Abstract

Following boreal forest ecosystem disturbance, such as fire and clear-cutting, the ericaceous species Calluna vulgaris often becomes completely dominant and may convert forestland into heathland. Calluna is known to effectively exclude other vegetation and causes ``growth check'' or stagnation of conifer seedlings to result in poor tree regeneration. In this study we investigated the use of steam treatment as an alternative method for vegetation control of Calluna vulgaris. Scots pine (Pinus sylvestris L.) establishment and growth were recorded in both a planting and a seeding experiment. Steam treatment was compared with mechanical soil scarification and intact vegetation in the planting experiment and with intact vegetation in the seeding experiment. The results show that the vegetation is still strongly reduced five years after the treatment. The steam treatment strongly favoured the establishment and growth of both seeded and planted Scots pine. The planted seedlings grown in the steam treated plots had a dry weight more than twice as high when compared to scarified plots. Seedling height and basal diameter were also highest for seedlings grown in steamed plots. Seedlings planted in scarified plots did not grow as well during the first years possibly due to injuries caused by frost heaving. The seeding experiment showed an increased establishment and growth of Scots pine seedlings in steam treated plots compared to in intact vegetation.

Keywords

competition; forest regeneration; ground vegetation; site preparation; soil scarification; vegetation management

Published in

New Forests
2001, volume: 21, number: 2, pages: 187-198
Publisher: KLUWER ACADEMIC PUBL

Authors' information