Scots pine growing on forested mires in Abernethy Forest, Strathspey, Scotland

Abstract

A substantial proportion of the Abernethy Forest Reserve has Scots pine (Pinus sylvestris) growing on the surfaces of a variety of mires. The hydrology of the mires has been affected by drainage and peat cutting but this area is unusual in having had a long period of protection from grazing by domestic stock. There are three main types of pine populations found on these mires. Woodland bog comprises predominantly bog vegetation with abundant pine seedlings due to the heavy seed rain from the surrounding woodland. Only a few very small trees survive, which are stunted, heavily diseased and have very low seed production. Wooded bog also comprises predominately bog vegetation but there are scattered mature trees of a moderate height with an open canopy. The trees are fertile and can form uneven aged stands with regeneration. Bog woodland is a predominantly woodland vegetation with tall, dense tree cover on deep peat. The trees are well grown with a dense canopy. A few remnants of bog vegetation remain in the ground flora although most have been replaced by woodland bryophytes and shrubs. Each of these three types is described and their development is discussed.

Ecological survey of the native pinewoods of Scotland 1971

“…Information from surveys pertaining to the Scottish pinewoods predating this one tends to have been collected in a unrepeatable fashion or has not been as fully comprehensive in terms of the range of data collected (Smith, 1900;McVean and Ratcliffe, 1962;Steven and Carlisle, 1959). Subsequent surveys relating to the pinewoods have been on a smaller, localised scale, focused on specific sites (Mchaffie et al, 2002;Wilson and Puri, 2001;Vickers and Palmer, 2000) and are often focused on one particular aspect of the ecosystem, such as a particular species (often not restricted to the pinewood habitat) (Wilkinson et al, 2002;Summers and Buckland, 2011), forest structure (Mason et al, 2007;Summers et al, 1997) or regeneration (Scott et al, 2000;Baines et al, 1994;Palmer and Truscott, 2003). Some studies solely focus on areal extent (Roberts et al, 1992;Cameron et al, 2000).…”

Vegetation and ombrotrophy on the mires of Abernethy Forest, Scotland

“…Table shows total number of quadrats with water samples in each vegetation type, the number associated with telluric influence, the proportion with telluric influence (with significant positive associations in bold, significant negative associations in italic) and the χ 2 test of contingency. (McHaffie et al 2002), mostly below 4 m tall but exceptionally 10-12 m (and in other parts of Abernethy aged up to 200 years or exceptionally 335 years old, Anderson and Harding 2002). This suggests that these wooded bogs can be more-or-less in a steady state with germination and early establishment limited by competitors, but later stages of growth limited by high water tables, though the tree dynamics may be very susceptible to disturbance of the water table or ground vegetation, and to browsing.…”

“…Most of the sites considered in this paper lie within the Cairngorms Special Area of Conservation (SAC); Bog woodland (91D0) is a priority habitat under Article 17 of the EC Habitats Directive (www.jncc.gov.uk/ SACselection; Wells 2001). The present work was part of a major cooperative project to evaluate the nature conservation potential and possible management needs of the mires (in part with only sparse tree cover) within the forest (McHaffie et al 2002;Scottish Natural Heritage 2002;Caledonian Partnership 2003;Legg et al 2003). Our broader objective was to understand the distribution and dynamics of the gradient from open mire through sparse tree cover to densely wooded bogs.…”

Adding time to the conservation toolkit: palaeoecology and long term wetland function dynamics

“…For example, woodlands are found to have repeatedly expanded onto peat surfaces during earlier stages of mire development (Chambers 1996;Whitehouse in review). In some cases, these woodlands developed from fen woodland occupying the site before the switch to mire 1 C development occurred, but distinctive wooded bog and bog woodland communities also occur, often dominated by pine (MacKenzie and Worrell 1995;McHaYe et al 2003). Many bog woodlands persisted over millennia, contracting during wetter periods and re-expanding during periods of surface dryness (Boswijk and Whitehouse 2002).…”

“…Many bog woodlands persisted over millennia, contracting during wetter periods and re-expanding during periods of surface dryness (Boswijk and Whitehouse 2002). Taking a palaeoecological perspective it is quite clear that these bog woodlands are part of the raised mire ecosystem and that they play an important biodiversity role on sites (Chambers 1996;McHaYe et al 2003). Yet today, trees colonising the mire surface are generally treated as undesirable invaders.…”