Farmers planning to renovate pasture’s can face an almost bewildering choice of varieties to select from. Victorian perennial rye grass is one of the best known of the ryegrass varieties and is still used by many. However, given it was developed and released in the early 1900’s it’s been superseded by many new and improved varieties. To look at this another way, this would compare to you buying rams from a breeder that had not done any genetic improvement in his flock for 100 years. 

• New post emergent broadleaf herbicides Torpedo, Conclude, Precept and Velocity generally gave good control of pulses or canola.
• Pre-emergent grass herbicides had no effect on the growth of pulses or canola.

• In 2021 lentils produced similar yields from April 1 to May 14.
• Chickpeas sown in April were lower yielding, with high rates of flower abortion. Highest yield was achieved by sowing in mid-May.

• 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.  

• Most varieties yielded did not incur yield loss from crop topping at the recommended timing indicating that they were well suited to crop topping at the recommended timing for rye grass control in 2014 where the season finished rapidly due to dry conditions.
• As found in previous seasons there is not always a direct correlation between variety flowering and maturity timing and yield loss due to crop-topping.

• In 2020 lentils produced similar biomass from all times of sowing.
• Seed yields were highest from June sowing.

 

• PBA Hallmark XT handled SU residues better than PBA Bolt
• Lentils should not be sprayed with Metribuzin on light lands until metribuzin tolerant varieties are made available. 
• Until that time IMI herbicides and XT lentils are probably the safest option on light lands in WA or consider alternative species.

• PBA Highland XT produced higher yields than the standard variety PBA Bolt
• PBA Highland XT appeared to have better herbicide tolerance than PBA Bolt
• Deeper sowing and rolling immediately after sowing increased crop safety and yields
• Applying soil active herbicides prior to sowing increased crop safety

Managing brome grass populations in wheat is a challenge facing many growers, however chemical and variety control options have improved over the years with the introduction of Clearfield wheat technology and now metribuzin tolerant wheats.

• 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.  

• Including legume crops and pastures in rotations increases soil nitrogen even two years after the legume break was grown.
• Brown manure vetch has proven to be the best break phase for increasing soil mineral nitrogen.
• Crop sequences have had small and variable effects on plant available soil water.
• Rhizoctonia inoculum levels are highest following cereal crops and high Rhizoctonia levels have corresponded with poor root health. Canola decreased inoculum levels to levels similar to a fallow.
• High brome grass numbers re-emerged two years after a one year break.

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.

• At present, group A herbicide resistance in barley grass is relatively low at a district level on the EP. However, growers need to act now to integrate multiple control tactics to prolong the effectiveness of these cheap and effective herbicides.
• In the absence of group A herbicides, it is still possible to achieve large reductions in barley grass seed bank in a legume pasture phase.
• When using moderate efficacy-low cost herbicides (Treflan + Logran) for barley grass control in wheat, effective control of the weed in previous pasture phase was critical.

• Increasing incidence of barley grass in cropping paddocks in southern Australia is likely to be associated with selection of more dormant biotypes by weed management practices used by growers.
• In some districts, barley grass management is now being complicated by the evolution of group A resistance. However, there appear to be several effective potential herbicide alternatives for barley grass control in broadleaf crops.
• Integrated weed management strategies are critical to delay onset of herbicide resistant barley grass.

• If crown rot is a concern, conduct a DNA test before sowing a susceptible cereal in 2007.
• Break crops and grass free fallows are still the best practice for reducing crown rot inoculum levels.
• If inoculum levels are high, it will take at least two years free from grass and volunteers, to reduce levels significantly.

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.

• Pulses are more vulnerable to yield loss from heat and frost stress in a critical period centred around early podding.

• Sowing time and variety choice are crucial to reduce risk of stress at this stage.

• We define the safer window for the critical period as less than 10% chance of frost (0oC in the Stevenson screen) and less than 30% chance of heat (>34oC in the Stevenson screen).

• In environments of upper Eyre Peninsula, such as Minnipa, there is limited frost risk, hence early sowing will minimise heat risk and maximise potential yield.

• However, at sites such as Laura (Mid North), there is a safer window after frost and before heat.

• Results should be considered in conjunction with grower specific conditions and the trade-off between early sowing, weed and disease management and rainfall.

UAV imagery with appropriate analysis has the potential to identify weed issues in paddocks quickly, reliably and cheaply over large areas.

