Why should I use Adhere with residual herbicides this autumn?
The theory of marginal gains is often applied to how you improve and optimise efficacy from pre-emergence residual herbicides. Seed bed preparation, application technology, product choice, and weather conditions all play a crucial role if small gains are made. However, there is always an element of compromise as seedbeds are often less than ideal and spray days limited. With high blackgrass seed dormancy levels likely in the UK due to the cooler, wetter summer, effective pre-emergence residual herbicide applications will be key to effective weed control this autumn.
For best performance Adhere has proven drift control, it offers even coverage across the soil and increased adsorption of your chosen herbicide onto the individual soil particles. Adhere keeps your herbicide firmly in the upper soil layer to improve control of blackgrass and other weeds. Adhere is a biodegradable, non-hazardous, environmentally friendly adjuvant, derived from renewable resources for use with residual herbicides pre and post-emergence. Adhere contains a blend of fatty acid methyl esters combined with rosin and resin esters and emulsifiers.
Pre-emergence sprays are particularly affected by spray drift as turbulence under the spray boom results in uneven coverage. By reducing the number of spray droplets under 100 microns, Adhere decreases spray drift, ensuring even spray deposition over the soil. Adhere is more effective at reducing spray drift than paraffinic oils. The rosin and resin esters (a new adjuvant class) are tackifiers which stick and increase herbicide adsorption onto soil particles, reducing leaching through the soil, which ensures the active ingredients remain in the upper soil layer where weeds germinate.
The graph above demonstrates Adhere’s ability to reduce the number of spray droplets under 100 microns. When Liberator was applied alone, 15.7% of the spray droplets were below 100 microns. This reduced to 11.5% when a competitor standard paraffinic oil was applied in combination with Liberator. However, Adhere at 0.2l/ha was significantly more effective than the paraffinic oil at reducing the number of spray droplets, with 10.1% under 100 microns.
An independent trial conducted by FieldArm demonstrated how Adhere improves the efficacy of pre and peri-emergence herbicides. The blackgrass population was reduced from 259 heads/m2 (untreated) to 6.5 heads/m2 when Luxinum Plus + PDM + DFF followed by System 50 + PDM was applied. However, when Adhere was included at 0.2l/ha in the tank mix, blackgrass population was reduced to just 0.3 heads/m2. The extent of Adhere trials conducted between 2020 and 2024 can be seen below. The graph shows the percentage blackgrass control when Luxinum Plus + PDM + DFF is applied with or without Adhere. The results show on average across the 18 trials, Adhere increased control by 4%. For example, a 4% improvement in control would represent a reduction of 8 heads/m2 where the background untreated population is 200 heads/m2. With each head capable of producing 100 seeds per head, that prevents 800 seeds/m2 being returned to the seed bank which could be viable for 1-5 years.
In summary, Adhere effectively reduces the number of spray droplets under 100 microns, reducing spray drift and ensuring even spray deposition over the soil. Across 18 trials, on average the inclusion of Adhere increased herbicide efficacy by 4%. It contains a new class of adjuvants called rosin and resin esters that increase adsorption of the herbicide onto soil particles and Adhere should be applied at 0.2l/ha, added to the spray tank last.
