Arable Update – October 2016

TP21869 Arable Update Newsletter header

In this Edition

  • Brome identification
  • Volunteer bean and volunteer oilseed rape control
  • Preventing nitrogen leaching during fluctuating weather patterns
  • Time your oilseed rape treatment to perfection
  • Canopy size and Kerb

Brome Identification

For UK arable farmers, brome grasses continue to be some of the most pernicious and difficult weeds to control. In the UK, there are five species of brome which occur as arable weeds. To maximize successful control you need to identify the species present, and time applications accordingly depending on whether they are autumn or sprbrome-in-wheating germinators. To help identify which species you are tackling you should refer to the joint Dow AgroSciences/Rothamsted Research – Know your brome guide.

Broadway® Star, the market leader for over half a decade, provides the most robust and consistent option for effective long term brome control.

Autumn application of Broadway Star for autumn germinating bromes (great & sterile brome) has been shown to consistently deliver the best results. If this autumn is as mild as last year, the advice is to apply Broadway Star in the autumn.

Broadway Star is much more than just a graminicide as it provides control of many broad-leaved weeds such as speedwells, volunteer oilseed rape and beans, chickweed, cranesbill and cleavers, all of which readily germinate in the autumn.

Volunteer bean and oilseed rape control

winter bean volunteers in WWSpitfire® still represents the best option for volunteer bean and oilseed rape control this autumn. With its unique formulation, Spitfire delivers consistent, robust control of volunteers, whilst using a lower dose of florasulam than other formulations on the market leaving you with ALS flexibility in the spring. Also, it does not contain DFF, giving you flexibility with your autumn residual programme and following crop options.

Spitfire is LERAP B, meaning it has a reducible buffer zone as long as the LERAP requirements are met. This means that you can spray all parts of the field giving you complete control, unlike some of the options currently on the market.

Spitfire can be used at 0.5l/ha + Methylated Seed Oil adjuvant on volunteer beans up to 4 true leaves, providing complete control even in fluctuating temperatures. For larger weeds the rate can be increased up to a maximum of 0.75l/ha in the autumn.

Spitfire has a further advantage of having the largest broad-leaved weed spectrum of autumn applied broad leaved weed herbicide options. Giving robust control of many weeds including cleavers. Spitfire will control the most yield robbing and unsightly weeds in winter cereals.

Preventing nitrogen leaching during fluctuating weather patterns

From one of the wettest Junes in recent years to one of the driest Augusts on record our weather across many parts of the country has delivered challenging conditions for a wide range of crops. With these fluctuations in our weather patterns crop husbandry becomes even more challenging.

corn_n-lockThis year Dow AgroSciences conducted field scale trials with N-LockTM, our nitrogen stabiliser product, with different fertiliser application regimes on a crop of feed wheat in Norfolk. A total of 260kg N/ha was applied either in one application, two application or three applications. N-Lock was applied across all plots at the start of spring. Throughout the growing season no visible differences could be observed and the plot which received all of its nitrogen in mid- March did not fall over! The plots were harvested in mid-August with less than a 2% difference in yield across them all. This work helps build data showing N-Lock protects nitrogen from moving away / leaching from crop roots and helping to manage the busy spring workload on farms by allowing one or two fertiliser applications to be dropped without having a potential yield penalty.

Maize harvesting is in full swing, slightly later than a “normal” year, again due to weather, especially temperature fluctuations and a very wet June. N-Lock treated and untreated plots are being harvested. The photo shows the cob samples from one field in Suffolk. As shown the treated samples have consistently larger cobs, this has been seen in other crops across the region this year. The fresh weight N-Lock plot yield at this site was over 11% more than the untreated plot.

N-Lock is showing again this year that keeping nitrogen in the rooting zone for longer optimises yield and protects a grower’s fertiliser investment.

Time your oilseed rape treatment to perfection

Kerb® Flo 500 and ASTROKerb® dominate the weed control market in winter oilseed rape. It is not surprising given the successful experience of thousands of growers over millions of acres treated over decades.

However, making the most of these products depends on good establishment and the right weather and soil conditions. That means moist soils with a firm tilth and soil temperature below 10°C at 30cm depth.

If this sounds a bit too complex, then let Dow AgroSciences postcode checker help you.

This online tool can be found at you need do is enter your postcode and check the ‘traffic light’ display.

Red = wait
Amber = get ready
Green = time to take action

It really could not be simpler.

If the autumn stays mild, don’t panic as you have until 31st January to apply either of these products. The traffic light system is not a definitive go/don’t go but a tool to advise a farmer or agronomist that conditions are coming right to apply or perhaps a prompt to investigate more thoroughly the timing of an application on a particular farm or field.

And before you spray, be sure to take note of the Voluntary Initiative guidelines on ensuring oilseed rape herbicides do not enter water courses. In particular, do not spray when drains are running or when rain is forecast within 48 hours. This is vital advice to preserve access to the most effective active ingredient in the oilseed rape growers’ armoury.

Large Canopies and Kerb Application

Trials have shown that even where canopies are dense, excellent blackgrass control can be achieved once optimum soil conditions are met.

Outlined below are the results of a trial in Essex to investigate the efficacy of Kerb Flo 500 on blackgrass in oilseed rape when applied with an intact crop canopy or with the crop canopy removed. Kerb Flo 500 was applied at two different timings, an early timing, sprayed on 26th November 2015, and a later timing which was applied on 4th January 2016. The crop canopy was either left intact or removed prior to spray application.

Product: Kerb Flo 500
@ 1.7 L/ha
Crop drilled: 19 August 2015
@ 5.0 kg/ha
Variety: Picto
Spray timing A: 26 Nov 2015 Crop BBCH 17-19 (canopy
intact treatment)
Blackgrass BBCH 14-21
Spray timing B: 4 Jan 2016 Crop BBCH 11-19 (canopy
intact treatment)
Blackgrass BBCH 15-25


OSR Canopy Removal Trial – UK 2015


Spray timing A: 26 November 2015, blackgrass GS 14-21
Spray timing B:  4 January 2016, blackgrass GS 15-25

Canopy Removal Conclusions

  • A full oilseed rape crop canopy at time of application makes no difference to final levels of blackgrass control when using Kerb Flo 500
  • Waiting for optimal soil conditions, i.e. soil temperature at 30cm is <10oC and declining and soils are moist, is still the correct approach, regardless of ground cover from a well-developed crop canopy
  • The latest field-based research data proves our advice remains current, correct and fully effective.

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ASTROKerb contains aminopyralid and propyzamide
Broadway Star contains pyroxsulam and florasulam
Kerb Flo 500 contains propyzamide
N-Lock contains nitrapyrin
Spitfire contains florasulam and fluroxypyr

More information can be found at
Dow AgroSciences Limited, CPC2, Capital Park, Fulbourn, Cambridge, CB21 5XE. Tel: +44 (0) 1462 457272.