• UAV imagery with skilled specialist analysis and programs has the potential to identify and map weed issues in paddocks.
• Grass weed patches are easier to identify in legume and pasture crops than cereal crops.
• Variability in germination and crop growth makes it harder to identify grass weed areas.
• Data capture and analysis for analytical purposes such as grass weed mapping in individual paddocks will be beyond the skills of most farm businesses unless farmers have a special interest in this area.
• Group A resistant barley grass has once again been detected at the Minnipa Agricultural Centre. Barley grass resistance to Group A herbicides has been detected three times in three years, so be aware it is present current farming systems.

• UAV imagery with skilled specialist analysis has the potential to identify weed issues in paddocks.
• It was easier to identify grass weed patches in legume and pasture crops than cereal crops.
• Data capture and analysis for analytical purposes such as grass weed mapping in individual paddocks will be beyond most farm enterprises unless farmers have a special interest in this area.
• Grass patches were more reliably identified using UAV data captured at higher resolutions.
• Barley grass resistance to Group A herbicides has been detected several times throughout the project, so be aware it may be present in current farming systems. 

 

• Monza efficacy on brome grass has not been reduced by the addition of these herbicides and insecticides at the final assessment.
• Some of the treatments were significantly different at the early timing, but the final assessment showed no significant difference.
• Crop phytotoxicity and crop yield were not measured.

• Of the herbicides tested, Glyphosate is the most cost effective and reliable herbicide. ‘FOP’ grass selectives appeared to give poor control at the rates used on mature button grass. Intervix appeared to give poor results at the rates used on mature grass.
• A tankmix of Glyphosate with other broadleaf and melon herbicides reduced control by 13% at 17 days after spraying. Spraying in the dark appeared to give the best control, spraying in the early morning daylight gave no significant improvement in control.
• Choice of adjuvant proved important, with LI700 and Amsul giving the best performance by 17 days after application. The use of Hot-Up oil and Supercharge oil + Amsul gave slightly poorer control of Button Grass. Paraquat at 1L & 2L/Ha and Alliance at 3L/Ha achieved impressive initial burndown at 10 days, but weed regrowth occurred shortly after and was unacceptable at 17 Days after application.

 

• Weed sensing and selective spot spraying with machinery such as the WEEDSEEKER and WEED-IT selective spot sprayers has allowed for very cost effective broadacre spot spraying of weeds without spraying the whole paddock area.
• Selective spot spraying of hard to kill summer weeds is one application where this technology has a potential to save growers significant funds usually allocated to herbicides.
• Elevated rates of non-traditional or previously cost prohibited herbicides of a different resistance group can now be used to achieve much more reliable and faster control of herbicide resistant weeds.
• Robust rates of Glyphosate provided the most acceptable levels of control across the 3 winter weeds species tested.
• Gramoxone and Sprayseed at rates of 2L & 4L gave good control of brome grass, but both annual ryegrass and wild radish grew back and at the final ratings showed unacceptable levels of control.
• In a region where Glyphosate tolerant ryegrass populations have been identified, the lack of alternative modes of action to reliably control annual ryegrass and wild radish in fallow is of real concern.

• Weed sensing and selective spot spraying with machinery such as the WEEDSEEKER and WEED-IT selective spot sprayers has allowed for very cost effective broadacre spot spraying of weeds without spraying the whole paddock area.
• Selective spot spraying of hard to kill summer weeds is one application where this technology has a potential to save growers significant funds usually allocated to herbicides.
• Elevated rates of non-traditional or previously cost prohibited herbicides of a different resistance group can now be used to achieve much more reliable and faster control of herbicide resistant weeds.
• Robust rates of Glyphosate provided the most acceptable levels of control across the 3 winter weeds species tested.
• Gramoxone and Sprayseed at rates of 2L & 4L gave good control of brome grass, but both annual ryegrass and wild radish grew back and at the final ratings showed unacceptable levels of control.
• In a region where Glyphosate tolerant ryegrass populations have been identified, the lack of alternative modes of action to reliably control annual ryegrass and wild radish in fallow is of real concern.

