstly addressing any physical and chemical soil constraints to crop production and where the previous land use is a chemical fallow. In this situation, the grain yield of lupin, chickpea, lentil and field pea was 0.97-1.42 t/ha 0.67-1.1 t/ha, 0.3-0.97 t/ha, and 1.2 t/ha respectively in a below average season. The yield of wheat following legume break crops tended to be higher than either canola or wheat planted in the remaining paddock area. The profitability of double break-crop sequences was negative in many of the sequences evaluated in this study compared to a positive profit for continuous wheat. The profitability of double break-crop sequences can be improved by the inclusion of high value legumes as the second break-crop, but further work is required to lower the risk of growing these species of crops.The yield of wheat following legume break crops tended to be higher than either canola or wheat planted in the remaining paddock area. The profitability of double break-crop sequences was negative in many of the sequences evaluated in this study compared to a positive profit for continuous wheat. The profitability of double break-crop sequences can be improved by the inclusion of high value legumes as the second break-crop, but further work is required to lower the risk of growing these species of crops.

• 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.

Wimmera had the greatest yield loss in the presence of weeds and produced the highest weed yield. Hindmarsh also produced the same weed yield. Both of these varieties should not be sown into weedy paddocks unless there is a good management strategy. Scope, Buloke and Compass were identified as very competitive varieties, with the least amount of yield loss and weed seed production. Generally, the presence of weeds reduced barley yields by 1.4t/ha on a 5.4t/ha crop (mean of all varieties).

Crop stubbles provide a valuable feed source for stock over the summer period. The results from this trial indicate that grazing stubbles does not reduce either the amount of soil water stored during the summer fallow period or subsequent crop yield. In low rainfall environments, it is rarely possible to grow sufficient stubble to improve summer fallow efficiency by reducing evaporation (>5t/ha): growers should make use of this valuable feed source. Growers should maintain at least 70 per cent stubble cover (about 2t/ha of cereal stubble) to minimise the risk of wind erosion.

• Minnipa Agriculture Centre results showed significant yield advantage with earlier sowing in trial data even in a great season.
• Weeds can have a large effect on early sown crops, but most farmers try to have some paddocks set up to sow early.
• If early sowing is an option take advantage of it.

• The wheat yields were quite acceptable considering the time of year they were sown. The average yield of 3.2 t/ha is still economic, even if feed prices are used. 
• The four winter wheat varieties grown in the trial are not suited for a July sowing, as the risk of stem rust carrying over summer, to infect the following years crop, is too high. In addition, if sowing has to be delayed into July, then a shorter season variety with the potential to make milling quality should be the preferred option. Winter wheats should only be grown if they can be sown early to maximise their high yield potential. 
• If the yield loss between the June and the July sowing at the Hamilton site is analysed, then an average yield loss of 26 kg/hectare/day is obtained. In other words for every week you delay sowing you are losing 180 kg/ha of wheat yield. 

• Summer weed control is not a luxury item and should be considered an essential expense.
• The financial reward of timely summer weed control far outweighs the outlay and this was again proven in 2006.
• Expenditure on summer weed control can be minimised if weeds are sprayed early.

The results of the trial confirmed what we expected to see from kikuyu pastures – better growth rates through Summer/Autumn, lower supplementary feed cost, more wool growth with a higher tensile strength and better Vitamin E status.

• In terms of feed value, kikuyu out performed the annual pastures for nearly all criteria during the spring/summer period.
• Kikuyu paddocks were able to sustain a higher stocking rate than the annual paddocks over the spring/summer period.

This demonstration investigated knockdown weed control options prior to sowing. For the knockdown control of ryegrass, canola and wild radish prior to sowing, glyphosate is quite effective and no additional herbicides are generally required. Glyphosate is weak on marshmallow and a group G herbicide is required as a mix with the glyphosate. To reduce the risk of group M (glyphosate) resistance developing in ryegrass it is strongly recommended to use the ‘double knock’ approach (glyphosate followed four to seven days later by SpraySeed®) on at least some paddocks every year.

