30 June 1995

Mapping use of inputs

INPUT adjustment without a yield map is possible, claims Anna Budden of SOYL. Nutrient maps can be used to adjust fertiliser inputs using a variable rate applicator, so cutting costs, she says.

Ms Budden counters criticism that one sample a hectare is not sufficiently accurate, stressing that the method has to be economic.

The SOYL system is now more precise thanks to gradual rate changes, rather than sharp cut-offs between application levels. It can also superimpose moisture holding capacity and soil type to improve the picture of nutrient availability.