Growth response of advanced planted European beech (Fagus sylvatica L.) after storm-caused loss of shelterwood

Outcomes after an abrupt, storm-caused loss of spruce shelterwood (Picea abies L. Karst.) overstories on advanced planted beech (Fagus sylvatica L.) were investigated, including effects of developmental stage and beech stand density on growth after release. Six years after overstorey loss by storm Kyrill in January 2007, heights and root collar diameters were measured, along with annual length of the main shoot and ring widths of the stem and strongest branch. No significant difference in the total height of released and sheltered beeches was found at six years after shelter loss, but annual growth of the main shoot of released beeches increased from the second year after release. Overall growth patterns of released and sheltered beech differed significantly. Diameter growth and that of the strongest branch increased strongly after shelter loss. Height-to-diameter ratio (H/RCD) indicated that sheltered beeches with higher densities were slenderer. However, no differences were found in growth response between young stands and beech in the thicket live stage. Overall, advanced planted beech beneath a spruce shelterwood of medium canopy closure showed vigorous height growth and a qualitatively desired form. Sudden release of the planted beech enhanced diameter growth of stem and branches, which is undesirable for timber quality. Findings suggest that advanced planted beech should not be released by abruptly cutting the shelterwood. Instead, with stepwise canopy opening beech should gradually adapt to the open conditions.