Mapping the risk of damage from tree roots for the conservation of archaeological sites: the case of the Domus Aurea, Rome

Abstract

Damage caused by tree root growth to archaeological monuments buried underground, over the course of centuries, has been frequently reported in the city of Rome. The Domus Aurea, Nero's Imperial residence, now lies under the Horti Traianei (Trajan's Park) on the Oppian hill. These gardens, planted at the beginning of the last century, are located only 3–4m above the surviving archaeological structures. In some cases roots have damaged the underlying vaults, sometimes creating serious structural problems. Results of the study show that a variety of species with strong root systems growing for many metres laterally, and to depths of several metres, are present. Identification of the plants responsible for the damage has been achieved through a study of the anatomy of their wood. A real and potential assessment of the risk posed by tree roots to the archaeological structures has been attempted. The data collected will contribute to evaluating the risk to monuments under similar conditions and will also help to avoid errors made in managing the plant cover of archaeological sites