We examine the Indigenous uses, oral histories, and knowledge of native Guadua bamboo species in southwestern Amazonia. Two Guadua species form dense stands in which individual plants die en masse at regular intervals of about 28 years. Scholars suggested that pre-colonial earth builders took advantage of these die-off events as a natural aid in removing the forest to construct geometric earthworks. Our results show that Guadua species have a significant position in Indigenous socio-cosmologies, land use, and as a protector of diverse resources. Indigenous ontological understandings cannot be separated from discussions of the abundance and geographical distribution of Guadua as a critical controlling factor in the vegetation structure and function of southwestern Amazonian rain forests. Furthermore, oral histories point to the connection between land management and bamboo, as well as bamboo and the use of fire, conforming to the suggestion of opening ceremonial spaces in bamboo patches in pre-colonial earthwork societies.