Applying Dow AgroSciences' guidelines for maximising the efficacy of Kerb Flo could make all the difference when controlling black-grass and other grass-weeds 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 this autumn and winter.
Kerb Flo 10 Point Plan
Kerb Flo performance is best when the crop has been established using min-till techniques. Black-grass seed germinating from below the area of the soil profile in which propyzamide is most active, which is the top 5 centimetres, is likely to be poorly controlled.
Applications of Kerb Flo work best when applied to a firm, clod-free seedbed.
Weeds are best controlled when they are small and their roots are close to the soil surface.
Applications of Kerb Flo should be made when soils are moist, but not waterlogged or saturated. A rough guide is 80% field capacity, but before drains are flowing. This will prevent accidental run-off. All care must be taken to avoid any risk to contamination to waterways and all aspects of good Stewardship applied, particularly this year when ground conditions are wet in many parts of the country.
Applications are best made when soil temperatures are declining, with the target optimum temperature of 10°C and falling and weeds are growing slowly. Kerb Flo is less effective in warmer soils. Applications can be made under frosty conditions, but run-off from the soil surface must be avoided.
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 black-grass, in known or expected resistance situations, or when anticipating a protracted weed germination period.
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 of the crop to expose the soil to a direct application and so allow even distribution of the herbicide.
Kerb Flo has a wide window of application right up until the end of January. Later applications (in January) are effective because grass-weeds develop adventitious roots that pick up sufficient active ingredient. Best results are achieved when growth of weeds, especially black-grass and volunteer cereals, is slow but transpiration continues.
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. Make sure you use a Dow AgroSciences- manufactured propyzamide such as Kerb which has been formulated to be easily tank-mixable and is indemnified for a wide range of compatibilities with commonly used partners. Details of Kerb Flo tank mix compatibilities can be found on the web site at www.dowagro.com/uk.
Finally, the crop must have a minimum of 3 true leaves before applying Kerb Flo.
Kerb Flo also has recommendations on Winter Beans on medium to heavy soils with <10% organic matter. Use pre-emergence with 7 days of drilling at 2.1l/ha.
For further information, please contact Rene Pollak, Dow AgroSciences on 07885 662395 (mobile) or via the Dow Technical Hotline on 0800 689 8899.
