Effects of whole-tree harvesting on growth of pine and spruce seedlings in southern Finland

The effects of harvesting logging residue on the survival and growth of planted Scots pine (Pinus sylvestris L.) and Norway spruce (Picea abies (L.) Karst) seedlings and on number and growth of natural seedlings were studied at five sites in southern Finland. Trees were harvested either conventionally, i.e. harvesting only the stems, or harvesting all the aboveground tree biomass (WTH). One of the experiments had been planted with pine and four experiments with spruce 10 years ago. When the spruce experiments were analysed together, WTH had significantly increased the average number of planted seedlings, but had not affected basal area, stem volume or biomass of the planted seedlings. When both planted and natural seedlings were studied together, WTH significantly increased the average number of seedlings and the average total biomass of all tree species. In the pine experiment, WTH had no effect on stand or tree characteristics. In this study, within the first 10 years after reforestation, WTH did not have any negative effect in stand or tree characteristics that could be explained by nutrients removed with logging residue.