Establishment and development of northern white-cedar following strip clearcutting
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- 作者：Heitzman ; Eric ; et. al.
- 关键词：Northern white-cedar ; Strip clearcutting ; White-tailed deer ; Stem analysis ; Regeneration
- 刊名：Forest Ecology and Management
- 出版年：1999
- 出版时间：November 8, 1999
- 年：1999
- 卷：123
- 期：2-3
- 页码：97-104
- 全文大小：172 K
文摘
Overbrowsing by white-tailed deer (Odocoileus virginianus) has created difficulties in regenerating northern white-cedar (Thuja occidentalis L.) in Michigan during the last 30 years. This has prompted concerns among resource managers regarding the long-term sustainability of cedar forests. After reviewing many areas, we identified three that were strip clearcut 20–30 years ago and had successfully regenerated. We determined patterns of species establishment and height growth and computed the time interval over which this cedar was vulnerable to browsing by deer. Cedar comprised 51–82 % of all trees and 36–70 % of overstory trees in the three study areas. Balsam fir (Abies balsamea (L.) Mill.), black spruce (Picea mariana (Mill.) B.S.P.), and white spruce (P. glauca (Moench) Voss) were important associates. Seedling establishment in these stands had continued for up to 20 years after clearcutting. However, all overstory trees were derived from advance regeneration or from seedlings that established within the first 10 years after cutting. Seedlings that established early but were overtopped by faster growing trees, or seedlings that established later than 10 years after cutting, were restricted to understory positions. It took 23–26 years after logging for two of our study sites to become fully stocked with cedar that were tall enough to escape overbrowsing by deer. The third area had no trees of this size, even after 20 years. Cedar's successful regeneration on these strip clearcuts can be attributed to its aggressive colonization, the lack of faster-growing competitors, and limited herbivory over several decades. Extending this experience to other areas, where strip clearcutting has failed, will require an unprecedented, steadfast management policy.