Pesticide usage in Scotland: arable crops and potato stores 2020

Executive summary

This report presents information from a survey of pesticide use on arable crops grown in Scotland. The survey period covers the 2020 growing season, from post-harvest pesticide applications in 2019 through to harvest in 2020. The crop groups surveyed included cereals, oilseed rape, potatoes and legumes.

The estimated area of arable crops grown in Scotland in 2020 was ca. 496,600 hectares. Spring barley accounted for 52 per cent of the arable crop area, wheat 19 per cent, winter barley nine per cent, oilseed rape and potatoes six per cent and spring oats five per cent. Legumes, winter oats and winter rye together accounted for the remaining three per cent.

Data were collected from a total of 312 holdings, representing eight per cent of the total arable crop area grown in Scotland. Ratio raising was used to produce estimates of national pesticide use from the sampled data.

The estimated total area of arable crops treated with a pesticide formulation was ca. 4,793,000 hectares (± three per cent Relative Standard Error, RSE) with a combined weight of ca. 1,370 tonnes (± four per cent RSE). Overall, pesticides were applied to 99 per cent of the arable crop area. Herbicides/ desiccants were applied to 98 per cent of the crop area, fungicides to 96 per cent, growth regulators to 52 per cent, insecticides to 20 per cent and molluscicides to nine per cent. Pesticide treatments were applied to 90 per cent of seed in this survey.

Overall, use of pesticides in 2020 has remained broadly similar to the previous two arable surveys. Taking into account changes in crop area, the 2020 total pesticide treated area was two per cent higher than that reported in 2018 and two per cent lower than 2016. The weight of pesticide applied to arable crops in 2020 was three per cent higher than in 2018 and eight per cent lower than 2016.

Fungicide and herbicide/desiccant use by both area treated and weight applied remained similar to 2018 levels. The area treated with insecticides/nematicides decreased by three per cent from 2018, while the weight applied increased by 17 per cent. Molluscicide use increased 16 and four per cent by area treated and by weight respectively when compared to 2018. While seed treatment use increased six per cent by area treated, the weight applied decreased twenty-six per cent from 2018. The area treated in 2020 with growth regulators increased 10 per cent while there was no change in the weight applied from 2018 levels.

In terms of area treated, the most commonly used foliar fungicide active substance and the most used seed treatment was prothioconazole. The most used herbicide and insecticide was thifensulfuron-methyl and lambda-cyhalothrin respectively. The herbicide aclonifen, the fungicide mefentrifluconazole, the insecticide spirotetramat and seed treatments Bacillus amyloliquefaciens strain MBI600 and penflufen were recorded for the first time in this survey.

Data collected from growers about their Integrated Pest Management (IPM) activities showed that growers were using a variety of IPM methods in relation to risk management, pest monitoring and pest control. This dataset is the second in this series of surveys of IPM measures on arable crops, allowing the adoption of IPM techniques to be monitored.