Trace elements (such as chromium, copper and boron) often perform essential functions in plants and animals. Small quantities can be found in the soil. Shortages often have an adverse effect on quality, yield or the health of livestock or humans. In plants, shortages cause deficiency symptoms such as heart rot in sugar beet.
Sandy soils are more likely to be deficient because trace elements can leach out of them more easily. Too much phosphate can also be detrimental: it can, for example, reduce copper and zinc absorption. The pH also plays a key part in maintaining the availability of trace elements. If the pH is too high or too low, fewer trace elements will be available to the crop.
Laboratories can provide analyses for various trace elements. Because the quantities involved are very small, it is essential to determine very precisely the diagnosis and any application rate.
Note that it is not possible to deduce from the total sulphur or nitrogen content whether these nutrients are also available. The sulphur or nitrogen has to be released by the soil life.
Rottink, A., A. Termorshuizen, A. Reijneveld, P. van Vliet, I. Ketelaar en M. Hermans (2007). De bodem doorgrond. BLGG Oosterbeek. ISBN 978-90-812265-1-6. 96 p.