Article taken from Orion Farming Group Newsletter, September 2017.
With bills exceeding £100/ha on some farms for residual herbicides alone, wheat growers need to eke out the best possible performance from their residual chemistry, writes Agrovista technical manager Stewart Woodhead.
Getting this chemistry where it needs to be, and keeping it there, is critical. A high-quality application aid can really help.
Remix, a paraffinic oil made up of long-chain molecules, reduces spray drift and improves the spray pattern. Its long-chain, positively charged molecules also help bind the herbicide active to clay and organic matter, keeping it in the surface layer for longer to optimise weed control.
Trials in 2016/17 at Draughton in Northamptonshire, where levels of difficult-to-control black-grass reach 650 heads/m2, confirmed several year’s results in trials and commercial crops that show how effective Remix can be.
Three large plots of wheat received varying pre-em approaches. One was left untreated, the second received Liberator at 0.6 litres/ha plus an alternative adjuvant at 0.2 litres/ha, while the third received the same dose of Liberator plus Remix at 0.2 litres/ha.
Early post-em regimes were then overlaid on these plots. The first section received nil treatment, the second Avadex (15kg/ha) + Fence (0.25 litres/ha) + Herold (0.3 litres/ha) and the third the same again plus Xerton (0.6 litres/ha).
The Liberator + Remix outperformed the competitor by a clear margin, achieving 65%, 88% and 99% reduction in black-grass seed heads across the three post-em regimes respectively. The competitor figures were 45%, 70% and 80%.
Overall, the results show that good application technique and keeping residual chemistry near the surface is at least as important as increased residual loading.