Maintaining soil fertility in extensive grazing pastures is an important factor in ensuring that pastures reach their potential in terms of yield and quality. It is currently perceived that many soils under extensive grazing pastures are either deficient in critical nutrients or have nutrient levels above optimum for pasture production. The potential of soil acidification in improved extensive grazing pastures with legume components is also an issue. Furthermore, it is thought that many graziers fail to conduct soil tests prior to applying fertiliser. Observations pertaining to excessively high soil nutrient values are supported by research from the dairy industry, where levels of P, K and S are often above the optimum levels for pasture growth (Burkitt and Coad 2006; Gourley et al. 2010). Nutrient levels have been studied less intensively in pastures used for extensive sheep and beef grazing.
Funding
The Northern Tasmanian Natural Resource Management Assoc Inc.