Underplanted silver fir and common beech cause changes in root stratification and morphology in mature spruce stands

: In this study we analysed changes in dis tribution and morphological properties of fine roots caused by underplanting of a 110-year-old Norway spruce monoculture by silver fir and common beech. Three different stand structures were investigated: mature established each quantified ic were calculated. Root-to-root interaction of spruce and underplanted species led to differences in verti cal distribution of roots towards the more homoge nous root density in investigated profile with clear shifting of beech and fir roots into deeper soil lay -ers. Cumulative root fractions of fir and beech in up per 20 cm were lower than those of Norway spruce. The share of spruce roots in depth under 20 cm never exceeded 20%. The co-occurrence of beech and spruce in small spots was about twice as fre quent as the co-occurrence of spruce with fir. We found differences in SRL and SSA between broad leaves (beech) and conifers, while the values of beech morphological parameters increased signifi -cantly, when mixed with spruce. We assume that the competitive strategy of beech is based in changing its root morphology, whereas silver fir is inclined to extend its biomass.