• It is no longer a question of whether ryegrass will become resistant; it is when! 
• Double knock was the most effective treatment for managing this ryegrass population  (98% control).
• Alternative crop options should be integrated into the rotation to manage weeds and reduce the reliance of glyphosate. 
• High water rates, spraying closer to evening and no later than 7-10 days after the initial knockdown are essential when using Paraquat.

Lambs grazed on forage brassica at Jil Jil from November 2011 to early January 2012 achieved adequate growth rates (230 g/head/day). The forage brassica provided green paddock feed for nearly two months during harvest, saving stubbles for later use and avoiding hand feeding.

2018 Season 

• While growing season conditions were dry and grain yields were low and therefore not profitable, both Bolt lentils and Gunyah field peas yielded highest of the 5 break crop species grown at the Salmon Gums demonstration site. Soil boron levels were relatively high at this site.
• Following waterlogged conditions in August, Bonito canola out yielded the 4 four legume break crop species grown at the Gibson demonstration site, with Samira faba beans a close second.
• The addition of an extra 72 Units of nitrogen (171L Flexi-N delivered in 3 incremental applications) to the 5 break crops at the Gibson demonstration site resulted in significant increases in yield and earnings before tax profit in both Bonito canola and Samira faba beans but made little difference to the performance of PBA Strikers chickpeas, Morava vetch and Jurien lupins. The addition of extra nitrogen to Faba beans lifted yield by an average of 0.763t/ha taking it to 2.473t/ha which was close to the average yield of un-topped-up canola (2.169t/ha).
• In terms of earnings before tax, the faba bean crop was the most profitable of the 5 break crops grown at Gibson. It is important to note though that the $800/tonne price seen for faba beans in February 2018 was well above both the five and ten year average for this crop.

2019 Season 

• Annual rainfall was well below average in 2019 at all 5 demonstration sites in the Esperance Port Zone and an unprecedented frost event in September affected crop flowering at the Ravensthorpe, Salmon Gums and Beaumont sites. It’s important these seasonal conditions are factored to in to interpretation of legume crop performance at these sites.
• Poor growing conditions at the Ravensthorpe demonstration site resulted in very low yields and none of the break crops grown were profitable. The State Government declared part of the Ravensthorpe Shire as water deficient on 7th May 2019 and further parts of the Shire on 13th February 2020.
• Reasonable rainfall in August stimulated germination of broadleaf weeds resulting in a higher than ideal weed burden in all break crop species strips at the Ravensthorpe site. This highlights the limited control options available for late weed germination in legumes.
• At the Coomalbidgup demonstration site while lupins yielded highest of the break crop species grown, they were not profitable, making an EBT tax loss. Chickpeas were the only profitable break crop species grown at this site; lower seasonal rainfall meant the waterlogging conditions that commonly prevail at this location were not a constraint on chickpea yield. An average rainfall year would likely result in chickpea yield losses due to their susceptibility waterlogging.
• Dry conditions at the start of the season at Coomalbidgup reduced herbicide efficacy but the site did not have a high background broadleaf weed pressure so competition was unlikely to have greatly reduced crop yield.
• Poor growing conditions at the Beaumont demonstration site, which entailed a dry start, a severe frost at flowering and a very dry finish resulted in none of the 5 break crops grown performing profitably. The dry start at this site affected plant establishment of the chickpeas and faba beans in particular. Seeding equipment issues handling the large seed size of the faba beans also reduced establishment of the beans.
• Poor growing conditions, which entailed 2 dry preceding years resulting in very low subsoil moisture at the start of the season, a dry start, a dry growing season, a severe frost at flowering and a dry finish meant that Scepter wheat yields were below average at the Salmon Gums demonstration site. There was no significant difference in wheat yields achieved between the 2018 break crop species treatments. Scepter was profitable after each of the 2018 break crop species except in those replicates following vetch. Wheat after lentils were most profitable with an EBT return of $50/ha, followed by wheat after field peas at $34/ha.
• At the Gibson Demonstration Site wheat following vetch grown in 2018 yielded highest and was therefore the most profitable. Wheat following faba beans and lupins grown in 2018 yielded next highest; their yields being statistically similar. Wheat in replicates following 2018 canola and chickpeas were similar and yielded lowest of the 2018 break crop species treatments.
• Wheat yield in replicates that received an additional 171L/ha of Flexi N in 2018 yielded higher than those that did not and as such were more profitable.
• Tissue test data and wheat yields achieved at the Gibson site suggested nitrogen carryover from 2018 to the 2019 cropping season had occurred. This was not reflected in the pre-seeding soil test data demonstrating the significance of low soil moisture in impeding soil nitrogen mineralization. These results emphasise the importance of understanding mineralization when interpreting soil test results in dry conditions and the merits of coupling autumn soil testing with in-crop tissue or soil testing to support in-crop nutrition decisions.

