burning is permitted for forestry purposes only. No burning is allowed from 

 December 1 to February 28. The Montana DNRC is a member of the 

 Montana-Idaho Smoke Management Group. This group is composed of the 

 major forestry burners in Idaho and Montana. Members of the group report 

 their planned bums to a monitoring unit in Missoula before they are ignited. 

 The goal of the smoke monitoring unit is not to allow the average PM-10 level 

 for a 24 hour period to exceed 50 milligrams per cubic meter of air. Idaho and 

 Montana are divided into "airsheds" which are geographic areas with similar 

 topography and weather patterns. Urban areas within airshed are designated 

 as impact zones. Due to the potential for adverse impacts to air quality in 

 urban areas, burning in these impacts zones is much more restrictive than the 

 airshed it is located in as a whole. The project area is located in Airshed 3A 

 and the Missoula Impact Zone as designated by the Montana/Idaho Airshed 

 Group. The Montana/Idaho Airshed Group Monitoring Unit issues daily 

 smoke dispersion forecasts and burning restrictions for each airshed and 

 impact zone. Restrictions are based on the number of bums planned, their 

 location and atmospheric conditions. These restrictions are designed to limit 

 the adverse impact to air quality resulting from prescribed buming. 



3.2.6 Noxious Weeds (Issue #6) 



Noxious weeds, including hounds tongue (Cynoglossum officinale), sulfer 

 cinquefoil (Potentilla rectre), spotted knapweed (Centaurea maculosa), spots of 

 thistle (Cirsium arvense) and leafy spurge {Euphorbia esula) occur within the 

 analysis area. Knapweed is well established along the existing road systems and 

 areas with past harvest activities. Leafy spurge is wide spread throughout the SE 

 '^ of Section 16 and the SW % of Section 15. 



3.2.7 Natural Forest Conditions (Issue #7) 



The habitat types (h.t.) in the project area all belong to Fire Group 6 as defined by 

 (Fischer and Bradley 1987). Douglas-fir is both the indicated climax species and a 

 vigorous member of the serai component. It is not uncommon for Douglas-fir to 

 dominate all stages of succession. Ponderosa pine, western larch and lodgepole 

 pine are serai components whose abundance varies by phase. Fire history studies 

 conducted with the PSME/CARU h.t. in southwest Montana indicate a mean fire 

 interval of 42 years, for pre European-settlement stands. A tentative mean fire- 

 free interval of 15.8 years was reported within a PSME/PHMA h.t. near Missoula, 

 Montana. Fire was an important agent in controlling density and species 

 composition. Low to moderate severity fire converted dense stands of pole-sized 

 or larger tress to a more open condition, and subsequent light buming maintained 

 stands in open conditions. Frequent low or moderate fires favored larch and 

 ponderosa pine over Douglas-fir where these species occurred. Severe fires 

 probably occurred on dense, fuel-heavy sites and resulted in stand replacement. 

 Stand replacement fires favored lodgepole pine on sites where this species was 

 present. Fire's role as a stand replacement agent becomes more pronounced when 

 the natural fire-free interval is increased though fire suppression, unless 

 corresponding fuel reduction occurs. The theoretical climax condition on Group 



Deadman Gulch Timber Sale Environmental Assessment 3-8 



