Unit 3. — All trees cut on this unit had a minimum d.b.h. of 

 9 inches (22.9 cm). Most trees were sheared using the feller- 

 buncher. Trees too large for the shearing head, including 25 

 green trees, were felled with a powersaw by the machine 

 operator. One skidder was used full-time, and a second, oper- 

 ated by a member of the landing crew, was used as needed. 

 Entire trees were skidded by the grapple-equipped farm tractor 

 to the landing where only saw logs were cut. The minimum top 

 diameter inside bark (d.i.b.) was 6 inches (15.2 cm). The 

 residue — branches and tops — was burned at the landing as it 

 accumulated. 



Unit 4. — This unit had essentially the same utilization standards 

 as unit III. Minimum d.b.h. of the felled trees was 9 inches 

 (22.9 cm). The trees on this unit were felled with a powersaw, 

 limbed, and bucked at the stump with preferred log lengths of 

 26.5 ft (8. 1 m) or 17.3 ft (5.3 m). The logging residue was piled 

 and burned in the stand. The skidder with chokers was used to 

 move the logs to the landing. 



On units I and III, the feller-buncher operator was the 

 primary skidder operator, did the powersaw felling, and was 

 crew supervisor. The landing crew was made up of three or 



four persons. The sawyer did the limbing and bucking; the 

 other crewmembers assisted with the limbing and bucking, did 

 the skidding and decking of logs and fenceposts, and moved 

 the residue to the chipper or bum pile. On units II and IV, a 

 one- or two-man crew was used. One man did the powersaw 

 felling, limbing, and bucking with some help cutting posts at 

 the landing. The other crewmember operated the skidder. 

 The unit procedures are summarized in table 1 . 



Results and Discussion 



The small size of the study units, 2.5 acres (I ha), precluded 

 continuous operation of all the machines. The feller-buncher 

 completely felled and bunched the trees on one unit in less than 

 6 hours and the work on units I and III required less than 

 1.5 days. However, more than 2 days were needed to skid the 

 trees on these units. 



The tree felling data are presented in table 2. As would be 

 expected, use of the feller-buncher was much faster than use of 

 powersaws. The smallest number of trees was cut on unit III, 

 which also had the greatest production rate. 



Table 1.— Summary of the procedures and utilization standards for the four study units 



Unit 



Item 



1 



II 



ill 



IV 



Objective 



Sanitation 



Thinning 



Saw log removal 



Saw log removal 





salvage 









Prescription 



Cut all 



Leave basal 



Cut all 



Leave basal 





infested 



area 110 ft' 



infested trees 



area 110 ft' 





trees 









Thinning 



Precom- 



Commercial 



Commercial 



Commercial 



alternative 



mercial 









Felling 



Shear 



Powersaw 



Shear 



Powersaw 



Limb and buck 



Landing 



Landing 



Landing 



Stump 



Skid 



Grapple 



Choker 



Grapple 



Choker 



Residue 



Chip 



Chip 



Burn at 



Burn at 



treatment 







landing 



stump 



No. in crew 



3 



1,2 



3,4 



1,2 







UTILIZATION 





Size skidded 



Full tree 



Full tree 



Full tree 



Log length 



Min. d.b.h. 



1 " (2.5 cm) 



9" (22.9 cm) 



9" (22.9 cm) 



9" (22.9 cm) 



Top d.i.b. 



3" (7.6 cm) 



3" (7.6 cm) 



6" (15.1 cm) 



6" (15.1 cm) 



Products 



Saw logs 



Saw logs 



Saw logs 



Saw logs 





Posts 



Posts 









Chips 



Chips 







Table 2.— Tree felling production rates on the four study units using the feller- 

 buncher (shear) and powersaws 



Unit 



Item 



iV 



Method 



Shear 



Powersaw 



Shear 



Powersaw 



Hours per unit 



4.85 



11.75 



'2.65 



8.26 



Hours per acre 



1.94 



4.70 



1.06 



3.30 



Trees per hour 



88 



38 



69 



40 



'Does not Include time required to fell 25 trees using the powersaw 



3 



