Liming agricultural soils in Tasmania, Australia, from 1940 to 2020: acidity of the soils and the sources, production, quality control, transport and current patterns of lime use

Production and sources of agricultural limestone and dolomite in Tasmania are considered in the context of their geology, the acidity of their surface soils, transport and current patterns of use. The Tasmanian Government paid a rail freight subsidy between 1940 and 1980 to encourage on-farm use of ground lime products. Regulations and registration were adopted in 1955 to ensure minimum standards for neutralising value and particle size. Registration ceased in 2005 when the regulations were changed to align with other Australian states.
The production of ground agricultural liming materials increased from 4 kt in 1940 to 75 kt at the time the transport subsidy ceased in 1980. Subsequently, annual production continued to gradually increase to a peak of 207 kt in 2001, but then declined to an average of 145 kt between 2006 and 2020. Current lime use is substantially in excess of the amount required to neutralise the acidifying effects of nitrogen fertilisers. The evolution in the methods of quarrying, transport, costs and quality control between 1940 and 2020 are reviewed.