Stand development during 16–57 years in partially harvested sub-alpine uneven-aged Norway spruce stands reconstructed from increment cores

• Long term effects of partial harvests were reconstructed from increment cores.
• A structural definition termed ‘full-storied’ is suggested.
• Average ingrowth was 13.3 stems ha−1 yr−1, and not related to standing volume.
• All seven stands developed inversely J-shaped diameter distributions.
• Volume increment increased with standing volume in all stands but one.

Long term effects of partial harvests were studied in seven uneven-aged Picea abies (L.) Karst stands in northern Sweden, by reconstructing stand development from increment cores. All stands had been subjected to partial harvests 16–57 years before the inventory. Two 1000 m2 circular plots were established in each stand. All trees with a diameter at breast height (1.3 m above ground) ⩾5 cm were mapped and calipered. Historic stand development was reconstructed backwards in five year intervals to the year of the previous harvest, using increment cores taken from randomly chosen sample trees in each 2-cm diameter class.The pre-harvest stem density was restored in all stands but one, at the time of the inventory. Average ingrowth of survived trees was 13 stems ha−1 yr−1, but no relation was found between annual ingrowth and standing volume. Only four stands had inversely J-shaped diameter distributions after harvest, but all seven stands did at the time of the final inventory. Standing volume was 34–88 m3 ha−1 after harvest and 126–207 m3 ha−1 at the final inventory, with an average volume increment around 3 m3 ha−1 yr−1 for the whole observation period. Volume increment increased with standing volume in all stands but one. The shapes of the diameter–height curves were similar for all stands, irrespective of the time elapsed since the harvest. In conclusion, the results from this study indicate that the selection system is a sustainable silvicultural system in uneven-aged sub-alpine Norway spruce forests. These forests have high resilience and a capacity to recreate stable diameter distributions after rather harsh treatments.