Although only one horse at a time was used for skidding, the operators had a 

 relief horse, and horses were changed approximately every 2 hours. Generally, on a 

 gross time basis, skidding was carried on for about 6 hours per day. One operator 

 worked his horses from 7:00 a.m. until 3:00 p.m., with two half-hour rest periods and 

 a one-hour lunch break. The other operator worked 8:30 a.m. until around 5:00 p.m., 

 with variable rest and lunch breaks. On an 8-hour workday basis, horse skidding cost 

 $77.52 per day or $12.48 per cunit. 



Tractor Skidding 



The tree felling operation for the tractor consisted of cutting the trees at ground 

 level and pushing them uphill. Bucking that was necessary to meet legal load length 

 was done on the truck rather than on the logging unit. (The hooking, bunching, skidding, 

 unhooking, and landing operations were similar to the rubber-tired skidder operations.) 



The tractor was a 25 hp John Deere Model 420, which is a fairly common size for 

 light ranch work in the area. The operator was the same person who operated the rubber- 

 tired skidder. Thus, it is reasonable to assume that the nonoperating functions would 

 be closely comparable for both methods. Also, the differences in travel times should 

 be free of operator performance differences. At a cost of $79.26 per day, the track 

 skidding cost $15.70 per cunit. 



STUDY RESULTS 



Inventory of wood on the units prior to harvesting, measurement of material re- 

 moved, and reinventory of the units after harvesting provide a basis for describing 

 utilization, product recovery, and residue remaining. 



Harvesting Statistics 



Harvest volume is the total cubic volume skidded to the landing. Except for 

 approximately 126 ft^ of fuelwood left in a cold deck, all the material skidded to the 

 landing was loaded out and hayled to a sawmill or post and pole plant. This material 

 was classified as green or as dead. Table 4 shows the material removed from each unit, 

 and material remaining as residue on the site. Figure 2 is a distant view of unit 4 

 (right) and unit 5. Figures 3 and 4 show closeups of residues on units 4 and 5, 

 respectively. 



Volumes of net usable material were determined from a computer program designed 

 to calculate products and volumes from each piece loaded out. Three inspections at 

 the log yard confirmed program reliability. 



"Yard residue" refers to the amount of cull, or nonutilized material, hauled to 

 the mill or post yard. Material removed from units 1 and 2 contained a large proportion 

 of unutilizable material, according to the program. Much of this "yard residue" was 

 disposed of as free firewood. 



The residue removal ratio compares the volume of yard residue to total (logging 

 plus yard) residues. A high ratio suggests a clean logging job. That is, logging 

 residues have been carried to the yard. The difference is illustrated by the high 

 product/residue ratio of 6.56 for unit 5. 



7 



