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Abstract. This project seeks to improve the evidence base and modelling capacity

underpinning recommendations for use of wet season spelling to recover poor condition

grazing land and design more reliable and cost-effective spelling options for producers across

northern Australia. There is limited experimental work or expert knowledge on spelling

strategies to improve or maintain land condition (McIvor 2011). Site 1 has a study on the key

combinations of timing, duration and frequency of spelling within a grazed ‘C’ land condition

paddock in Central Queensland for a five year period. Site 2 will be established in the 2nd

year of the project at the Wambiana grazing trial in northern Queensland on ‘C’ land

condition sites subject to moderate and heavy grazing. Data from field trials will be used to

improve the capacity of GRASP to simulate the impacts of different spelling and stocking rate

regimes on pasture conditions over a range of pasture community types and seasons. The

project will engage with producers and field staff at each site. Site 1 has had variable rainfall

over the previous decade with predominantly dry or very dry conditions. Good growing

conditions, prior to and during the first two summers of recordings have resulted in high

pasture yields and crown cover. Pasture yields have been high for both Bothriochloa

ewartiana and Aristida spp. While there has been a small improvement in land condition

overall, there has been minimal impact so far from the spelling strategies applied compared to

the continuously grazed control.