• It’s wet! Spray Application and blackgrass programmes current advice
• Grassweed Control in Winter Field Beans
• Control of Volunteer Beans in cereals
• Aphid Resistance
• Supporting Young Advocates In Agriculture
• This editions FAQs:
  • How efficacious is Kerb Flo 500 on ryegrass? 
  • What weeds does Galera* control? 
  • What are the changes to Dow Shield 400 approvals? 

Autumn 2012 is a challenge......

Some have abandoned the drill and changed their rotation to spring cropping. Many oilseed rape crops are struggling to get away whilst others show signs of stress - some have been ripped-up. Many are hoping to drill wheat in November. Where cereals have gone in, rain has prevented timely application of pre-emergence grassweed herbicides and wet feet are giving concerns for crop damage even if you can travel.

Optimal weed control will be vital this season in order to maximise yield potential and financial returns from late drilled, backward crops. Seeking value from investment in crop protection products will be a priority. We all want to get it right but what do we do now?

Dow AgroSciences’ blackgrass products have a big part to play in meeting these needs.

Let’s look at options for blackgrass control:

Firstly, let’s look at scenarios for oilseed rape:

So far, it has been a very difficult season for establishing winter oilseed rape and planning an appropriate weed control strategy. However, there will still be opportunities during November and December for treatment of crops with Kerb* Flo 500, which will give growers and agronomists the highest possible control of blackgrass. This is very important for the current oilseed rape crop and, by reducing the blackgrass seed burden, subsequent cereal crops in the rotation.

1.  Crop established. Broadleaved weeds and grassweeds present

It’s already wet and with soil temperature falling it will soon be ideal for applications of Kerb Flo 500 to commence (if you can travel). These criteria are normally met in the main oilseed rape growing areas of the UK during November and December. Sign up for Kerb Weather data for latest advice.

The “best” blackgrass approach, proven by extensive trials, has been to apply Kerb Flo 500 at the correct timing - usually November/December. For additional control, Kerb Flo 500 can be tank mixed with a ‘fop/dim’.  In high populations of “difficult” blackgrass, superior control can be achieved by adding a ‘fop/dim’ to Kerb Flo 500 (even when ‘fop/dim’ resistance is present) over a carbetamide/propyzamide sequence. Kerb Flo 500 is physically and biologically compatible with Laser and oil.

Multi-way tank mixes

Downy mildew and phoma are a concern, prompting questions on multi-way mixes. Many crops have not had planned fungicides as yet. Kerb Flo 500 is physically compatible with many fungicides including:
  Punch C  (sprayable under continuous agitation)
  Plover
  Proline
  Sanction  (sprayable under continuous agitation)

Although many such mixes have been tested and shown to be ‘physically compatible’, we don’t support Kerb Flo 500 + graminicide + fungicide mixes for crop safety reasons, due to the potential for enhanced PGR effects from the fungicide and so use is at growers’ own risk.

Galera* is physically and biologically compatible with Kerb Flo 500.

We have also tested a number of insecticides. Download tank mixes with Kerb Flo 500 

Dense Canopies and Spraying Kerb Flo 500

Current soil conditions may limit application opportunities in the next few weeks and if you are in a fortunate position to have a well-established crop you may be concerned the canopy will impair herbicide performance.

Oilseed rape Canopy Trial - December 2011

To ensure our advice is current and correct and in response to concerns last season about the efficacy of Kerb Flo against denser than average crop canopies, trials were conducted in Europe to identify the impact of fuller crop canopies on propyzamide efficacy.

Applications were made at two timings; the earlier timing was applied to crops with intact canopies whilst the later timing was applied to plots where the canopy remained intact or to plots where the canopy was removed. 

Results confirmed no difference in blackgrass control between plots where the canopy was intact and where the canopy was removed and therefore where crop canopies are dense going into winter, propyzamide was still just as effective. Waiting for optimal timing based on soil temperatures of <10°C and soil moisture deficit of <50mm is still the best approach regardless of crop canopy size.

2.  Crop establishment very poor. Broadleaved weeds and grassweeds emerging
Many crops are yet to grow much beyond the two to four leaf stage.

Crop selectivity for propyzamide is by depth protection of the roots. Applications to very small oilseed rape plants can cause problems; stunted growth with leaves fused to the axil or stem, yield depression. Once a crop has reached the three true leaf stage the roots are at sufficient depth to not take up a dose of propyzamide that could cause problems.

Some are considering options of either applying a low dose of carbetamide now in an effort to get some effect on emerging blackgrass and following up with Kerb Flo 500 later to achieve acceptable levels of blackgrass control OR applying a tank mix of Kerb Flo 500 with carbetamide in November or December.

Early treatment with low doses of carbetamide risks damaging small oilseed rape plants. With low crop plant populations this year, the last course of action an agronomist or grower will want to take is to jeopardise the survival of the plants that have established. The correct approach is to control volunteer cereals early with an approved graminicide, then follow with Kerb Flo 500 + Laser + Oil at the optimal timing.

