Å UMARSKI LIST 1-2/1973

The contentration of potassium under which it is possible to expect a positiveaction of potassium fertilizers on the growth of Scots Pine was established byHeindsdorf with 0.5°/o K. Concentrations of potassium in all our cultures are higherthan this value, and therefore from the fertilization with potassium no more significanteffects can be expected.By excepting maybe culture 6 at Vidina Loza as regards nutrition with phosphorus,the state of nutrition with other investigated nutrients in all cultures maybe estimated as favourable.As visible from what has been stated, the estimate of our results was given onthe basis of investigations in Germany, which estimates ought also to be taken witha grain of salt. A safer estimate on the need to fertilize cultures of Scots Pine in theregion of Karlovac may be given only on the basis of results of fertilizing experimentsunder similar ecological conditions.3S