Postfire succession in juniper and pinyon-juniper is primarily dependent upon the potential of the site, the preburn plant community and the characteristics of the fire. The successful use of prescribed burning is dependent upon the appropriate selection of treatment sites. As juniper and pinyon become more dominant on a site, the shrub and herbaceous layers decline in productivity. This reduces the fine fuels on the site making it more difficult to burn. There are also fewer herbaceous perennial plants remaining in the sites with greater tree dominance and the response of this component is less than that of sites burned at an earlier stage of juniper invasion. Treatment sites should be selected that are in stages of succession that can be efficiently burned in an economical and environmentally sound manner.