The ecological history of the forest of Abernethy, Inverness-shire

Abstract

Pollen-analytical, stratigraphic and historical investigations into the ecological history of the Forest of Abernethy, Inverness-shire, reveal that pine-dominated forest has persisted in the area since early Middle Flandarian time. (c.7-8000 BP). Comparisons between fossil pollen assemblages and pollen spectra contained in modern terrestrial and lake-mud surface samples and lake-mud surface samples suggest that the Mid-Flandarian forest in the area contained a greater admixture of Birch than is at present. It may, therefore, have been a mixed forest of Pine, birch and other deciduous, pioneer tree species.

Pollen analysis and radiocarbon-dating of material contained in the organic layers of podsols in Abernethy suggests that the initial recognizable expansion of heartland within the forest occurred from c. AD 400 onwards, the period of Pictish Dark-age and Medieval settlement. By the mid-C18th, the afforested area in Abernethy had been reduced to its approximate present extent.

During the C18th, an expansion of agriculture and commercial forestry resulted in the clearance of much of the remaining forest, which was either replanted, or allowed to regenerate in the mid-C19th. Since then, further forestry and grazing by deer have discouraged regeneration, which is confined to a few areas only.

Various theories concerning the degradation and failure of regeneration of the Scots pine communities in the Highlands are discussed in the light of the evidence from Abernety. The degradation and regeneration failure in the forest is thought to be largely the result of the long span of small-scale land-use from the Dark Ages onwards rather thana late, C18th expansion of human activity. While the mixed pine and birch dominated forest persisted, regeneration occurred periodically, and podsclization under heath, or solely Pine-dominated forest, did not take place, due to the “soil-improving” properties of the litter of Birch, Rowan and Juniper, and herbaceous field-layer plants.

The effect on the forest of subsequent land-use has been to modify its composition inn favour of Pine and Dwarf-Shrubs. The factors seen as crucial are forestry, which eliminates pioneer deciduous trees, light-grazing, which limits regeneration and aids the spread of Calluna vulgaris, and repeated burning, which maintains large areas of former forest as Heather Moor.

Date of Award	1970
Original language	English