• Commercial viability has been difficult to demonstrate.
• Field trials demonstrated that the H Senor was able to accurately classify annual ryegrass in several broadleaf crops, including canola, faba bean, lentil and field pea.
• Other grass weeds such as brome grass and wild oats were also correctly identified as grasses in these crops.
• Broad leaf weeds were accurately classified in cereal crops, however this was more difficult due to the overlapping nature of the cereal crops at the time when the broadleaf weeds had emerged.
• Classification accuracy was lower for detection of grass weeds in cereal crops and broadleaf weeds in broadleaf crops, and these scenarios were not pursued for that reason.  

Soluble herbicides utilised in controlling broadleaved weeds in lentils can have significant impact on growth. Ensuring that soil throw is minimised back into the seed row is paramount. Also understand soil moisture levels prior to applying some herbicides and the impact this factor will have on uptake and persistence

• Key Messages: SP1333 and PBA Hallmark XT showed little to no signs of herbicide damage at x0.25 gai/ha and 376 gai/ha. At higher herbicide rates SP1333 showed lower herbicide damage than PBA Hallmark XT, but grain yield results were unreliable due to shattering in SP1333.

• Establishment and Plant Growth: Application of ‘Gp C’ PSPE had little or no impact on emergence and early plant growth. Lentils had optimum establishment and growth as a result of adequate soil moisture at sowing and favourable conditions during the rest of the season. Growth, development and yield were not affected by the few frost events, which occurred in the spring.

• Herbicide Damage: Both varieties did not show symptoms of herbicide damage at lower rates (x0.25 and x0.5 gai/ha) irrespective of the time of application (Table 1). However, at higher rates (x1 and x2 gai/ha) the new variety SP1333 showed less damage than PBA Hallmark XT. At x2 gai/ha, PSPE damaged SP1333 more whereas application at 4 node stage was more detrimental for PBA Hallmark XT.

• Number of weeds: Better control of weeds were achieved when ‘Gp C’ was applied as PSPE or 4 node applications at rates above x0.5 gai/ha (Table 2). Almost full weed control was seen in the x1 gai/ha and above for both PSPE and 4 node treatments. Weed densities were not different between varieties.

• Biomass at flowering: At flowering varieties were not significantly different in biomass. In PBA Hallmark XT biomass improved when low rates (x0.25 and x0.5 gai/ha) were applied as PSPE spray but decreased at the highest ‘Gp C’ rate (x2 gai/ha) applied as PSPE or 4 node stage spray, compared to the plants which did not receive herbicides (Table 3). This indicates that application of ‘Gp C’ at lower rates as PSPE sprays in PBA Hallmark XT can effectively control weeds without the crop damage or biomass loss, as oppose to higher rates. However, rates or times of herbicide application did not cause any biomass change in SP1333.

