Welcome to the second edition for this autumn, providing timing guidance for propyzamide applications to oilseed rape.
Soil temperatures (at 30 cms) are becoming cooler, close to 10°C, in northern and central areas. In eastern areas soil temperatures remain too warm (11°C – 12°C) for effective Kerb® Flo 500 and AstroKerb applications. Broadly with temperatures set to stay mild we would expect to see a lot of applications start in around about a week’s time. .
It is important to wait until soil temperatures have cooled to less than 10°C as this optimises the blackgrass control activity from your propyzamide application. Cooler soil temperatures slows propyzamide breakdown and ensures blackgrass roots are exposed to propyzamide for longer periods of time, thus optimizing control.
With recommendations and applications already being made and with rain forecast for parts of the UK for the weekend it is important to remember that there is an increased risk to water if there is heavy rainfall within 48 hours of application to a dry soil, so caution is recommended.
Use the maps and links below to find the data for soil temperatures and moisture-deficits in your region. Please note at 30 cms soil temperature reading is less variable than the more commonly used 10 cm reading.
Welcome to the first edition for this autumn, providing timing guidance for propyzamide applications to oilseed rape.
Overall soil temperatures (at 30 cms) in oilseed rape growing areas are around 11°C – 13°C but falling rapidly due to the recent cold weather, too warm for outstanding results to be achieved with Kerb® Flo 500 or AstroKerb® for blackgrass control. In northern England (and Scotland) soil temperatures are cooler (nearer 10°C) but with milder weather forecast at the weekend soil temperatures are generally sub optimal for effective propyzamide applications. Soils usually become suitable for Kerb Flo 500 and AstroKerb applications around the 10th November based on previous years so we would expect recommendations to be made imminently.
More Kerb Weather Data will be supplied as the season progresses.
After the 1st of October, theoretically you can start applications of propyzamide (such as Kerb Flo 500 and ASTROKerb) in oilseed rape according to their labels, but practically this active ingredient with residual activity, should only be applied when conditions are correct to optimize its performance. For that you need to wait until the soil temperature has gone below 10°C and is still falling and soil moisture is sufficient.
For the 2018 Kerb Weather Data service please click here
Temperature and soil moisture are critical to getting the best performance from Dow AgroSciences’ two leading oilseed rape herbicides – Kerb® Flo 500 and ASTROKerb®. The Dow AgroSciences’ postcode checker as seen here is an online tool that will help decide when it is time to spray. It could not be simpler, type in your postcode and the result appears as a traffic light : Red means wait; Amber means get ready and Green means consider going. It is rare that you will get a green light before November, but as both products can be used up to January 31st, there is no rush.