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or elimination by overgrazing. In such cases, a plant species such as willow continues to exist in a plant community subject to heavy grazing because of beaver-created isolation from livestock caused by flooding. If beaver are removed from the stream and the ponds recede, these plants become vulnerable once again and can rapidly be eliminated from the plant community. Beaver in some circumstances have created elevated meadows through the deposition of sediments over several generations of ponds. This has perched the meadow higher than the geologic knick point eleva- tion. Streambanks formed through old beaver activity are generally low in bank rock content and are sensitive to mechanical damage. Heavy grazing can result in streambank collapse, accelerated meandering, enlarged chan- nels, and losses of most stream dependent resources. As a consequence, the loss of beaver in these circumstances can lead to the lowering of water tables and ultimately lead to the change from a mesic meadow type to a more xeric plant community, thus resulting in reduced forage pro- duction (Munther, 1981). In contrast, the amount of forage flooded by beaver ponds is more than compensated for in many cases by the increased production of adjacent lands resulting from higher water tables. Stand structure of aspen, cottonwood, or other hardwoods in or adja- cent to riparian areas can be altered by beaver in search of food. Large percentages of stands adjacent to ponds are cut down, particularly within 300 feet of water (Yeager and Rutherford, 1957). Once cut, many species can rapidly regenerate by suckering. However, if the suckers are contin- ually grazed heavily by livestock, a stand of trees can be prevented from successfully regenerating. This ~cenario has lead to loss of aspen groves and cottonwood stands in western Montana. Timber Management Active timber management in or adjacent to riparian areas has the potential to affect beaver distribution through the successional pattern resulting from timber harvest. silvicultural prescriptions that favor early successional stages composed of deciduous shrubs or hardwoods can be beneficial in creating a food supply appropriate for beaver. This food supply, in combination with suitable stream size and channel conditions is the primary component of beaver habitat. In contrast, uneven age management of conifer stands in riparian areas does little to create large amounts of beaver food. Timber management options are viable management techniques to influence beaver distribution. Conservative prescriptions such as individual tree selection or salvage prescriptions are usually detrimental to beaver, while clearcuts or group selection prescriptions are more favorable. Fire Management The management of fire greatly influences the food supply of beaver, particularly in habitat types with successional stages favoring conifers. Without treatments of these habitat types to create earlier successional stages, large amounts of beaver forage plants are eventually lost to seral stages favoring conifer stands. Some wetter riparian habitats in major 76