Table 1.— Summary of study areas and production volumes 



Area 



Description 



Species mix 



Production 



i-log fuel 



Logs 



Percent 



Arkansas Creek 



20 acres (8.1 ha) 

 Slope 4% 

 Shelterwood 



Maximum skid 800 ft (0.24 km) 

 Haul distance 65 mi (104.6 km) 

 5 days 



PP 



WL 

 DF 



82 

 15 

 3 



333 units 

 1 load/acre 

 25 tons/acre 

 (56.3 t/fia) 



71.1 M bd.ft. 

 .9 load/acre 

 3.6 M bd.ft./acre 



Gold Creek 12.7 acres (5.1 ha) 



Slope 4% -25% 

 Clearcut 



Maximum skid 800 ft (0.24 km) 

 Haul distance 55 mi (88.5 km) 

 4 days 



PP 

 LLP 



2 

 98 



426 units 

 1.9 loads/acre 

 44.4 tons/acre 

 (99.9 t/ha) 



94.9 M bd.ft. 

 1.8 loads/acre 

 7.5 M bd.ft./acre 



Sunflower Road 4.5 acres (1.8 ha) WL 90 142 units 



Slope 25% LPP 7 2 loads/acre 



Commercial thin DF 3 43 tons/acre 

 Maximum skid 500 ft (0.15 km) (96.8 t/ha) 



Haul distance 55 mi (88.5 km) 

 2 days 



Sheep Flats 43.1 acres (17.4 ha) PP 80 607 units 



Slope 5% DF 20 0.9 load/acre 

 Shelterwood 19.4 tons/acre 



Max. skid 1,000 ft (0.30 km) (43.7 t/ha) 



Haul distance 70 mi (112.6 km) 

 9 days 



17.4 M bd.ft. 



.9 load/acre 

 3.2 M bd.ft./acre 



224.9 M bd.ft. 

 1.2 loads/acre 

 5.2 M bd.ft./acre 



Table 2.— Comparison of labor productivity for different logging 

 blocks 



Table 3.— Distribution of harvested cubic volume by size class 



Production 



Production rates 



Harvest block 



Fuel 



Logs 



Total 



Manhours 



Fuel 



Logs 



Total 







- Tons 







-Tons/man-hour ~ 



Arkansas Creek 



495 



471 



966 



339 



1.5 



1.4 



2.9 



Gold Creek 



564 



608 



1,172 



313 



1.8 



1.9 



3.7 



Sunflower Road 



193 



108 



300 



107 



1.8 



1.0 



2.8 



Sheep Flats 



903 



1,349 



2,252 



530 



1.7 



2.6 



4.3 



With respect to the first item, table 3 shows that the most 

 productive blocks (Sheep Flats and Gold Creek) had roughly 

 70 percent of the take volume in trees > 9 inches (22.9 cm) 

 d.b.h., and these trees accounted for 33 percent and 41 percent 

 of the total take stems, respectively. In contrast the least pro- 

 ductive blocks had roughly 60 percent of the take volume in 

 trees >9 inches (22.9 cm) d.b.h., but these stems were only 

 17 percent of the total take stems. Thus, the system was least 

 productive where the supply of saw log material was low 

 relative to the supply of chippable material. As with other log- 

 ging systems, stem size is an important productivity parameter. 



Percent of take volume Percent of take stems 

 Harvest block >9 " d.b.h. <9" d.b.h. >9 " d.b.h. < 9 "d.b.h. 



Arkansas Creek 

 Gold Creek 

 Sunflower Road 

 Sheep Flats 



64 

 70 

 60 

 72 



36 

 30 

 40 

 28 



17 

 41 

 17 

 33 



83 

 59 

 83 

 67 



The distribution of volume by size class also appeared to af- 

 fect productivity of the system through its effect on the system 

 operation. For example, the feller-bunchers could cut 5- to 

 15-inch (12.7- to 38. 1-cm) diameter trees in approximately the 

 same time. Thus, shearing time per cubic foot of production is 

 higher in stands with a large proportion of small stems than in 

 stands with mostly large stems. 



The log processor and chipper were also affected by the 

 relative proportion of large and small stems. Table 4 shows the 

 utilization rates for both machines. In the most productive 

 blocks (Sheep Flats and Gold Creek) the processor and chipper 

 had utilization rates of about 70 percent. In the Sunflower 

 block the utilization rate for the processor was only 36 percent . 



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