Light grazing was shown to leave most of the crop residue horizontal and detached but there were similar amounts of residue to the ungrazed plots. Grazing over summer and winter reduced crop yield at one site and further work on this may be required.

It is critically important to sample soil pH to depth prior to investing large sums in lime application and incorporation. Typically it has been found that on sandplain soils the yield benefit of one-off deep cultivation or deep ripping is large enough to cover the cost of the tillage in the first year so the subsequent productivity benefits associated with more rapidly fixing the soil pH by incorporating lime can be realised sooner. Other factors such as water repellence, herbicide resistant weeds, subsoil compaction, wind erosion risk and soil type will impact on the choice of incorporation implement used.

• For the first time sheep grazing behaviour in a Mallee paddock was monitored and mapped using GPS tracking collars.
• Sheep grazed the entire stubble paddock as they sought out spilt grain during the summer fallow, but they preferred to graze on sandy soil types first.
• While grazing a vetch pasture in the same paddock, livestock spent 50% of the time grazing only 25% of the paddock and 25% of the paddock was not utilised. (iv) At least $4000 profit was foregone from the paddock through the under-utilisation of the vetch pasture.
• Within-paddock fencing technology in large Mallee paddocks has the potential to capture this potential profit by improving feed utilisation.

• For the first time sheep grazing behaviour in a Mallee paddock was monitored and mapped using GPS tracking collars.
• Sheep grazed the entire stubble paddock as they sought out spilt grain during the summer fallow, but they preferred to graze on sandy soil types first.
• While grazing a vetch pasture in the same paddock, livestock spent 50% of the time grazing only 25% of the paddock and 25% of the paddock was not utilised.

• No till treatments have been higher yielding and more profitable in continuous cropping rotations. Cultivation has increased yield and profit in 18 month fallow rotations.
• Two cereals followed by a break crop of either fieldpeas or canola no till has been the most profitable rotation. Interestingly 16 years continuous wheat has not been too far behind.
• Weed spectrum and numbers have changed dramatically within rotations and tillage methods. Interestingly no till treatments have hosted less weeds than cultivated treatments.
• One year of no pre emergent herbicide has taken the trial back 6 years and allowed large numbers of ryegrass to again become established and set seed.

• After 18 years there was no standout rotation, in terms of profitability, in any given season. All  rotations had their pros and cons in both wet and dry years. Therefore having a mix
  of rotations and doing things on time is a recipe for a resilient business.
• The most profitable rotation for the duration of the trial was the continuous cropping rotation, which included two wheat crops followed by a pulse crop in a no-till system. The addition of the pulse crop every third year was beneficial, especially for adding extra nitrogen, however added issues such as broadleaf weed blowouts with weeds like fumitory.

• Commercial viability has been difficult to demonstrate.
• Field trials demonstrated that the H Senor was able to accurately classify annual ryegrass in several broadleaf crops, including canola, faba bean, lentil and field pea.
• Other grass weeds such as brome grass and wild oats were also correctly identified as grasses in these crops.
• Broad leaf weeds were accurately classified in cereal crops, however this was more difficult due to the overlapping nature of the cereal crops at the time when the broadleaf weeds had emerged.
• Classification accuracy was lower for detection of grass weeds in cereal crops and broadleaf weeds in broadleaf crops, and these scenarios were not pursued for that reason.  

Using a combine harvester to manage stubble at harvest was expensive and exposed crops to greater risk of weather damage.  Harvesting tall and inter-row sowing was the cheapest form of stubble management and also gave good establishment.  Burning is cheap and effective at removing stubble, and allowed excellent establishment and greater early vigor for competition with weeds, but may not suit all paddock types.

• In 2017, don’t let stubble compromise the big things (weeds, disease, timeliness).

