declines in populations across the northwest. Continued drought and overstocked stand 

 conditions may lead to an increase in numbers over the long term. 



2. Dwarf Mistletoe: Dwarf mistletoe would continue to be present and increase numbers 

 of infected trees without disturbances to eliminate all or some currently infected trees. 

 The infection would continue to be spread from infected overstory to adjacent overstory 

 and understory trees. Reduced growth rates and tree vigor would persist as infection is 

 spread from the overstory to younger regeneration below, resulting in long term 

 merchantable timber quantity and quality reductions. Long-term infection would cause a 

 gradual shift in species composition from serai species such as western larch to more 

 shade tolerant species such as alpine fir and grand fir. 



3. Root Diseases: Root diseases would continue to be present causing mortality in the 

 overstory and understory. Root disease centers would continue to increase in size over 

 time. These pockets may regenerate with less susceptible species such as western larch, 

 but more than likely will regenerate with susceptible species such as Douglas-fir and 

 grand fir which have higher reproductive success. The perpetuation of the root disease 

 susceptible species would result in loss of timber productivity around these sites until less 

 susceptible species become established. 



Action Alternative : 



1. Bark Beetles: Lodgepole pine trees, within proposed harvest units, would be 

 salvaged. Salvaging lodgepole recently infected with beetles can interrupt the beetles 

 breeding cycle and result in reduced tree mortality. Under the action alternative, basal 

 area reductions resulting from timber harvest would increase vigor and growth in 

 remaining trees that are susceptible to mountain pine beetle attack. Increases in growth 

 and vigor improve the tree's ability to "pitch out" attacking beetles and survive. 



2. Dwarf Mistletoe: Western larch infected with dwarf mistletoe would be harvested 

 under the action alternative. Reduction in infected overstory trees will remove sources of 

 mistletoe infection and reduce fiiture losses in growth and yield. Promotion of healthy 

 western larch overstory and supplemental planting of areas severely infected with 

 mistletoe with western larch would provide long-term growth and yield. 



3. Root Diseases: Douglas-fir would be salvaged around root disease pockets, although 

 rates of disease spread and tree mortality will not be reduced. Silvicultural prescriptions 

 will favor retention of species less susceptible to root disease, improving friture stands 

 resistance. 



2. Cumulative Effects 



No Action Alternative : Insect and disease populations under the no action alternative 

 would remain static to increase over time. Bark beetles would continue to increase in the 

 short term and depending upon drought and stocking conditions, continue to increase for 

 a period of time until their life cycle is disrupted. Dwarf mistletoe infection in the larch 



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