• Weed sensing and selective spot spraying with machinery such as the WEEDSEEKER and WEED-IT selective spot sprayers has allowed for very cost effective broadacre spot spraying of weeds without spraying the whole paddock area.
• Selective spot spraying of hard to kill summer weeds is one application where this technology has a potential to save growers significant funds usually allocated to herbicides.
• Elevated rates of non-traditional or previously cost prohibited herbicides of a different resistance group can now be used to achieve much more reliable and faster control of herbicide resistant weeds.
• Robust rates of Glyphosate provided the most acceptable levels of control across the 3 winter weeds species tested.
• Gramoxone and Sprayseed at rates of 2L & 4L gave good control of brome grass, but both annual ryegrass and wild radish grew back and at the final ratings showed unacceptable levels of control.
• In a region where Glyphosate tolerant ryegrass populations have been identified, the lack of alternative modes of action to reliably control annual ryegrass and wild radish in fallow is of real concern.

• Weed sensing and selective spot spraying with machinery such as the WEEDSEEKER and WEED-IT selective spot sprayers has allowed for very cost effective broadacre spot spraying of weeds without spraying the whole paddock area.
• Selective spot spraying of hard to kill summer weeds is one application where this technology has a potential to save growers significant funds usually allocated to herbicides.
• Elevated rates of non-traditional or previously cost prohibited herbicides of a different resistance group can now be used to achieve much more reliable and faster control of herbicide resistant weeds.
• Robust rates of Glyphosate provided the most acceptable levels of control across the 3 winter weeds species tested.
• Gramoxone and Sprayseed at rates of 2L & 4L gave good control of brome grass, but both annual ryegrass and wild radish grew back and at the final ratings showed unacceptable levels of control.
• In a region where Glyphosate tolerant ryegrass populations have been identified, the lack of alternative modes of action to reliably control annual ryegrass and wild radish in fallow is of real concern.

• Gramoxone at 1.0L/Ha is the best & most cost effective treatment for fast grass control in the short period before sowing
• If the sprayed grass paddock is left un-sown for several days, the Glyphosate and Boxer Gold treatment proved to have slower visual control but more reliable grass control over the longer period (95%).
• The high rate of Glyphosate CT (2.0L/Ha) was also quite good at the later time of rating (24DAA), 1.0L/Ha did not provide acceptable control (77%)
• Rainfall after application would have greatly enhanced the activity of the soil residual herbicides such as Boxer Gold, Sakura and Outlook
• The possible foliar absorption of Boxer Gold when mixed with Glyphosate made it a clear winner in this trial. It was by far the cleanest treatment at 24 DAA in the absence of tillage. Gramoxone + Sakura(92%) & Gramoxone + Outlook (90%) were very close behind (no tillage).
• Addition of Logran B Power or Hammer did not improve ryegrass control when mixed with Roundup CT or Gramoxone.
• Addition of 500ml Alliance to 1.0L Gramoxone may improve broadleaf weed control, particularly small capeweed, but no improvement in grass control.

Native grass pastures can be successfully established to provide grazing potential for stock.

• Ryegrass is an increasingly significant weed in the SE of SA and Western Victoria due resistance to major knockdown, pre emergent and post emergent herbicide chemistries.
• As resistance develops to post emergent chemistry, pre emergent chemistry becomes increasingly important in managing resistant ryegrass.
• Knowing the resistance status of weeds within a paddock allows for the most cost effective herbicide to be applied....the most expensive herbicide is the one that doesn’t work.
• Incorporating alternative herbicide modes of action can improve ryegrass control especially where the presence of Group D resistant ryegrass is suspected or known.

Although the panic grasses at the Buntine site have shown excellent presistence, despite the extended dry conditions, there remains a question mark over the role of sub-tropical grasses in the north-eastern wheatbelt.

In a dry year hybrid RR canola with no applied nitrogen produced the best returns to growers. RR hybrids had higher oil and applying N reduced oil more than it increase yield. With TT technology CB Telfer the most popular variety in the low rainfall area produced the best combination of oil and yield. Hybrid TT was not superior to OP TT’s at Grass Patch in 2012. Late applications of N produced similar yield responses to earlier N applications.

Nitrogen application to optimise waterlogging recovery

Please see attached trial report for results.

Please see attached trial report for results.

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

• 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.  

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

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

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

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

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

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

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

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

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

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

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

• It is difficult to effectively control witch grass in summer.
• No single herbicide treatment achieved 100% control.
• Glyphosate-based herbicide treatments were the best performers, achieving 86–88% control.
• The mixture of glyphosate + simazine had residual control on subsequent emergences.

For results please see the attached trial report.

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

Increased crop density reduced annual ryegrass density.

Herbicides offered effective weed control, and performance of Sakura® and Boxer Gold® was similar in this season.

