INTRODUCTION 



The forester of today must increase the supply of wood fiber from a shrinking tim- 

 berland base while minimizing environmental damage, aesthetic disturbances, and fire 

 hazards. One important method for accomplishing these objectives is to utilize more of 

 the residue resulting from treatments of mature stands. 



Although forest industries in the Northern Rockies are obtaining an increasing 

 amount of raw wood from residues formerly abandoned or burned, volumes and characterists 

 of this material and prospects for additional wood utlization are largely unknown in 

 mixed conifer types of north Idaho. Little quantitative data is available on the efforts 

 expended and results of adopting stringent utilization standards. 



This report describes experimental relogging of two State of Idaho (Department of 

 Lands) timber sales in the mixed-conifer type of north Idaho. The relogging was con- 

 ducted in July and August of 1975. Both sales had been conventionally harvested within 

 one year of the relogging. The study was intended to answer the following questions: 



1 . What are the volume and characteristics of logging residue after conventional 

 logging? 



2. What additional products and wood volumes could be removed in a relogging 

 operation imposing stringent utilization standards? 



3. What are the residue volumes and characteristics after relogging? 



4. What relogging production rates might be expected using equipment common to 

 north Idaho? 



The study revealed that logging residues can be reduced approximately 40 to 60 

 percent in cubic volume, and significant quantities of useable raw wood can be recover- 

 ed by imposing logging standards more stringent than normal. Relogging production 

 rates were dependent on machine condition, capacity, and flexibility as well as site 

 conditions and residue characteristics. Economic feasibility of relogging which de- 

 pends upon the prevailing market for small logs and pulp bolts, was beyond the scope of 

 this study. 



THE STUDY AREAS 



Selection of Study Areas 



During the spring of 1975, six recently logged areas representing the mature, 

 mixed-timber types of north Idaho were selected for preliminary residue measurments. 

 A cutting block on each sale was transect-inventoried to determine residue character 

 and volume. Comparison of timber sale statistics and transect survey results provided 

 the basis for estimating amounts of wood harvested and residues. The range of stand 

 conditions utilization standards, and residue amounts are presented in appendixes I and 

 II to allow the interested reader to make generalizations concerning his own situation. 

 The following criteria were used to select the study areas. 



1. Utilization standards of sale and logging methods 



2. Silvicultural treatment 



3. Sale volume per acre 



1 



