Pesticide usage report: Grassland & fodder crops 2009

Summary

This is the sixth survey examining pesticide usage practices on grassland and fodder crops in Northern Ireland, providing data comparative to that obtained from previous surveys in 1989 (Jess et al., 1992), 1993 (Jess et al., 1995), 1997 (Jess et al., 2000), 2003 (Withers et al., 2005) and 2005 (Withers et al., 2007). In this survey, information on all aspects of pesticide usage was collected from 324 enclosed grazing, 36 arable silage, 33 fodder maize and 20 other fodder crop holdings throughout the Province, representing 2.9% of the total area of grassland and fodder crops grown. Quantitative data obtained were adjusted to provide estimates of total pesticide usage.

Overall, the area of grassland and fodder crops grown in 2009, 1,145,386 ha,  increased by 2% when compared to 2005. The area of established grassland crops also increased by 3% throughout this period. The area of fodder crops grown in Northern Ireland in 2009 increased by 45% compared to that recorded in 2005. This was principally due to the increase in fodder maize production. A fourth cut of silage was recorded for the first time in 2005 and this recurred in 2009.

The area of grassland and fodder crops receiving pesticide treatment, decreased by 21% when compared to that recorded in 2005. Both the pesticide-treated area and the weight of pesticides applied were the lowest recorded in any survey. A total of 75 tonnes of pesticides was applied to 101,998 spray hectares of grassland and fodder crops during 2009. This represented a 12% reduction in the weight of pesticides applied compared to 2005. Herbicides accounted for 78% of the pesticide-treated area, representing 96% of the weight of pesticides applied. Seed treatments accounted for a further 12% of the treated area. The weight of active ingredients applied as seed treatments represented less than 1% of the total active ingredients. Fungicides, insecticides and growth regulators collectively accounted for the remainder of the total pesticide usage. No molluscicide use was recorded during this survey.

The areas of enclosed grazing and grass silage treated with pesticides decreased by 38% when compared to the 2005 survey, returning to a level similar to that recorded in 1989. Correspondingly, the weight of pesticide applied to enclosed grazing and grass silage decreased by 38%. Pesticide usage on sown grassland crops increased by 25% when compared with 2005 and the weight applied increased two-fold. This was due mainly to increased applications of herbicides to grass reseeds. The increase in the area of fodder crops when compared to 2005 was mainly attributed to a 43% increase in the area of fodder maize. The pesticide-treated area of the maize crop increased by more than two-fold from 5,993 spray hectares (spha) to 13,751 spha. However, the weight of pesticides applied increased by only 10%. This was due to the withdrawal of atrazine and the application of the formulations bromoxynil/terbuthylazine and flutenacet/isoxaflutole. The formulation mesotrione/terbuthylazine was also frequently applied.

Herbicides remained the most extensively used pesticide type on grassland and fodder crops. The use of herbicides decreased by 21% between 2003 and 2005. This continued between 2005 and 2009 showing a 32% reduction. The trend for reduced weight of herbicide applied since 1989 also continued. The formulation of fluroxypyr/triclopyr was the most frequently-used herbicide, principally applied to the first-cut of grass silage to control docks (Rumex spp.).

A total of 112 products comprising 70 active ingredients were recorded in use in this survey.

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