Triflur X® provided excellent control of barley grass over the entire site, although by August, weed density was lower following Triflur X® at 3L/ha rather than 2L/ha.

In 2020, Intervix® provided excellent control in-crop, preventing panicle production. In 2021 the field was too wet to spray in-crop herbicides.

Increased seeding rate increased crop density, and resulted in a non-significant reduction to barley grass panicles.

• From the statistical analyses performed on this trial it is concluded that Paraquat at 1L with adjvant LI700 at 0.5% is most efficient in causing fast brownout on Paddy Melons, Wild Radish, Serradella, Mint weed, Capeweed, Couch grass and Blue Lupins.  

• Chaff lining is an evolving harvest weed seed control method
• It presents as a low cost, easy weed management tool
• It is considered to be good control for ryegrass and radish but not as successful for brome grass

• Canola is not a break crop in paddocks if root lesion nematodes (RLN) and Rhizoctonia solani are both present
• Weed free legumes, pulses and pastures are the best options where RLN and R. solani co-exist in a paddock
• Cereals substantially increase RLN and R. solani levels while canola will also increase RLN

A break of two years can produce a better financial outcome than continuous wheat over a four year period of production where there are substantial pressures on wheat performance (eg. grassy weeds). Wheat yields after a two year break were a significant step up from wheat crops following a one year break, which were in turn, much better than the continuous wheat. Large break crop benefits of 0.5-1.25 t/ha were achieved following a two year non-cereal break phase compared to continuous wheat. The break crop benefit of a one year break may only last one season if grass weeds are a significant factor. The major benefit of breaks in these long term cereal paddocks was to reduce grassy weed pressures for subsequent wheat crops phases. The benefit of a two year break had little to do with the phases chosen for those two breaks, providing that excellent grass weed control could be achieved in both. Many of the most profitable crop sequences over the four year period often started with a two year break phase.

• Continuously cropping cereals has increased grass weeds and root disease to a point that it is no longer the most economical option, due to decreased yield and costs associated with addressing weed and disease issues.      
• Two year breaks starting to pay their way in the third year of the rotation. One year breaks have lifted wheat performance but have not kept grassy weeds or diseases under control.

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

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

This trial was conducted to evaluate the residual control of button grass in fallow. An establishment of button grass was already present at the site with the majority of weeds ~15-25cm in diameter. These weeds were controlled with Roundup 450 @4L/ ha + Liase @1%. Residual treatments were applied on the 19/11/18, 5 days after the Roundup application.
Significant rain events occurred 3 days after residual application (52mm) and 29 days after application (30mm). There was no new emergence of button grass even in the untreated areas. A second maintenance spray of Roundup was applied to control any surviving mature button grass plants ~30 days after the residual herbicide application. Assessment on the 5/2/19 (77 days after application) still showed no new button grass emergence.
Additional rain events occurred in March 2019 (85mm on 16/3/19 and 35mm on 30/3/19) with an assessment of control conducted on the 1/5/19 (163 days after application). The majority of button grass at this assessment were flowered, up to ~30cm in diameter and expected to have emerged following the March rainfall. Dual Gold 2L provided ~99% control of the emergence flush with Flame at 150-200 mL/ha in excess of 90% control. Stomp Xtra and Valor provided useful levels of suppression and controlled ~70-80% of the emergence. Neither Balance 100 g/ha nor Terbyne Xtreme 1.2 kg/ha provided any button grass control and there was no obvious indication of biomass suppression.

This trial was conducted to evaluate the residual control of button grass in fallow. An establishment of button grass was already present at the site with the majority of weeds ~15-25cm in diameter. These weeds were controlled with Roundup 450 @4L/ ha + Liase @1%. Residual treatments were applied on the 19/11/18, 5 days after the Roundup application.
Significant rain events occurred 3 days after residual application (52mm) and 29 days after application (30mm). There was no new emergence of button grass even in the untreated areas. A second maintenance spray of Roundup was applied to control any surviving mature button grass plants ~30 days after the residual herbicide application. Assessment on the 5/2/19 (77 days after application) still showed no new button grass emergence.
Additional rain events occurred in March 2019 (85mm on 16/3/19 and 35mm on 30/3/19) with an assessment of control conducted on the 1/5/19 (163 days after application). The majority of button grass at this assessment were flowered, up to ~30cm in diameter and expected to have emerged following the March rainfall. Dual Gold 2L provided ~99% control of the emergence flush with Flame at 150-200 mL/ha in excess of 90% control. Stomp Xtra and Valor provided useful levels of suppression and controlled ~70-80% of the emergence. Neither Balance 100 g/ha nor Terbyne Xtreme 1.2 kg/ha provided any button grass control and there was no obvious indication of biomass suppression.

