Woodland vegetation and its implications for archaeological survey using LiDAR

Abstract

Archaeological surveys in woodland have always been problematic and many woodlands contain an unrecorded archaeological resource. For other types of rural landscape, aerial photographs are often used to map archaeological features but woodland cover has always impeded such disclosure. Remote sensing methods are rapidly evolving and are used both within forestry and archaeological disciplines for a range of applications. This paper considers the exciting application of the remote sensing technique of airborne Light Detection and Ranging (LiDAR) to reveal archaeological evidence previously hidden below a woodland canopy. Our research shows how different types of woodland canopy and understorey vegetation greatly influence the effectiveness of the LiDAR to perform these surveys. A simple, visual vegetation mapping assessment is tested and its ability to predict the potential of the LiDAR considered. This work highlights the importance of vegetation awareness when considering both a new LiDAR survey for a woodland, and when interpreting the data. Simple estimates of LiDAR penetration of the woodland canopy and understorey vegetation can be used to predict the effectiveness of a LiDAR survey in disclosing archaeological evidence and aid the interpretation of results. © Crown Copyright 2007.