GLOSSARY 



Animal Unit Month (AUM): The number of animals times the number of months they graze. 

 An "animal unit" is a cow with calf 



Biodiversity: The variety of life and its processes. It includes the variety of living organisms, 

 the genetic differences among them, and the communities and ecosystems in which they occur. 

 (From Keystone Center) 



Closed road: A road that exists but is not open to vehicle traffic because of gates, berms, or 

 other man-made obstructions. 



Cumulative effects or impacts: The impact on the environment that results from the 

 incremental impact on an action when added to other past, present, and reasonably foreseeable 

 future actions regardless of what agency or person undertakes such actions. Cumulative effects 

 or impacts can result from individually minor but collectively significant actions taking place 

 over a period of time. 



Endangered Species: A plant or animal species whose prospects of survival and reproduction 

 are in immediate jeopardy. Its peril may result from one or many changes: loss of habitat or 

 change in habitat, overexploitation, predation, competition, disease, or even unknown reasons. 

 An endangered species must have help, or extinction may follow. It must be designated in the 

 Federal Register by the appropriate Secretary as an "endangered species." (Schwarz et al. 1976) 



Endangered Species Act (ESA): The Act that required consultation with the Fish and Wildlife 

 Service (Interior) if practices on National Forest System lands may impact a threatened or endan- 

 gered species (plant or animal). Direction is found in FSM 2670. 



Forest Health: A condition for forest ecosystems that sustains their complexity while providing 

 for human needs. In terms of ecological integrity, a healthy forest is one that maintains all of its 

 natural functions. In relation to management objectives, forest health represents a condition 

 which meets current and prospective future management objectives. (After O'Laughlin et al. 

 1993, Monnig and Byler 1992) 



Habitat Type: A collection of land areas potentially capable of producing similar plant 

 communities at climax, generally named for the predicted climax community type. (After Pfister 

 etal. 1977) 



Hydrology: A science dealing with the properties, distribution, and circulation of water, 

 specifically the study of water on the surface of land, in the soil and underlying rocks, and in the 

 atmosphere, with respect to evaporation and precipitation. (After Webster 1963 In: Schwarz et 

 al. 1976) 



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