Pesticide usage - arable crops and potato stores 2018: survey results

Executive summary

This report presents information from a survey of pesticide use on arable crops grown in Scotland.  The survey period covers the 2018 growing season, from post-harvest pesticide applications in 2017 through to harvest in 2018.  The crop groups surveyed included cereals, oilseed rape, potatoes and legumes.

The estimated area of arable crops grown in Scotland in 2018 was ca. 489,309 hectares.  Spring barley accounted for 51 per cent of the arable crop area, wheat 20 per cent, winter barley eight per cent, winter oilseed rape seven per cent and spring oats five per cent.  Potatoes, legumes, winter oats and winter rye together accounted for the remaining nine per cent.

Data were collected from a total of 315 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. 4,632,066 hectares (± three per cent Relative Standard Error, RSE) with a combined weight of 1,312 tonnes (± three per cent RSE). Overall, pesticides were applied to 98 per cent of the arable crop area. Herbicides/desiccants were applied to 96 per cent of the crop area, fungicides to 93 per cent, growth regulators to 45 per cent, insecticides to 23 per cent and molluscicides to 10 per cent. Pesticide treatments were applied to 84 per cent of seed in this survey.

Taking into account changes in crop area, the 2018 total pesticide treated area was four per cent lower than that reported in 2016 and 2014.  The weight of pesticide applied to arable crops in 2018 was 11 per cent lower than in 2016 and six per cent lower than 2014.  The application of growth regulators, seed treatments, fungicides and herbicides/desiccants in 2018 decreased from the 2016 survey (8, 6, 4 and 2 per cent decreases in treated area respectively).  Only molluscicide use increased between 2016 and 2018 both in terms of treated hectares (ten per cent) and in weight applied (12 per cent). The use of insecticides increased in terms of area treated (3 per cent) although the weight applied decreased by 30 per cent.

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 metsulfuron-methyl and lambda-cyhalothrin respectively.  The herbicide imazosulfuron, the fungicides oxathiapiprolin and benzovindiflupyr and a seed treatment, sedaxane, were recorded for the first time in this survey.