Implications of retaining woodland cover for managing archaeological evidence in wooded environments

There are too many archaeological sites in the UK to manage them all as open grassland. Tree cover on, or surrounding, suitable sites may offer a form of long term, low cost, physical protection. Forests have arguably prevented the destruction of some archaeological evidence compared with other agencies such as intensive agriculture or commercial development. Additionally, many archaeological features such as saw pits of charcoal platforms, are directly associated with the woodland’s history and its past management. Thus, tree removal may be inappropriate.

Potential issues relating to tree retention

There are many potential ways in which tree cover can influence archaeological evidence but the likelihood of any impacts are also dependent of a range of site-specific variables. With many of these issues, management options can be implemented to reduce any risks and develop a suitable mitigation strategy. This requires sensitive management with an informed understanding of the potential risks, the available options and their consequences. However, for the majority of these potential issues, there is a need for a greater understanding.

Some examples of potential issues where trees are retained include:

• Forest operations
• Tree root growth
• Changes to a soil’s chemistry and hydrology
• Risk of windthrow

Published studies into woodland impacts

Archaeological literature reports well preserved remains under woodland but they usually refer to monument form, and impacts below ground have often not been investigated. Such investigations in woodlands are few, as physical surveying and excavation is more problematic. Two studies in Scotland have been commissioned to specifically assess the impacts of the cultivation used prior to afforestation and subsequent tree rooting. At both sites, the archaeological evidence occurred within the rooting zone, but the reports concluded that the majority of damage was caused by cultivation, and that root induced problems were local and did not prevent archaeological interpretation. However, the reports identified the need for further research on a wider range of soil types, tree species and archaeological evidence.