This 2008 report summarizes an inventory of tamarisk and Russian olive infestations on all the major rivers and their main tributaries in Colorado. The report was completed by the Tamarisk Coalition for the Colorado Water Conservation Board. The purpose of this work was to 1) establish and implement an inventory protocol that would be economical to perform, 2) provide a relatively accurate understanding of the extent of the tamarisk problem in Colorado, 3) develop water and wildlife habitat impacts, and 4) estimate the cost of restoration.