Effects of shelterwood method and plant stock type on the early growth and survival of pine seedlings in regeneration stands under hemiboreal conditions

Shelterwood forest regeneration methods are increasingly used in northern Europe to reduce clear-cut based even-aged forest management. However, empirical knowledge about seedling performance under various shelterwood methods is still incomplete. We analysed the effects of three shelterwood methods (uniform (UNI), strip felling (STR) and group selection (GRO)) on four types of Scots pine plant stock type height growth and survival during the first 6 years in hemiboreal Estonia. After 6 years, the height of the planted seedlings was 35% lower in GRO and 47% lower in UNI compared to STR. A similar outcome was observed for the height growth of the sown seedlings. Competition with the nearest shelter trees had a negative effect on seedling height growth. Lower height growth in UNI can be attributed to more intensive root competition with shelter trees. Artificial sowing and natural seeding can provide sufficient regeneration, but height growth was significantly lower compared to that of planted seedlings. Shelterwood methods delay seedling growth compared to clear-cut area reforestation. The lag in regeneration height growth was the smallest in STR and the greatest in UNI. The growth lag can be reduced by using complementary planting to natural regeneration.