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stands, such as spruce/fir, only burn in holocaust conditions in western Montana. Some experts have estimated that this type of riparian area may have burned once every 400 years under natural conditions (Robert Mutch, personal communication). Therefore, fire management plans and prescriptions can ultimately influence beaver distribution. Fire manage- ment plans currently tend to favor low risk burning conditions and call for full scale suppression in conditions that would create these holo- caust burns. Under this management scheme, we can expect beaver to con- tinue to decline in distribution in these kinds of habitat. Prescrip- tions or plans favoring intense burns in riparian areas would be expected to favor beaver habitat in the long run. Transportation Systems Beaver activities frequently threaten to damage transportation facil- ities in and adjacent to suitable riparian environment areas. In many cases, these facilities were constructed in a period of beaver inactivity; therefore, no special design considerations were incorporated. Stream crossing structures, particularly if they constrict the channel width, are often incorporated as part of a beaver dam. In other circumstances, roadbeds become saturated as a result of the higher water tables created by beaver ponds. The most common outcome of this situation is to dili- gently remove the beaver colony. Removal of the problem beaver is, at best, a temporary solution. Longer lasting solutions are available. Several devices have been installed to prevent culvert blockage, and road- beds can be raised or reconstructed to improve drivability. Preventive transportation design effort appears to be the most effective tool in pro- viding compatible transportation facilities with beaver habitat and beaver activity. Avoidance of beaver habitat is often feasible by relocating a stream crossing to a steeper gradient stream reach. Roads placed a few feet higher on the slope above the riparian zone can eliminate the possi- bility of saturated roadbeds. Stream crossing structures that are wider than the channel width are less likely to become sites for beaver dams. Failure to design for beaver activity in beaver habitat will usually lead to expensive maintenance or elimination of the beaver resource. ASSESSING FOREST OBJECTIVES WITH RESPECT TO BEAVER Once the land manager or decisionmaker understands the relationships of beaver to other resources, he or she can begin to evaluate the positive or negative effects that beaver activity may have on his or her objectives. One approach can be passive, accepting beaver activity when it occurs and adjusting other land uses to be compatible with beaver. This form of management accepts beaver as a natural part of the ecosystem and adjusts Forest programs accordingly. A more active management approach is to plan beaver activity as a management tool to improve wildlife, fisheries, or recreation resources or to reduce impacts of other resource uses such as regeneration timber harvest, prescribed burning riparian areas, or planting of food species such as willows. Beaver populations are then manipulated to provide the direct and indirect benefits that meet the manager's objectives. 77