Dow AgroSciences does not support the carbetamide + propyzamide tank mix approach for the following reasons:

• We are not able or willing to indemnify the performance of a third party product for control of blackgrass (this applies to all mixtures of propyzamide and carbetamide, but particularly where the total dose of products applied does not exceed 100%).
• We will not support "overloading" of active ingredient due to our position on water stewardship and the potential for both these active ingredients to reach water (this applies where the total dose of propyzamide and carbetamide exceeds 100%).
• Mixes of propyzamide and carbetamide do not perform as well or as consistently as Kerb Flo 500 + Laser + oil and the degree of variability in performance is much higher.

Thinking ahead to later this year, Kerb Flo 500 may be applied in frosty conditions but do avoid application onto frozen ground where subsequent rainfall could result in run-off into water–courses.

And now scenarios for controlling blackgrass in winter wheat:

1. Crops yet to be drilled

The “optimum” blackgrass programme is still an option here – a pre-emergence application of  flufenacet containing product, followed by an autumn application of UNITE *

2. Crops where pre-emergence has been missed

A peri-emergence application flufenacet containing product, followed by an autumn application of UNITE

3. Crops where pre/peri-emergence has been missed

We are receiving many enquiries about tank mixing the “pre-emergence” with UNITE  and applying it as a post emergence treatment. In previous, more clement autumns we have found these mixes to be physically and biologically compatible but would counsel caution with current conditions of stressed, backward crops.

This is our best advice for this scenario:

UNITE – Applied in a tank mix with the pre-emergence herbicide

**A dose rate of 240g ai/ha flufenacet is compatible with UNITE - BUT WATCH OUT FOR STRESSED CROPS.

Please note options for scenarios 2 and 3 above represent practical approaches in  response the difficult conditions being experienced on farms this autumn and are a compromise on the advice for “optimum” control  given in  scenario 1.

Use as part of a programme and follow WRAG guidelines.

FPU – Apply it as UNITE!!

Applying FPU in formulation with pyroxsulam as UNITE brings the following benefits:

• Get the FULL benefit of both its contact and its residual activity
• Prolonged residuality:
  • Soil temperature of 20°C half life = 26 days
  • Soil temperature of 10°C half life = 58 days = 2 x the residuality
• Get the benefit of its contact activity on broad leaved weeds
• Maintain the flexibility to follow up with an ALS- inhibitor  broad leaved weed product for example for:
      • Cleavers
      • Thistles
      • Poppy
      • Volunteer Potatoes
  It all adds up to more for your money without compromising your blackgrass control!!

RYEGRASS and BROME CONTROL IN WINTER WHEAT

In non-blackgrass situations but where ryegrass, wild oats and brome species are present, Broadway* Star is a highly cost-effective solution offering cross-spectrum weed control. Like UNITE, Broadway Star has the flexibility to be applied in the spring up to GS32. However, trials data has consistently shown that control of ryegrasses and bromes is best achieved in the autumn.

In many regions last year growers noticed higher than average brome populations which has subsequently resulted in a high seed return this year. Dow AgroSciences’ Grassweed Emergence Monitor is watching closely how key grassweed are emerging including brome.

Sign up for Dow AgroSciences’ Grassweed Emergence Monitor

Download the Broadway Star product technical support sheet here.

With no known resistance, Kerb Flo 500 is an ideal solution to blackgrass control across the rotation and can be used in all varieties of winter beans. Kerb Flo 500 should be used pre-emergence at the maximum rate of 1.7 L/ha for the control of all major grassweeds: blackgrass, bromes, wild oats, volunteer cereals and annual meadow grass, as well as key broad-leaved weeds including chickweed. As with Kerb Flo 500 in OSR, applications can only be made between 1st October and 31st January. Applications should be made within seven days of drilling and prior to crop emergence. Damage to the crop may occur if Kerb Flo 500 is applied post-emergence. Growers should also be aware that the nature of seedbed/establishment method can impact on the efficacy. Kerb Flo 500 in winter field beans should be applied to medium or heavy soils (not be used on crops grown in sands, very light soils or light soil types) and growers should ensure a firm clod-free seedbed before spraying.

Kerb Flo 500 can be tank mixed with additional herbicides to enhance the weed spectrum. For more information on this and other aspects of Kerb Flo 500 in beans, download the Kerb Flo 500 technical sheet or go to our website.

Winter beans in the rotation provide a useful break crop and an opportunity to clean up crops. However, volunteer beans can be difficult to control by cultural methods alone, as the large nutrient reserves in the seed allows beans to successfully germinate even after ploughing. Not only are volunteer beans extremely competitive in the crop, they may cause shading of target grassweeds which may reduce their exposure to contact graminicides.

A robust and reliable contact herbicide is crucial and Spitfire* offers the ideal solution for the control of volunteer beans and other broad-leaved weeds in winter wheat, barley, oats and rye. Spitfire can be used in all varieties from GS 13.

