Clark DEB-9806877 The true bamboos are a diverse group of grasses with worldwide distribution, including at least 1,200 species of both woody and herbaceous (non-woody) members. The bulk of bamboo diversity is found among the woody bamboos, which includes 1,100 species occurring as characteristic elements of both tropical and temperate forests. Due to their structural complexity and long intervals of growth without flowering (40, 60, or 80 or more years in some cases), the woody bamboos remain understudied compared to other grasses. Molecular data have provided some clues to evolutionary relationships among woody bamboos, but an apparently slower rate of mutation relative to other grasses has prevented more detailed analyses of this group. Available data for anatomy and whole plant structure of bamboos provide indications of ancestry among woody bamboos that conflict with those derived from molecular data. The principal objective of this research is to examine this conflict in the determinate, one-flowered woody bamboos by conducting detailed structural analyses to obtain a better estimate of evolutionary relationships. As part of this research, a taxonomic study of the most primitive members of Chusquea, the most diverse genus of this subset of woody bamboos, will be completed. The results of this project will provide the foundation for a broader evolutionary study and reclassification of the woody bamboos.