• Allowing weeds to grow during summer reduced subsequent wheat yield by more than 50 percent
• Provided summer weeds were controlled, other surface treatments (slashed stubble, standing stubble, cultivation, bare earth) had little effect on crop yield
• Controlling summer weeds is one of the most cost-effective input investments available to growers in the Mallee, returning $5 for every $1 invested in this demonstration.

In years with high summer rainfall, growing break crops is low risk and is an effective management strategy for reducing weeds, while growing profitability. Two year breaks are better than one at achieving favourable returns and reducing brome grass populations. The best brome grass control and gross margins were achieved by two year rotations of Clearfield canola/vetch and continuous Clearfield wheat followed by wheat.

• Incorrect identification could be costly as with Take all and Crown rot require different management.
• Check the bases of plants for symptoms, don’t rely on whiteheads (which need not even be disease related).
• Even where whiteheads are not present, significant yield losses can occur.
• Know the risk of yield loss in your paddocks before sowing. For 2012 crops, this will mean sending summer/autumn soil samples to the Predicta B testing service for analysis.
• The most effective management tool for both diseases is host-free breaks.
• Where old cereal rows have medium to high inoculum levels, sowing between those old rows can reduce yield losses from these diseases, but only if the inter-row has low levels of inoculum.
• When Take-all inoculum levels are medium to high, the best option is a 12 month break from hosts. If susceptible cereals must be sown, keep the paddock(s) weed free and sow the atrisk paddock(s) last in the cereal cropping program.
• When crown rot inoculum levels are medium to high, the best option is a break from hosts (2-3 years may be needed). If cereals must be sown then barley is least likely to show yield loss, followed by oats and bread wheat. Do not apply excessive nitrogen early in the season.

Barley can be successfully grown on retained wheat stubble, but it is advisable to burn wheat stubble when growing wheat on wheat. If stubble is retained then Yellow Leaf Spot can be a devastating disease in a wet winter. The most important management practices when growing a cereal on cereal are as follows:

• Select paddocks with low numbers of grass weeds.
• Retain wheat stubble for barley, burn the stubble for wheat.
• Control summer weeds to ensure summer rainfall can be used by the crop.
• Use varieties with good disease resistance such as Silverstar or Krichauff.
• Disease - select paddocks with low disease pressure (monitor the previous crop) and DNA test the paddock prior to sowing.
•  Apply sufficient nitrogen for a good crop (soil test to know how much to apply).
• Barley on barley can lead to serious problems with leaf diseases such as net blotch.

• Lucerne target establishment density for dryland environments should not exceed 50 plants/m2; or 28 plants/m of drill row.
• Changing row configuration did not increase lucerne persistence.
• Sowing lucerne with a cover crop reduced final lucerne density by 39%.
• Lucerne mortality is affected more by summer conditions than the presence of wintergrowing companion species, such as phalaris or subterranean clover.

• Maintaining ryegrass seedbanks at low levels is critical due to the weeds competitive nature and ability to rapidly evolve resistance

• Effective management strategies in a canola and wheat cropping rotation can provide long-term management of Group A resistant ryegrass

• This trial was conducted in Victoria; varieties and some technologies utilised in this trial are not registered for use in South Australia.

Increasing plant density is a tool to improve a crop’s competitiveness against weeds. This strategy did not adversely affect the yield of the varieties at the Liebe Main Trial Site in 2012. 

Nitrogen treatments did not significantly influence crop yield however, did influence grain protein. The soil nitrogen levels and season are likely to have influenced this result. Soil testing and understanding the crops requirements as the season unfolds are useful strategies to manage crop performance economically.

The environment is likely to have had the bigger influence on the performance of the varieties than plant density or nitrogen. Growing season rainfall for 2012 was lower than average and disease patches (likely Rhizoctonia) were evident at the trial. The water use efficiency at the site was 13 kg/mm given growing season rainfall (April to October) was 133mm (plus 34mm in January) and grain yields of 1.98 t/ha across whole trial.