Coulter, E.D.  1999.  Hungry Bob harvest production study: mechanical thinning for fuel reduction in the Blue Mountains of northeast Oregon.  M.S. Thesis.  Oregon State University, Corvallis, OR, 96 pages.

Mechanical thinning is an important tool for fuel reduction because it removes material from the site.  Thinning produces a saleable product, but the economics of the operation are important because it is difficult to make a profit.

This study looked at the cost of operating different kinds of machinery for thinning a 409-acre unit of ponderosa pine and Douglas fir.  Productions studies were conducted on three feller-bunchers and three forwarders.  The material removed included sawlogs and pulp.

FELLER-BUNCHERS:

 

Rottne SMV Rapid EGS

John Deere 653E

Caterpillar 320L Excavator

Relative cost of operation

65%

83%

100%

Sensitivity to travel distance between trees

High

High

High

Sensitivity to species composition

Low

Low

Low

Sensitivity to standing or down dead

Low

Low

Low

Sensitivity to tree diameter

Low

Moderate

High

Relative cost to harvest 4” diameter stems

55%

80%

100%

Relative cost to harvest 8” diameter stems

64%

81%

100%

FORWARDERS:

 

Timbco TF815-C

Rottne Rapid

Rottne SMV Rapid

Relative cost of operation

94%

100%

100%

Sensitivity to number of stops

Moderate

Moderate

Moderate