Table 9 . - -Produotion surmary 



Skidding Method 



Item 



Skidder 



Horse 



Tractor 



Residue vol . /acre-ft^ 

 Product vol . /acre-ft^ 

 Post material-% total 

 product vol. 



908 

 1,125 



66 



1,487 

 726 



71 



1,103 

 757 



75 



Man-days/acre 6.8 9.7 6.9 



% of skidder 100 143 101 



No. pcs/8 h day 168 125 112 



% of skidder 100 74 67 



V0I./8 h day-Cunit 7.95 6.21 5.05 



% of skidder 100 78 64 



Skidding Cost/cunit-$ 10.18 12.48 15.70 



% of skidder 100 123 154 



CONCLUSIONS 



Residue Reduction 



Table 9 summarizes the study data. Although the top of table 9 is related to 

 utilization standards rather than skidding methods, it shows the residue volumes that 

 resulted. Assuming that the post material would probably be logging slash on a 

 conventional harvest, at least 66 percent of the total products removed from the area 

 would have been slash. Or, through increased utilization the logging residues were 

 reduced to one-third or one-half times what might have been left. Logging residues 

 have been reduced further because of the treetops hauled from the logging site, much o 

 which became yard residues. Tables 2 and 4 show: 



Initial Volume 36,754 (table 2) 



Standing 15,674 

 Down 21,080 



Volume removed 20,883 (table 4) 



Products 12,208 

 Yard residue 8,675 



The additional 8,675 ft' of material removed that was unsuited for solid wood products 

 represents 24 percent of the total initial volume or 42 percent of the total material 

 removed. The value of this material depends upon local markets. At the time of the 

 study the post market was very good. Some of the material classed as unusable was 

 used for small, electric-wire fenceposts and small, class 5 fenceposts. A large part 

 of the material was disposed of as free firewood. During periods of tight chip 

 supplies, the material could be chipped. 



15 



