A Thank You ...

Broad-leaved weed flush on new grass leys 

How do you control powdery mildew in sugar beet with Fortress?

Fazor - a cost effective ICM tool

Dock control in silage aftermaths

This edition's FAQs:

- How late can I use Dow Shield on forage maize?

- Can I use Dow Shield on game cover?

- Which Dow AgroSciences grassland products can I use through a weed-wiper?

Thank you to those who visited our stand at Cereals 2011, saw the Spitfire and who donated to fund-raising on behalf of the Royal Air Force Association, a charity which cares for airmen and women. Your generosity meant a significant sum of money was raised for this worthy charity. Thanks also goes to the RAFA volunteers who called up a Douglas DC3 transport aircraft from the Battle of Britain flight to overfly the stand and pay homage to the Spitfire below. We hope you enjoyed the show!

Recent rains and showers have saved the establishment of many spring-drilled leys but have resulted in a flush of newly emerged broad-leaved weeds.

Product choice on new leys is restricted, but both Pastor* and Doxstar* have recommendations. A new ley is considered to be grassland less than 12 months old. Both products are safe to grassland from the 3-leaf stage.
 
Doxstar has recommendations for control of common chickweed and seedling docks from the 2 leaf stage up to 50mm across at 1.5 L/ha in 200 litres of water.

Where a broader spectrum of weeds is present Pastor should be used at 2.0 L/ha in 200 litres of water from 2-leaf stage of broadleaved weed. Label weeds include:

Key: etl = established true leaves

Where there is a large reservoir of seedling docks in the soil, a further application in the following year may be required.

In addition to the above there are a number of non-label weeds which Pastor has strong activity on. These include:

Key:  etl = established true leaves

and many more ....

A common situation is where large perennial weeds have survived the establishment of the ley and are competing with the crop. Control of these weeds is unlikely to be sufficient with the rates permitted on new leys and longer term approaches measures in addition to the above, must be considered once the grass is established after 12 months. 

Both Doxstar and Pastor are rain fast within 2 hours if applied to a dry leaf.

Learn more about Doxstar

Achieve up to 8 weeks control of powdery mildew (Erysiphe betae) in sugar beet.

According to BBRO, powdery mildew remains the main threat to productivity.  Early protection of the valuable sugar beet crop is essential to ensure losses from this fungal infection are minimised, which usually is found in the crop from mid-July onwards.

The infection can be identified by white/grey fungal mycelia and spore growth on the leaf surfaces. Over a period of time this fungal growth will turn the leaves yellow and cause them to die back - resulting in a reduction in green leaf area, sugar content and yield.

Fortress* (quinoxyfen) can be used in sugar beet at 0.3 L/ha or, alternatively, as a split treatment of two applications at 0.2 L/ha. The sequential approach may be beneficial where high and sustained levels of powdery mildew are expected, where re-infestation is expected or where a later harvest is planned.

Fortress should be applied at the first sign of disease which is usually mid July or early August. Where the split treatment is used, a further application can be made any time up to 28 days before harvest.

Using Fortress means that growers can benefit from a proven product that has a unique mode of action and can offer up to 8 weeks protection.

Learn more about powdery mildew in sugar beet 

Download literature and labels for Fortress 

Fazor^† provides suppression of volunteer potatoes and sprouting in store. In addition, BPC work has demonstrated that Fazor can save up to 2 applications of CIPC. Fazor is cost-effective. 

What is the optimum time to apply Fazor?

What is the condition of the haulm?
Overall the haulm should be in good condition, actively growing and free from pest and disease. A few of the lowest leaves may be turning yellow, but the haulm should be predominantly green.

Sample dig potato plants across the field.
Put sample tubers through a 25mm hole. If the tubers fit through the hole, then it is probably too early to apply Fazor, if so - check the tuber size again in a week.

When do you want to lift the potatoes?
Fazor should be applied 3-5 weeks before haulm destruction. Application 5 weeks before haulm destruction has been shown to give better sprout control than the later timing of 3 weeks.

Why Use Fazor?

