Balancing the Timber Budget 



^$>- 



TO MANAGE any business in an orderly way, one 

 must find some sort of balance between income 

 and outgo. With a forest resource, the growth 

 must be balanced against the timber cut. And losses 

 by fire, storm, insects, and diseases must be taken into 

 account. 



To find out how well the timber budget is balanced 

 in New Hampshire, estimates of growth and timber cut 

 were made. Since no previous survey plots were avail- 

 able for remeasuring, the estimates of growth were 

 based on increment borings of living trees. These esti- 

 mates are tentative. 



Estimates of Growth 



Three elements of net annual growth were esti- 

 mated : ( 1 ) The annual increase in net volume of the 

 trees that make up the growing stock at the beginning 

 of the year; (2) the ingrowth — that is, the volume of 

 saplings that grow to pole size (5.0 inches d. b.. h.) 

 during the year and thus become part of the growing 

 stock; (3) a deduction for the volume lost by mortality 

 during the year. 



The growth of cull trees and the increase in limb- 

 wood volume were ignored. Except for ingrowth, the 

 growth of seedlings and saplings was not counted. 

 Tree mortality was estimated from examination of 

 trees already dead when the plot was measured. It is 

 admittedly the weakest part of the growth estimate. 



The net annual growth of the forest growing stock 

 in New Hampshire in 1948 was estimated at 187 mil- 

 lion cubic feet (table 6). This is about 2.3 million 

 cords. By 1952 the net annual growth of growing 

 stock had increased to an estimated 212 million cubic 

 ■feet (table 7). 



Of course most of this volume was growth on the 

 initial growing stock. But ingrowth is an important 

 item: more than one-fourth of the total growth was 

 ingrowth. Hardwoods accounted for 57 percent of 

 the net growth in 1948. In 1952 the hardwood net 

 growth was estimated at 62 percent of the total. 



The net annual growth of sawtimber in 1948 

 amounted to 456 million board-feet — just short of 100 

 board-feet per acre of commercial forest land. In- 



growth — the volume of poletimber trees that grow to 

 sawtimber size during the year — was nearly two-fifths 

 of the total. Although the net growth of softwood 

 sawtimber has decreased, the increased growth of hard- 

 wood has more than offset this. The total net annual 

 growth of sawtimber in 1952 was 472 million board- 

 feet, 55 percent softwood and 45 percent hardwood 

 (table 7). 



The distribution of the net annual cubic-foot growth 

 among species was as follows in 1948: spruce and- fir 

 of all sizes, 15 percent; white pine sawtimber trees, 



Table 6. — Components of net annual growth on commercial forest land 

 of New Hampshire, by species group, 194S 



Item 



Softwoods 



Hardwoods 



All species 



Growth on initial growing stock 



Ingrowth (saplings that become 



Thousand 

 cubit feet 

 67,800 



17, 500 



Thousand 



cubic feet 



77, 600 



34,700 



Thousand 

 cubic feet 

 145,400 



52, 200 







Total 



85, 300 

 4,800 



112,300 

 5,500 



197, 600 





10, 300 









80, 500 



106, 800 



1S7, 300 







T.-^BLE 7. — JVet annual growth on commercial forest land of New 

 Hampshire, by tree-size class and species group, 1952 



Tree-size class and species group 



Sawtimber 



Growing 

 stock 



Sawtimber trees: 



Thousand 

 board-feet 

 259, 000 

 213,000 



Thousand 

 cubic feet 

 53,000 



Hardwood _- -_ 



56,000 





Total - _ 



472, 000 



109,000 





Poletimber trees: * 



Softwood - - 





27,000 







76,000 









Total 





103, 000 









Sawtimber and poletimber trees: 



259, 000 

 213,000 



80,000 



Hardwood 



132,000 







Total 



472, 000 



212.000 







^ Softwood trees lU inches d. b. h. are classed as sawtimber trees; hardwood 

 vrees of this diameter are classed as poletimber trees. Ingrowth of sawtimber 

 trees, of course, is a deduction from growth of poletimber trees. 



22 



Forest Resource Report No. 8, U. S. Department of Agriculture 



