Oilseed Rape


   

 RELATED LINKS

 

 

 

Learn more about Kerb Flo

 

 

Follow the KERB 10 Point Plan to maximise efficacy in winter oilseed rape

Following Dow AgroSciences' guidelines for maximising the efficacy of Kerb* Flo could make all the difference when controlling blackgrass and other grassweeds in winter oilseed rape. Dow AgroSciences have developed a Kerb Flo 10 Point Plan to help growers and advisors maximise its performance in oilseed rape crops.

Kerb Flo 10 Point Plan:

  1. Kerb Flo performance is best when the crop has been established using min-till techniques.
  2. Applications of Kerb Flo work best when applied to a firm, clod-free seedbed.
  3. Weeds are best controlled when they are small and their roots are close to the soil surface.
  4. Applications of Kerb Flo should be made when soils are moist, but not waterlogged. A rough guide is 80% field capacity, but before drains are flowing. This will prevent accidental run-off.
  5. Applications are best made when soil temperatures are declining. Target temperature is 10°C and falling. Kerb Flo is less effective in warmer soils.
  6. There is dose rate flexibility. Look to the label for more details. Consider using the full rate of 2.1 l/ha when tackling high populations of blackgrass, in known or expected resistance situations, or when anticipating a protracted weed germination period.
  7. Well established crops may hinder an even application of Kerb Flo across the soil surface. In such situations it may be prudent to wait for some winter die-back to expose the soil to a direct application.
  8. Kerb Flo has a wide window of application. Later applications (January) are effective because grassweeds develop adventitious roots that pick up sufficient active ingredient.
  9. Kerb Flo can be mixed with a wide selection of tank-mix partners. Mixing or sequencing with contact graminicides such as cycloxydim has been shown to further enhance weed control.
  10. Finally, especially in a season of difficult establishment, wait until the crop has a minimum of 3 true leaves before applying Kerb Flo.

 

Blackgrass is an extremely competitive weed in combinable crops. Oilseed rape presents a great opportunity to tackle this most pernicious weed by using an active ingredient that has a unique mode of action with no known resistance - propyzamide. Kerb Flo contains 400g/litre of propyzamide in a liquid formulation.

Menace* 80EDF also contain propyzamide.

Many years of commercial experience and extensive trials work confirms the highest levels of control of blackgrass are achieved when seedbed preparations are by minimal cultivations. Kerb Flo performance is not compromised, even when high levels of organic material (straw, chaff) are left on the soil surface, e.g. after establishment by broadcasting seed on the soil surface. Blackgrass seed germinating from below the area of the soil profile in which propyzamide is most active - the top 5cm - is likely to be poorly controlled.

Applications of Kerb Flo to winter oilseed rape can be made between the beginning of October and the end of January, once the crop is evenly established and has reached at least the three true leaf stage. To maximise the efficacy of Kerb Flo soils must be moist to enable successful root uptake by the target weeds. Best residual activity, and hence results, is achieved from applications to moist soils of fine tilth. Applications can be made under frosty conditions, but run-off from the soil surface must be avoided.

 

Best results are achieved when growth of weeds, especially blackgrass and volunteer cereals, is slow but transpiration continues. In mild autumns and winters emerged weeds may take longer to be controlled, the residual effect will be shortened and overall control may be reduced. Optimal conditions, that allow Kerb Flo to perform at its best, do not normally occur until early November.

There is currently no known strain of blackgrass, or any other grassweed, exhibiting any degree of resistance to propyzamide.

 

 

Summary

  • The optimal timing for applications of Kerb Flo is November
  • Even late-drilled crops will have reached the minimum three true leaf stage by then
  • Blackgrass seed will germinate and emerge over an extended period this year
  • The activity of propyzamide, the active ingredient in Kerb Flo, is maximised under cooler soil conditions, i.e. from November onwards
  • Propyzamide is a residual herbicide with root uptake that requires even distribution in the soil profile
  • Where crops have a well-established canopy, wait until winter die-back has started, to allow applications to reach the soil surface
  • Applications should be made to firm, moist soils with a fine tilth
  • Applications must be made to small blackgrass plants, before they tiller
  • Increased rates should be used under warm autumn/winter conditions
  • Increased rates should be used where blackgrass resistance has been confirmed
  • Strategic use is recommended in tank mix or sequence with graminicides

Visit the following product pages for more comprehensive information about Kerb Flo, and Menace 80EDF.

Find out more about Oilseed rape herbicides and water protection