Pesticide usage: outdoor vegetable crops 2019

Executive summary

This report presents information from a survey of pesticide use on outdoor vegetable crops grown for human consumption in Scotland during 2019. The crops surveyed included vining peas, broad beans, Brussels sprouts, calabrese, carrots, turnips & swedes and other minor vegetable crops.

In 2019 the census area of outdoor vegetable crops grown in Scotland was approximately 18,600 hectares. This represents a four per cent decrease in area from the previous survey in 2017 and a 12 per cent increase from 2015. The principal outdoor vegetable crops grown in Scotland were peas and beans making up 53 per cent of the cropped area. Carrots accounted for 18 per cent, leaf brassicas 16 per cent, turnips and swedes eight per cent and other vegetables five per cent.

Data were collected from a total of 86 holdings, representing 12 per cent of the total vegetable area grown in Scotland. Ratio raising was used to produce estimates of national pesticide usage from sampled data.  The estimated total area of outdoor vegetable crops treated with a pesticide formulation (area grown multiplied by number of treatments) was 176,200 ha (± 5 per cent Relative Standard Error, RSE) with a combined weight of ca. 72.6 tonnes (± 5 per cent RSE).  Overall, pesticides were applied to 96 per cent of the vegetable crop area.  Herbicides were applied to 89 per cent of the crop area, insecticides to 75 per cent, fungicides 82 per cent, molluscicides to 12 per cent and 74 per cent of seed was treated.

Taking into account changes in crop area, the 2019 total pesticide treated area was seven per cent higher than that reported in 2017 and 12 per cent lower than in 2015. The weight of pesticides applied to vegetable crops was 15 per cent higher in 2019 than in 2017, though four per cent less when compared to 2015.  The application of fungicides, insecticides and sulphur have increased since 2017 (19, 13 and 33 per cent increases in treated area respectively).  Minor use of biological control agents and growth regulators were recorded in 2019, but were not recorded in the 2017 survey. The application of seed treatments, herbicides and molluscicides has decreased since 2017 (1, 5 and 14 per cent decreases in treated area respectively).  Overall, pesticide application to vegetable crops was higher in 2019 than in 2017.  However, lower pesticide use in 2017 was influenced by climatic conditions and lower pest pressure.

In terms of area treated, the most used foliar fungicide active substance was azoxystrobin.  Lambda-cyhalothrin and pendimethalin were the most used insecticide and herbicide active substances respectively.  Cymoxanil, fludioxonil and metalaxyl-m, were the most used seed treatment active substances.

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 vegetable crops, allowing the adoption of IPM techniques to be monitored.