Response of a Scots pine (Pinus sylvestris) stand to application of phosphorus, potassium, magnesium and lime: 3. Foliar nutrient concentrations and stand development.

In 1985-88, a 25-yr-old Scots pine forest in Netherlands was limed and fertilized with P, K and Mg in a factoral design. This paper addresses effects of these treatments on foliar nutrient concentrations and tree growth. Stem volume increments of individual trees were measured. Average annual volume growth was estimated to be about 16 msuperscript 3/ha, which may be a slight underestimation. P and K showed increased foliar concentrations immediately after treatment and were the only elements that significantly increased volume growth in 1988-91. Additional annual volume growth of individual trees brought about by P and K corresponded with 0.9 and 2.2 msuperscript 3/ha, respectively. Foliar Mg and Ca increased later and insignificantly reduced and increased volume growth, respectively. Lime and Mg applications tended to lower foliar N. When absolute foliar concentrations and element ratios were compared to Dutch and German standards, it appeared that application of some of these standards in present research would not always have given a fully correct prediction of growth responses to nutrient additions