The first imported roofing material was corrugated iron sheeting. Roofs of this type were to become part of the Australian vernacular. For many years imported roofing was in very short supply. Two local roofing materials were available- there were extensive reed beds near the Cook's river for thatching. There was also bark which could be peeled off a number of the indigenous trees in large sheets. Methods of heating and flattening the bark were used by the Aboriginal people and these were quickly assimilated by the convict builders.