Spitfire Rate	Bean Growth Stage	Key Benefits
0.5 L/ha + adjuvant1	Up to 4 etl	Use from GS 13 Excellent tank mix flexibility with: Autumn graminicides Autumn residuals BYDV insecticides Does not add to DFF loading Rainfast in 1 hour
0.75 L/ha	Up to 4 etl
0.75 L/ha + adjuvant1	Up to 6 etl
1  MSO Adjuvant (Toil, Phase II, Rigger) OR - Respond, Kantor, Bio Syl, Spryte Aqua Key: etl = established true leaves

The autumn maximum rate of Spitfire is 0.75 L/ha. The addition of an adjuvant will enhance the activity of Spitfire when tackling larger volunteers.  See above for additional information on rates and supported adjuvants. Spitfire is also compatible with many other autumn sprays including autumn graminicides, residuals and BYDV insecticides, a crucial advantage when autumn weather frequently limits spay days.

In situations where a spring flush of weeds is expected, Spitfire used in the autumn still gives flexibility in the spring for a florasulam follow up and will still only count as one ALS-inhibitor treatment. Remember that you can apply a maximum of two ALS-inhibitor products per crop (only one for grassweed control) but where florasulam is one of your ALS-inhibitor products, an additional application of florasulam can still be made providing the total dose does not exceed 7.5 gai/ha/crop.

For more information about autumn use of Spitfire, download the Spitfire technical sheet here.

After last season’s identification of pyrethroid resistant aphids in the eastern counties, growers may find themselves looking for alternative solutions to the management of BYDV vectors this autumn. Pyrethroid resistance has been identified in the grain aphid Sitobian avenae. Although BYDV is transmissible by both grain aphid and bird cherry-oat aphid, it is the latter that is considered the major vector. However, if growers know they have resistant aphids, Dursban* WG can be used as an autumn foliar insecticide at a rate of 1.0 kg/ha (a maximum of two 1.0 kg/ha applications can be made prior to GS 39) although there are no label recommendations. If resistance is not confirmed, an approved aphicide at the full label rate may be a more suitable option and will allow for the use of Dursban WG later in the season for control of wheat bulb fly and OWBM populations.

A guideline publication has been released by the Insecticide Resistance Action Group UK and can be found on the CRD website: Click Here

Be aware that Dursban WG should not be tank mixed with ALS-inhibitor cereal graminicides. A 14 day interval should be observed between applications of Dursban WG and UNITE and Broadway Star. A 28 day interval should be observed between applications of Dursban WG and formulations of iodosulfuron-methyl-sodium and mesosulfuron-methyl.

On 4th October at The Farmers & Fletchers Livery Hall in London, a group of Young Advocates for Agriculture went head to head debating key issues in contemporary farming at an event where Dow AgroSciences were key sponsors.

After four debates, including such heated topics as GM crops, family farms and single farm payments, the winning team were Sarah Allison and Scott Somerville from the Scottish Agricultural College who successfully debated against the notion that large scale livestock systems lead to poor animal welfare. The winners received an impressive trophy presented by Her Royal Highness The Princess Royal, who gave a fantastic speech to close the event; “From science and technology and all the skills in between...there are so many opportunities.”

Scott Somerville and Jake Pickering were awarded an additional prize as the Oxford Farming Conference Council invited the best two individual debaters to act as seconds in the prestigious Oxford Farming Conference Debate taking place in January 2013.

Q. How efficacious is Kerb Flo 500 on ryegrass?

A. Although ryegrass is not on the label for Kerb Flo 500, trials data and field results have shown propyzamide to have good activity against both Italian and perennial ryegrasses.

Q. What weeds does Galera control?

A. Galera can be applied to all varieties of winter oilseed rape from the 4 leaf stage of the crop and will control a range of competitive broad-leaved weeds including cleavers, mayweeds and sow-thistle.

For a more comprehensive weed list see the table below.

Key: Label weeds are shown in italics
** Best suppression of cleavers will be achieved in the spring

Q. What are the changes to Dow Shield 400 approvals?

A. Dow Shield 400 has now been given approval for use on linseed, broccoli/calabrese, cabbage and cauliflower. Download updated label.

Subscribing to Dow AgroSciences' Agronomy Update & Pestwatch gives eligibility for 1 Crop Protection BASIS Points annually. Please include course name "Agronomy Update & Pestwatch" and the number "CP/24531/1213/g" on your training record. These details apply until 31st May 2013.

If you require any further information please contact our technical Hotline on 0800 689 8899 or your local Dow AgroSciences representative.

Dow AgroSciences supports the safety and efficacy of its products for tank mixes shown as Physically and Biologically Compatible, but does not warrant the efficacy of other tank mix partners.

Use plant protection products safely.  Always read the label and product information before use.
For further information including warning phrases please refer to the product label.

* Broadway, Dursban, Galera, Kerb, Spitfire and UNITE are trademarks of Dow AgroSciences LLC.
^† Dow Shield is a trademark of the Dow Chemical Company
All other brand names are trademarks of other manufacturers for which proprietary rights may exist.

Broadway Star contains pyroxsulam and florasulam
Dow Shield contains clopyralid
Dursban WG contains chlorpyrifos
Galera contains clopyralid and picloram
Kerb Flo 500 contains propyzamide
Spitfire contains fluroxypyr and florasulam
UNITE contains pyroxsulam and flupyrsulfuron-methyl-sodium

More information can be found at www.dowagro.com/uk