The number of trees taken from units I and II were 345 and 

 435, respectively. On unit III, 207 saw logs were produced. On 

 this unit, because the skidding tractor did not have a push 

 blade, the Farmhand tractor was used part-time to deck the 

 logs and move the residue into the fire. On unit IV, 339 logs 

 were skidded and decked conventionally at the landing. 



The whole tree chipper' s heel-boom grapple did not efficient- 

 ly handle tops and small stems, but the chipper was the only 

 one available. The objective of the chipping operation was to 

 determine chip volume and quality obtainable in this type of 

 operation. Production measures used were lineal feet of input, 

 (tops and small trees) and weight of chip output. Chip produc- 

 tion is shown in table 3. Average chip production for units I 

 and II was 1 1 .9 lineal feet/minute, 2.6 green tons/hour, and 

 0.9 dry unit/hour. This production was less than normal. In 

 other studies, a Morbark Model 12 and a Trelan Model DL-18 

 had produced 15 and 13.7 units (200 ft' each)/hour, respectively. 



As a result production data for a Morbark Eager Beaver 

 model were used for cost analyses. This chipper has a lineal 

 feed rate of 64.5 ft/minute, far exceeding the actual production 

 rate of 11.9 ft/minute. The operational cost of the Beaver chip- 

 per was $173.76/day, of which $50 was for the machine and 

 $123.76 for labor. 



Personnel utilization. — The interchanging of positions by the 

 crewmembers on units I and III caused some minor timekeep- 

 ing problems. Unaccounted time expressed as a percentage of 

 gross shift time is shown in table 4. 



Two observers, one at the landing and one in the woods, 

 were needed to time the skidding on units I and III. Unit III 

 required the most supervisory time. 



Potential productivity rates based on the time studies are 

 shown in table 5. The data show that on units I, II, and III, 

 the skidding rate determines the number of trees processed per 

 hour at the landing, and on unit IV the felling rate determines 

 the number of trees limbed and bucked per hour. 



The average time and standard deviation for the critical skid- 

 ding variables are shown in table 6. These data show the rela- 

 tionship between turns per hour, pieces per turn, and pieces per 

 hour. Units I and III had a high number of turns per hour and 

 a low number of pieces per turn due to the speed and low 

 capacity of the grapple skidder. The opposite held for units II 

 and IV, which had few turns per hour but a large number of 

 pieces skidded per turn. As expected, the volume skidded was 

 affected by the number of pieces and the average volume per 

 piece. The largest volume skidded per hour was on unit I; 

 unit II had the smallest volume skidded per hour. 



Table 3.— Various measurements of chip production 

 for units I and II 



Sum or 



Item Unit I Unit II average 



Gross time (hours) 



11.40 



13.65 



25.05 



Lineal feet 



9,177 



8,660 



17,837 



Lineal feet/minute 



13.47 



10.57 



11.87 



Tons 



31.87 



32.14 



65.01 



Tons/hour 



2.80 



2.35 



2.60 



Bone dry units 



12.3 



9.7 



22.0 



Bone dry units/hour 



1.08 



0.71 



0.88 



Cubic feet 



938 



1,209 



2,147 



Cubic feet/hour 



82.28 



88.57 



85.70 



Table 4.— Unaccounted time by unit as a percent of shift time 



Operation Unit I Unit II Unit III Unit IV 



Percent 



Woods 2 2 2 1 



Skidding 4 2 3 2 



Landing 2 2 4 1 



4 