The trial was conducted in a paddock near Bellata in Northern NSW that was fallowed from faba beans in 2020. Stubble levels were low and the paddock was sown to LRPB Lancer wheat in early May.
The majority of herbicide treatments were applied in late April and incorporated by sowing (IBS) 5 days later using a John Deere single disc planter on 38 cm row spacings. Rainfall totaling 11 mm was recorded 3-4 days after planting (3-4 DAP) with an additional 7 mm within the first fortnight. One herbicide was applied as a post sowing pre-emergent (PSPE) split application, 5 days after sowing and the remaining 3 treatments applied at an early post-emergent timing in wheat, at ~4 leaf crop stage.
Wheat establishment was assessed at 12 DAP when a majority of plants were already at ~1-2 leaf stage. The untreated population was ~96 plants/m2. Severe damage to crop emergence was apparent from a number of herbicides.
Treatments containing trifluralin (TriflurX or Bolta Duo) caused the greatest damage and reduced crop emergence by >90% (0-8 plants/m2). Rifle 440 (pendimethalin) and Luximax (cinmethylin) had less impact but still reduced emergence by ~50-60% (50 and 37 plants/m2). Diablo Duo (triallate and prosulfocarb) reduced emergence by ~15% (82 plants/m2). No other treatment had a significant impact on crop emergence although there was a non-significant trend to a ~10% reduction in emergence from both Boxer Gold (s-metolachlor plus prosulfocarb) treatments and Overwatch (bixlozone). There was no effect on crop emergence from Sakura or Dual Gold. A second assessment of emergence was not conducted, as there was no apparent change in crop emergence at later inspections.
Trace levels of paradoxa grass were apparent at 23 DAP when the in-crop treatments were applied but with no detection in the untreated. Paradoxa grass control was assessed in late June at 59 DAP with a density of ~0.7 plants/m2 in the untreated. All herbicides significantly reduced the weed counts under a low paradoxa grass density. Sakura, the split application of Boxer Gold, Luximax and all treatments containing trifluralin reduced paradoxa grass counts by >90%. Arcade 3 L/ha and Mateno Complete applied at 23 DAP also reduced paradoxa counts by >90%.
All treatments provided useful levels of suppression or control of paradoxa grass for ~3-7 weeks after application. All herbicides with paradoxa grass control claims provided >90% reduction in counts with encouraging activity from the split application of Boxer Gold, Luximax and Arcade 3 L/ha applied 23 DAP.
An effective commercial knockdown spray was applied shortly after the 59 DAP assessment. The site was inspected in August and October with no new paradoxa grass emergence in the untreated but trace levels where severe crop damage had occurred.
This trial however was an example where residual herbicide crop safety was very poor. The actual cause is unclear but may be due to a combination of early planting with very rapid seedling development (wheat to 2 leaf by 12 DAP) and the use of a single disc planter which failed to remove adequate soil from the planting furrow. Depth of planting was unfortunately not assessed but the rapid crop emergence would suggest planting seed was relatively shallow. Rainfall after planting was obviously a factor but the amounts were relatively low with ~8 mm at 3 DAP and ~3 mm at 4 DAP.
In this situation, with low paradoxa grass density, the treatments with the best combination of crop safety and paradoxa grass efficacy were Sakura, Mateno Complete and Arcade 3 L/ha.

This trial was established to evaluate the residual control of Feathertop Rhodes (FTR) grass in wheat. Stubble levels were extremely low with the paddock long fallowed from sorghum in 2019/20.
The majority of treatments were applied 3 days prior to planting (-3 DAP) and incorporated by sowing (IBS) using a commercial disc planter on 28cm row spacing. The post sowing pre-emergent treatment (PSPE) was applied 4 days after planting. No rainfall was recorded between the IBS and PSPE applications with ~24 mm recorded in the first 9 days after the PSPE application. The in-crop application was applied at a crop stage of 2-4 tillers, 57 days after planting (57 DAP) and received ~11mm of rain the following day.
A total of 175mm was received during the 5-month duration of the trial. Monthly totals of less than 10mm of rain were recorded in August and September with a total of ~65mm in October.
Wheat establishment was assessed at 18 DAP with ~104 pl