Variable rate application of lime on paddocks

Variable rate application of lime on paddocks

Lime is the most widely used fertiliser/soil conditioner product in New Zealand. Its application ensures crop growth and there is a strong correlation between crop yields and evenness of application.

Lime is a very challenging material to spread due to its fine particle size and its non-uniform size. It is not very mobile in soil and its adhesive properties means it easily cakes into lumps rather producing a smooth powder with continuous granular flow.

Working with Ravensdown and the Foundation of Arable Research (FAR), an industry levies funded organisation, Lincoln Agritech assessed techniques on how to optimise lime spreading paddocks relevant to variable rate applications. The spread quality was assessed by driving the trucks, loaded with lime, at different speeds. Five different trucks were tested over application rates from 500 to 5000 kg/ha at different driving speeds. The main aim was to get a wide dressing of lime so paddocks are sufficiently top-dressed with minimum number of truck passes.

This project was funded by Ravensdown and FAR, and the measurements were conducted with support from Russell Horrell.

Image: Lincoln Agritech researchers, Scott Post and Peter Carey, doing field work. Photo taken by Ravensdown.