observed that skidding of coarse-limbed ponderosa pine was 

 more effective than skidding of finer branched species. Also, 

 soil conditions can be critical. Certainly, skidding on frozen or 

 snow-covered soils will produce little scarification. The Arkan- 

 sas Creek block was harvested in August during a Douglas-fir 

 seed year. Scarification was excellent. The following growing 

 season was moist. Due to this fortunate combination of events, 

 it appears that adequate natural regeneration has occurred. 

 Figure 10 provides a comparison of before and after harvesting 

 conditions on some of the harvest blocks. Slash treatment was 

 not necessary on any of the blocks harvested. 



It is a well-known fact that risk of insect attack is increased 

 when partial cutting ponderosa pine stands, due to the im- 

 proved breeding conditions for Ips bark beetles (Ips pini) in the 

 accumulation of green slash. Whole-tree utilization definitely 

 eliminates this problem. Only minor amounts of slash consist- 

 ing of fine branches that quickly dry and become unsuitable 

 habitat for bark beetles are left in the stand. 



Whole-tree utilization eliminates piling and burning. 

 On the experimental logging blocks, one or two slash piles on lan- 



dings were burned. These were made up of fine branches, soil, and 

 stones. It was not considered worth the damage to chipper knives 

 to process the material. 



Air pollution due to slash burning is of concern in the study 

 area. Air temperature inversions in the mountain valleys often 

 limit the number of days when burning can be accomplished. 

 Therefore, reduction in the total amount of material to be 

 burned is a definite advantage for this harvest system because it 

 reduces the cost of burning dependency on suitable weather 

 and fuel conditions. 



Stand access for current and future harvests was definitely 

 improved by the use of feller-bunchers. The low stumps greatly 

 reduced skidding problems. Also, smaller material that is nor- 

 mally pushed over during skidding was chipped for hog fuel. 

 Elimination of the small trees also facilitated the skidding. 



Visual impact of logged areas, especially along heavily trav- 

 eled routes, is often a major concern. The appearance of all the 

 blocks harvested by this system was esthetically satisfactory. 

 This harvest system could probably be used in visually sensitive 

 areas. 



11 



