Sulphur: crucial role working alongside N

摘要

It is a curious paradox that the area of grass receiving sulphur fertilisers in Britain is falling whilst agronomists are virtually united in their views that this vital nutrient should be more widely used. According to a recent survey only 5 percentof the crop area of silage grass received sulphur fertiliser in 2001, the lowest level since 1993 and only half of the area treated in the year 2000. Even where silage ground is treated, the application may not be adequate as the survey suggests that 15-20kg S/ha has been applied and, if grass needs 15kg per cut, then places where two or more silage cuts are taken may not be achieving optimum yields. This is surprising as the sulphur "story" is now well known. From the 1850s onwards crops received their sulphur requirements in the form of atmospheric deposition from industrial pollution but this began to decline rapidly in the 1970s owing to controls on sulphur emissions.