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water may be stored, as a result of a high density of dams, to mean the dif- ference between intermittent and perennial flow (Heede 1977, Jester and McKirdy 1966). Gullying may favor summer streamflow loss by encouraging rapid runoff, reducing bank storage capacity, and exposing shallow seeps and springs to evapotranspirative processes. Small dams in gullied streams could be especially effective in restoring summer streamflow through reversal of these conditions. While woody streamside vegetation undoubtedly transpires significant amounts of water, vegetation removal studies suggest that it is not always true riparian vegetation that uses the most water along smaller streams (Rowe 1963, Rich and Thompson 1974). In some cases, it has been removal of pseudoriparian vegetation (Campbell and Green 1968), such as conifer and chapparal, which has resulted in the greatest increases in streamflow. Understory release studies in Oregon (Winegar, pers. comm. 1982) show that juniper removal can result in development of summer streamflow, despite the development of riparian communities, and also suggest that pseudoriparian plants can be greater users of water. Removal of deep-rooted, woody, pseudoriparian vegetation may have the best potential to increase water yield (Rowe 1963). Removal of true riparian vegetation exposes moist streambanks to increased insolation and evaporation, while replacement of peripheral woody plants with grass should significantly reduce transpiration without greatly increasing evaporation from drier-site soil surfaces. Evaporation may be a more important factor in water loss from small streams than is generally supposed (Lewis 1961). Interception of subsurface flow by pseudoriparian plants could be another factor affecting streamflow. Subsurface flow of snowmelt and storm water must travel under the areas peripheral to the riparian zone first, and could be largely transpired before reaching the riparian zone. In California, immediate increases in the flow of springs upon removal of deep-rooted, upland shrubs above springs were reported (Biswell and Shultz 1958), and the researchers postulated this vegetation was able to tap deep, underground flows of water which would otherwise have fed the springs. Besides shading and maintenance of a moist microclimate, riparian vege- tation provides structural materials for beaver dams and debris jams, and also the most important foods for beaver. Other suggested water-conserving functions of true riparian vegetation include the building of organic soils better able to retain soil moisture (Marcuson 1977), provision of litter which helps seal dams, and streambank stabilization preventing channel degrada- tion and loss of water table. During overbank flows, riparian vegetation helps slow and spread flows and may encourage better streambottom aquifer recharge. While removal of riparian vegetation may result in small increases in summer streamflow over the short term, the elimination of woody riparian vegetation and debris over the long term may result in eventual loss of summer streamflow, especially along stream reaches susceptible to gullying. Livestock are seldom removed from large, intermittent stream sections where unexpected flow increases would be likely to be noticed simply by eye, and this may explain why more reports of streamflow increase after removal of livestock are not available. Mechanisms by which summer flow increase might result upon removal of livestock may be hypothesized. Combined utili- zation of riparian vegetation by beaver and livestock may lead to the vir- tual elimination of wood, beaver, and their darns. By removal of livestock, 69