A SUMMARY OF THE TIMBER RESOURCE REVIEW 



95 



passage of time western species will make up an 

 increasing proportion of growth but a decreasing 

 proportion of timber removal and of inventory. 

 The differences between needed growth and 

 timber removal by species groups are less in 2000 

 than in 1975, showing that progress is assumed in 

 achieving necessary inventory adjustments but 

 that the adjustment is not fully completed. 

 Eventually timber removal and needed growth 

 should be the same not only for national totals 

 but for each species group. 



Adjustments in Inventory Are Needed 



Considering only national totals, the changes 

 in sawtimber inventory needed in 1975 or 2000 to 

 sustain needed growth are not so pronounced in 

 relation to 1953 as were needed growth adjust- 

 ments. Total sawtimber inventory could adjust 

 downward to meet either lower or medium timber 

 demand in 1975 and to meet lower timber demand 

 in 2000 (table 59). To meet medium timber 

 demand in 2000, however, about a 36-percent 

 increase in sawtimber inventory over 1953 is 

 projected. On a per capita basis, decreases in 

 sawtimber inventory are shown for both 1975 and 

 2000, and for both lower and medium timber 

 demand. 



The above overall indications may be partic- 

 ularly misleading with respect to inventory 

 adjustments unless species groups are considered. 

 An analysis by species groups shows that changes 

 in needed sawtimber inventory would be both at 

 different rates and in different directions than 

 changes in needed growth. Eastern softwoods, 

 for exam.ple, show that upward adjustments in 

 inventory must be much greater than the needed 

 adjustments in growth. Eastern softwood in- 

 ventory needs to increase 300 percent by 2000 to 

 meet the medium projected timber demand in 



Table 59. — Relation of needed sawtimber inventory 

 to 1953 inventory 





Change in inventory from 1953 inventory 



Species group 



1975 



2000 





Lower 

 projected 

 demand 



Medium 

 projected 

 demand 



Lower 

 projected 

 demand 



Medium 

 projected 

 demand 



Eastern hardwoods. 

 Eastern softwoods. 

 Western species 



Percent 



-6 



+ 86 



-58 



Percent 



+ 27 



+ 162 



-52 



Percent 



+ 32 



+ 147 



-45 



Percent 

 + 102 

 + 301 

 -26 



All species 



-32 



-12 



-8 



+ 36 



Per capita 



-50 



-36 



-47 



-22 



contrast to a needed increase of 154 percent in 

 growth. On the other hand, western species show 

 that inventories could decrease while growth needs 

 to increase. 



There are several reasons for these differing 

 rates and directions of change as between needed 

 inventory and needed growth. The reasons also 

 explain why the total inventory adjustment for all 

 species combined is in several instances downward. 

 Eastern softwood inventory of course must be 

 built up to higher levels to sustain the increase in 

 needed growth. On the other hand, western old- 

 growth softwood sawtimber stands must, after 

 harvesting, be replaced by young growth well dis- 

 tributed as to age classes. This young tiro.ber will 

 have much less inventory volume but will sustain 

 much higher growth than is now the average in 

 the West with the substantial acreage of old- 

 growth stands supporting large volumes and little 

 or no growth. Both the building up of eastern 

 softwood inventory and better distribution of age 

 classes of western softwood inventory through 

 orderly harvesting and reduction of old growth 

 are essential in order to produce on a sustained 

 basis the growth needed. 



In terms of growing stock, needed adjustments 

 indicate inventory increases in eastern softwoods 

 and decreases in western species for both medium 

 and lower timber demand in both 1975 and 2000. 

 Total growing-stock inventory would need to in- 

 crease only to sustain the medium demand in 2000. 



Needed inventory in relation to both 1953 

 inventory and projected inventory (discussed 

 later) is shown in table 60 by species groups, by 

 sawtimber and growing stock, for both lower and 

 medium timber demand, and in 1975 and 2000. 

 The most significant inventory needs are that 

 eastern softwood sawtimber inventory should in- 

 crease four times by 2000 to meet medium timber 

 demands and the western softwood inventory 

 should decrease by 25 percent if accompanied by 

 proper adjustment in age classes. If such changes 

 were to occur, they would mean that eastern soft- 

 woods instead of making up 12 percent of the saw- 

 timber inventory of the Nation as in 1952 would 

 increase to 35 percent by 2000. Western species 

 correspondingly would drop from 70 percent of the 

 total sawtimber inventory to 38 percent of the 

 total (table 58). 



Projected Growth and Inventory 



Estimates of the growth and inventory needed 

 to sustain future demands and the relation of this 

 needed growth and inventory to 1952 have just 

 been summarized. A much more significant com- 

 parison, however, is the relationship of needed 

 growth and inventory to the growth and inventory 

 that might be expected in 1975 and 2000 if rising 

 timber demands are met each year and if recent 



430296 O— 58 



