A survey of the nutritional status of north Queensland sugarcane soils with particular reference to zinc

More than 15% (18 000 ha) of north Queensland sugarcane soils from Mossman to Ingham were estimated to have less than the critical value of 0.6 mg Zn/kg soil by 0.1 M hydrochloric acid extract. Extractable zinc in soils followed the order: metamorphic, beach ridge and granite soils < organic and alluvial soils < basaltic soils. Locations of low zinc soils were mapped. Calcium and/or magnesium were deficient for 34% of soil samples and sulfur was deficient for four percent of samples. Reduced phosphorus and potassium applications where soil levels are adequate would help pay for application of other deficient nutrients.