• Applied directly to the crop using a conventional sprayer – no additional investment in machinery
• Fazor has no interval restriction for consumption or processing – potatoes can be sold anytime after lifting
• A single application suppresses both sprouting in store and volunteer potatoes – helps maximise farm workload efficiencies and reduce chemical inputs
• Reduces volunteer potato infestations – minimises the threat of pest and disease carryover, varietal contamination and rented land can be returned in good condition

For maximum uptake and translocation of Fazor:

APPLY Fazor at 5kg/ha on its own in 350-500 L/ha of water.
DO NOT APPLY Fazor if the potato crop is under stress.
DO NOT TANK MIX with tin based or fluazinam fungicides (copper-based or strongly alkaline).
DO NOT IRRIGATE within 24 hours of application.

Learn more about sprout suppression

Learn more about Fazor

Perennial weeds such as docks can significantly affect both the quantity and quality of grass harvested, so well-timed herbicide applications on silage aftermaths can reap rewards for the rest of the season and even into the next spring. This is likely to be particularly so this year with recent rainfall helping to stimulate weed growth.

Docks are bad news in grassland as they:

• Compete for light, nutrients and moisture. Trials have shown that a 10% infestation of docks will cause 10% loss of grass; equivalent to one trailer load of silage in ten
• Are unpalatable with only 65% of feed value of grass.
• Adversely affect silage fermentation which reduces feed quality still further

• Docks are a formidable foe, with an estimated 15% of productive grassland infested and a potential seed bank of 12.5 million seeds/ha in the top 15cm of soil.

Most herbicide applications to silage ground occur prior to or just after first-cut, but recent conditions favouring grass and weed growth may present further opportunity to control this weed in the aftermaths.

Leave the aftermath for two to three weeks to allow sufficient re-growth before spraying. Treat weeds at the rosette stage, when they are actively growing.  This will give good control as weeds will be at a uniform stage of development

Summary

• Assess remaining weed populations where a silage  cut has been taken
• Where treatment is necessary, make applications at the rosette stage of growth
• Weeds must be actively growing to achieve best results
• 7 day stock exclusion period
• 28 day cutting interval
• Excellent grass safety from all products and will not inhibit grass growth after application

Review Critical Success Factors for further information and guidance

Learn more about docks

Learn more about Doxstar

How late can I use Dow Shield on forage maize?

The latest harvest interval for use is 6 weeks pre-harvest interval. The recommendations for control of creeping thistle are 0.5 L/ha at the rosette stage, followed by a second application of 1.0 L/ha three to four weeks later in 200 to 250 litres of water per hectare.

Practically the ability to travel through the crop will limit late use.

Physical compatibilities with Dow Shield^# include:  Samson Extra
(N.B.  This product has not been tested for crop safety in tank mix with Dow Shield)

Always add Dow Shield to the tank last.

Can I use Dow Shield on game cover?

There is a Specific Off-label Approval for Canary grass, Quinoa, Sweet clover (including white melilot, bokhara clover and melilotus alba), Tanka Millet and White Millet grown for game cover.

More details available on CRD web site.

Which Dow AgroSciences grassland products can I use through a weed-wiper?

There are Specific Off-label Approvals for the use of Grazon* 90 and Dow Shield through weed-wipers.

More details available on CRD web site 

Subscribing to Dow AgroSciences' Agronomy Update & Pestwatch gives eligibility for 1 Crop Protection BASIS Points annually. Please include course name "Agronomy Update & Pestwatch" and number "CP/19948/1112/g" on your training record. These details apply until 31st May 2012.

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

Use plant protection products safely.  Always read the label and product information before use.

*Doxstar, Grazon, Fortress, Pastor, are trademarks of Dow AgroSciences LLC.
^# Dow Shield is a trademark of the Dow Chemical Company
^† Fazor is a trademark of Chemtura

All other brand names are trademarks of other manufacturers for which proprietary rights may exist.

Doxstar contains triclopyr and fluroxypyr
Dow Shield contains clopyralid
Grazon 90 contains clopyralid and triclopyr
Fazor contains the potassium salt of maleic hydrazide
Fortress contains quinoxyfen
Pastor contains clopyralid, fluroxypyr and triclopyr

More info at www.dowagro.com/uk