baumzaehlen - Primeval Forests & Their Trees

©2017copyright christoph hase

Cape Breton Highlands National Park, Nova Scotia, Canada

 

This park (950 km2) consists of a high plateau at an elevation of 400-500 metres and bordering slopes, valleys and ocean shores. The forests can be called boreal rainforests. Annual precipitation is 1400–1800 mm but the climate is more continental than on the west coasts of North America and Europe. Forest fires are very rare, insect epidemics, fungal diseases and wind being the major disturbance agents.1

 

In the sheltered low elevation valleys, forests are mainly beautiful broadleaf forests. Nowadays, their dominant tree species are Opens internal link in current windowAcer saccharum (sugar maple) and Opens internal link in current windowBetula alleghaniensis (yellow birch). The latter is not particularly shade tolerant but maintains its co-dominant position by its rapid growth rate in canopy openings2. However, according to old studies, Opens internal link in current windowFagus grandifolia (American beech) has been the dominant before3. Now, F. grandifolia saplings may be plentiful in places, but Nectria (beech bark disease), a fungus native to Europe accidentally introduced to Nova Scotia in the early 1900s, kills F. grandifolia before it becomes a large tree. A 16 km2 area in the Grande Anse Valley has no logging history4; in the other valleys, there has been logging and even farmlands. The forests are not tall: in the Grande Anse Valley canopies reach 20-27 metres. Tree species diversity is relatively low and most species are easy to identify. Walking is easy.

 

In comparison with the above-mentioned valleys, the high plateau is like a different world: flat northern boreal forest and bog country. The dominant tree species are Opens internal link in current windowAbies balsamea (balsam fir) and Opens internal link in current windowPicea glauca (white spruce). They reach heights of 10-13 metres. The forest is very open and often boggy. True bogs and fens are also common, often with Opens internal link in current windowPicea mariana (black spruce) and Opens internal link in current windowLarix laricina (tamarack larch). On the upper valley slopes Opens internal link in current windowBetula papyrifera (paper birch) is common. The high plateau is very wild with no discernible human traces. Hiking there can be hard, due to the dense shrub layer; particularly shrub-like P. mariana on the bogs hinder progress.

 

A major problem in the park is moose over-population. Locally the moose was hunted to extinction by the beginning of the 1900s, but was re-introduced in the late 1940s. The wolf was also hunted to a local extinction, but is still missing from the ecosystem. Hunting is not allowed in the park area, so the moose population has grown continuously and was approx. 2000 in 2010. Consequently, forest regeneration is severely disturbed, and tree saplings are absent in many areas.

 

With the exception of certain strictly protected areas (like Grande Anse Valley), camping is allowed in the forests, but requires a permit from park wardens.

 

References:

 

1       Clayden, S. R., Cameron, R. P. & McCarthy, J. W. (2011): Perhumid Boreal and Hemiboreal Forests of Eastern Canada. In DellaSala, D. A. (ed.): Temperate and Boreal Rainforests of the World. Island Press.

2       Woods, K. D. & Whittaker, R. H. (1981): Canopy-Understory Interaction and the Internal Dynamics of Mature Hardwood and Hemlock-Hardwood Forests. In West, D. C., Shugart, H. H. & Botkin, D. B. (eds.): Forest Succession. Concepts and Application. Springer.

3       Mosseler, A., Lynds, J. A. & Major, J. E. (2003): Opens external link in new windowOld-Growth Forests of the Acadian Forest Region. Environmental Reviews, Vol. 11, Suppl. 1, pp. S47-S77.

4       Stewart, B. J. et al. (2003): Opens external link in new windowSelected Nova Scotia old-growth forests: Age, ecology, structure, scoring. The Forestry Chronicle, Vol. 79, No. 3

 

Official site:

 

http://www.pc.gc.ca/eng/pn-np/ns/cbreton/index.aspx


Acer saccharum (sugar maple) forest in Grande Anse Valley, elev. 80 m. Also Betula alleghaniensis (yellow birch), right, and small dead Abies balsamea (balsam fir), right centre.
Deer Lake, elev. 460 m. Abies balsamea (balsam fir) - Picea glauca (white spruce) forest.
Otter Lake at 430 m. Abies balsamea (balsam fir) - Picea glauca (white spruce) forest.
Moose in Otter Lake.
Acer rubrum (red maple) on steep slope in Grande Anse Valley. Note A. rubrum seedlings browsed by moose.
Acer pensylvanicum (striped maple) on steep slope in Grande Anse Valley; also Picea mariana (black spruce) foliage, left.
Acer spicatum (mountain maple) in Grande Anse Valley at 60 m; also Picea glauca (white spruce), center, and Betula alleghaniensis (yellow birch), right.
Young Fagus grandifolia (American beech) in Grande Anse Valley.
Older Fagus grandifolia (American beech) infested with Nectria. Grande Anse Valley at 50 m.
Quercus rubra (northern red oak) in Grande Anse Valley.
Betula alleghaniensis (yellow birch) - Acer saccharum (sugar maple) forest on foothills in Grande Anse Valley at 100 m.
Young Betula alleghaniensis (yellow birch) in Grande Anse Valley.
Mature Betula alleghaniensis (yellow birch) in Grande Anse Valley.
Grande Anse Valley, elev. 50 m. Old Betula alleghaniensis (yellow birch), right centre; B. alleghaniensis, extreme right with paler bark; Fagus grandifolia (American beech), background, next tree left from the big B. alleghaniensis; Acer saccharum (sugar maple), other trees.
Betula papyrifera (paper birch) at about 350 m. Also Picea glauca (white spruce), background.
Betula papyrifera (paper birch) grove at 400 m.
Woodland at 360 m. Betula alleghaniensis (yellow birch), big trees; Prunus pensylvanica (pin cherry), left centre; Abies balsamea (balsam fir), left. Tree regeneration browsed by moose, apart from Picea glauca (white spruce) saplings.
Abies balsamea (balsam fir) forest at 460 m.
Fen at 440 m. Larix laricina (tamarack larch); shrub-like Picea mariana (black spruce, left) and Alnus incana ssp. rugosa (speckled alder). Abies balsamea (balsam fir) - Picea glauca (white spruce) forest, background.
Larix laricina (tamarack larch) at 440 m. Also shrub-like Picea mariana (black spruce).
Picea mariana (black spruce) at 460 m.
Sorbus americana (American mountain-ash) on high plateau.
Some broadleaf tree species of Grande Anse Valley.