GROWTH ANALYSIS OF SCOTS PINE AND LODGEPOLE PINE-SEEDLINGS

Possible reasons for the superior growth rate of lodgepole pine (LP) ( Pinus contorta Dougl. var. latifolia Engelm.) compared to Scots pine ( SP) (Pinus sylvestris L.) were investigated in a trial where the speci es were grown in large pots with sand, till or topsoil, during 4 years following sowing. Although starting with lower seed mass, LP seedling s had greater mass than those of SP at the end of the study period. Th ere was, however, a species x growing media interaction and the differ ence in final mass was greatest for seedlings growing in topsoil. Grow th analyses showed that the faster relative growth rate in LP seedling s was linked with a higher leaf area ratio, specific leaf area and nit rogen use efficiency. A higher relative allocation to thin roots was a nother trait of LP that may contribute to its superior productivity. T he fast root growth suggests shorter cultivating time of potted LP see dlings to avoid root deformation. SP allocated relatively more to stem and thick roots, components associated with physical stability. There was no species difference in allocation to needles when relating to t otal biomass, but LP had a larger proportion of needles in relation to above-ground biomass.