Heather moorland in the Scottish Highlands: the history of a cultural landscape, 1600–1880

The heather moorland of the Scottish Highlands represents a highly symbolic habitat for the region. Significantly, recent work by ecologists and palaeobotanists has stressed the strong anthropogenic role in its development. Indeed, so vital is the role played by human interference, heather moorland is now seen as a cultural landscape. Yet despite being seen as a cultural landscape, there has hitherto been no attempt to use available documentary evidence to understand how this human interference may have affected its development over recent centuries. This paper examines such evidence, paying particular attention to how human activity contributed to its expansion over the early modern period and to its decline from ca. 1800 onwards, exploring such themes as moor burning, the harvesting of young tree growth, and grazing levels and practices, both before and after the clearances. Particular attention is paid to how the spread of sheep after the clearances contributed to the decline of heather moor and the role that heavy sheep grazing may have played in the deterioration in the quality of Highlands pastures during the mid-nineteenth century.     

Considerations on the provenance determination of plant ash glasses using strontium isotopes

Strontium isotopic analysis has been proposed as a suitable method to determine the primary production location of ancient plant ash glasses. The technique is based upon the assumption that Sr enters this glass type with the plant ash used as a flux material, and that the ⁸⁷Sr/⁸⁶Sr ratio of the resulting glass reflects the geological provenance of that flux. In such case, the bulk Sr isotopic composition of the bedrock should be inherited unchanged in the plants growing on that bedrock. Different types of plant ash glasses have been shown to have widely differing ⁸⁷Sr/⁸⁶Sr compositions. In this study, the ⁸⁷Sr/⁸⁶Sr composition of several plant species growing on different bedrock types is measured, and compared to the bulk Sr isotopic composition and petrology of that bedrock. The paper shows that the ⁸⁷Sr/⁸⁶Sr ratio of these plants is a function not only, or even mostly, of the local geology, but also of the Sr isotopic composition of the total water consumed by that plant. This is highly likely to be both plant species dependent and dependent on the small-scale hydrology of the area immediately surrounding the plant. In this way, no definite relation between the isotopic composition of a geological outcrop and the plants growing on this bedrock can be inferred. Hence, the isotopic composition of a plant ash made from such plants is uncertain and moreover species dependent. Though groups of plant ash glasses can certainly be compared in time and space using Sr isotopes, it may prove difficult to ascertain a plant ash glass type to a specific geographical-geological region.