Old growth sawtimber stands had an average of 7,000 net board feet 

 Scribner per acre. Young growth sawtimber stands averaged 4,200 net board 

 feet Scribner per acre. The average number of trees per acre by diameter 

 class and stand size class (see Table 59 in Appendix 3) indicates most of the 

 old growth sawtimber stands, and to a lessor degree the young growth saw- 

 timber stands, are uneven-aged. If the distribution by diameter class for 

 young growth sawtimber stands is analyzed along with the understocked 

 nature of these stands and the excessive age of many of the smaller diameter 

 trees, an unfavorable silvicultural picture begins to unfold. To optimize 

 timber production, many of these stands need to be harvested and started 

 over when it becomes economical to do so. 



Past Harvest Rates and Growth 



Data covering a 15 year period shows timber harvesting has fluctuated but 

 generally increased on private lands from 1970 to 1980. The average amount of 

 timber harvested annually on private land in Working Circle 3 over 15 years 

 was 88.'* million board feet. Powell County supplied k^ percent of the total 

 volume harvested from private lands during the period. The annual average 

 harvest from private land over the last 15 years is only slightly higher than 

 the board foot net growth estimated for 1978. 



Each year, the Forestry Division attempts to determine the amount of 

 timber harvested on state and private lands. This amount is determined from 

 state land records and hazard reduction agreements drawn between the state 

 and logging operators. The board foot volume listed in Table 47 shows the 

 amount of timber loaded on trucks and delivered to mills. Normally, the 

 smallest trees delivered are in the 6-inch diameter class. In addition to the 

 volume brought to the mills, a portion of the merchantable volume is left in 

 the forest as logging residue. Based on figures reported by the USDA 

 Forest Service for western Montana and northern Idaho (Wilson et al. 1970), 

 the amount of residue left on the logging site is about 7 percent of the board 

 foot volume delivered to the mills. Timber is also harvested for railroad ties, 

 posts, poles, rails, and firewood (cord wood) but the amount of timber har- 

 vested for these uses is small compared to the amount harvested for other 

 forest products. 



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