Management of Louisiana’s historic bousillage buildings

In the south eastern United States of America and particularly in Louisiana, a distinct form of colombage construction - Bousillage - is found. This earth construction method uses `loaves' or `cats' of earth applied over cedar wood battens. A highly distinctive characteristic of the method is the incorporation into the earth mixture of an indigenous epiphyte plant called Spanish Moss (Tillandsia usneoides) following the harvesting and alengthy pre-treatment of this plant fibre. Today, over 140 years since these heritage buildings were constructed, these bousillage structures are subject to repeated repair. Arange of repair management practices is found reflecting both the broad range of ownership and the range of heritage protection designations applied to these buildings. Focusing upon the contrast between repair materials and historical materials micromorphology analysis and near-infra red spectroscopy this study reveals clear differences in the organic components found in modern repair materials. Whilst the repair methods presently used on bousillage follow historical and ethnographically recorded practices, there are significant differences in the use of Spanish Moss. This raises concerns that there may be changes in the performance of the building structure in the long-term.