Pesticide usage report: Vegetable crops 2004

Summary

This is the fourth survey of pesticide usage on outdoor vegetable crops in Northern Ireland, providing comparative data to that obtained in the previous surveys in 1991, (Jess et al., 1993),1995 (Kidd et al., 1998) and 1999 (Kearns et al., 2002). Information on all aspects of pesticide usage was collected from holdings throughout the province. Quantitative data have been adjusted to provide estimates of total pesticide usage. The area of vegetable crops grown in Northern Ireland in 2004 was 1639 hectares; a 6% increase compared with 1999. By comparison with 1999, the pesticide-treated area increased by 8%, to 11,299 spray hectares, while the weight of pesticide (active ingredients) remained similar to 1999 at approximately 7 tonnes, indicating an increase in the number of spray applications but a decrease in the weight of pesticide applied per treatment. The fungicide-treated area increased by 21%, while the weight of fungicide active ingredients (a.i.) applied decreased by 20%. Overall, both the application area and weight of herbicides and desiccants applied increased by 23% and 16%, respectively. Both the treated area and the weight of insecticides applied decreased by 13% and 49%, respectively. The area treated with molluscicides and the weight applied decreased by 60% and 79%, respectively. However, 1999 recorded a significant rise in molluscicides compared with previous years and the 2004 applications are more comparable to usage pre-1999. The area of vegetable crops sown or planted with treated seed increased by 37% in the five-year period 1999 to 2004 and the weight of active ingredients used also significantly increased. Fungicides, applied to 22% of the pesticide-treated area, accounted for 14% of the weight of pesticides applied. Herbicides and desiccants accounted for 41% of the pesticide-treated area and 77% of the total weight of pesticides used. Insecticides, applied to 29% of the pesticide-treated area, accounted for 8% of the total weight of pesticides used. Seed treatments applied to vegetable crops grown in 2004 accounted for 7% of the pesticide-treated area representing less than 1% of the weight of active ingredients applied. Molluscicides accounted for 10% of the total pesticide-treated area and less than 1% of the weight of pesticides applied to vegetable crops grown in Northern Ireland in 2004. Brassica crops received 30% of the total weight of fungicides applied, representing 39% of the area of vegetable crops treated with fungicides. The single most commonly used fungicide active ingredient applied to brassicas was difenoconazole. Carrots and parsnips collectively accounted for 42% of the weight of fungicide active ingredients applied, representing 43% of the area treated with fungicides, with the active ingredient azoxystrobin being most frequently used on these vegetable crops.

Trifluralin was the herbicide/desiccant active ingredient most commonly applied to vegetable crops, particularly brassicas. Overall, 25% of all herbicide/desiccant applications were applied to brassica crops. Carrots and parsnips collectively accounted for 52% of the insecticide-treated area, representing 17% of the weight of insecticide active ingredients applied. Brassicas accounted for 41% and 74% of the insecticide-treated area and weight applied, respectively. Pyrethroids were the most frequently used insecticide active ingredients, particularly lambda-cyhalothrin, which was the most frequently used insecticide.

For further information on this work please contact: Pesticide usage monitoring group