Warm soil temperatures and plenty of moisture across the region gave oilseed rape crops the best possible start.
Warm soil temperatures and plenty of moisture across the region gave oilseed rape crops the best possible start. However, as predicted, slugs have been a real menace in some fields, to the extent where some patches have been been redrilled. Flea beetle has been a bit more variable. While the pest has remained absent in some fields, in others it has been a real issue.
Pre-emergence herbicides appear to be working quite well. However, due to the speed of germination, pre-ems were missed in many fields and, as weeds also germinated quickly, post-emergence residuals will really have their work cut out. The addition of the contact herbicide Parish [phenmedipham] to our armoury this season could therefore be useful, particularly in areas where the pre-emergence herbicides have been missed and weeds such as chickweed are already established. While Parish is not a stand-alone herbicide and should always be part of a programme, it really fits in where residuals have either failed, have been missed, or as a precursor to the likes of Clearfield or Kerb [propyzamide], preventing key weeds getting too big and competitive. To get the best activity from Parish on several difficult weeds, it is vital to spray on bright sunny days, when crops are actively growing as it works by inhibiting photosynthesis.
Companion plants in oilseed rape have also established well and the synergy between berseem clover and better rooted oilseed rape can already be clearly seen. As a word of warning, it is worth checking with your seed merchant which variety of berseem clover you drilled as one type was marketed and sold into the industry which is developed for forage and has not been designed as a companion plant for oilseed rape. Not only can this bring in unwanted early competition to the developing oilseed rape crop due to its more prostrate growth habit, but as it is a multi-cut type of clover, it is unlikely to be naturally removed over winter and will require a spring application of clopyralid to control it.
The heavy rain showers in early September played a valuable role in preventing early drilling of cereals. The showers also helped with grass-weed flushes, so stale seedbeds should be effective this year.
With residual herbicides increasing in their importance in the battle against grass-weeds, seedbeds have never been so important. It is vital to get good seed to soil contact but also to ensure the seed is consistently covered with up to 40 mm of soil to minimise crop damage as we stack more residual chemistry pre-emergence. Application is key to get the most out of residual chemistry and it is vital we ‘paint’ the soil. This requires maximising the number of droplets hitting the target and is best achieved with a higher water volume while maintaining as fine a spray quality as practical on the day of spraying.
For many years, using twin lines or twin caps angled forwards and down have consistently performed the best and can be set up quickly on any sprayer for little cost. The addition of an application aid such as Remix is also now essential. Remix can greatly improve the performance, crop safety and environmental impact of residual herbicides. Remix provides three major functions. It firstly reduces drift by optimising spray droplet size, reducing the number of the smallest droplets. It is also able to maintain fan angle across a greater range of pressures ensuring more even deposition. This is particularly important close to headlands where operators usually slow down prior to turning, which can result in narrower fan angles and uneven spray deposition. The unique long polymer chain formulation also gives it a positive charge which allows it to bind to colloids, such as clay particles or organic matter, in the soil keeping the product in the zone of activity for longer, improving performance, reducing crop damage from residual chemistry and minimising leaching into water courses.