OPPORTUNITIES FOR INCREASING TIMBER SUPPLIES 



95 



Accelerated planting efforts, as in the case of 

 much current planting, will often require such 

 measures as clearing areas of economic size; 

 piling, chipping, disking, or burning logging 

 debris; bedding prior to planting to improve 

 drainage; chemical destruction of competing 

 vegetation; or combinations of such measures. 



Stand conversion. — Many areas in both the 

 East and the West Coast support poorly stocked 

 stands of hardwood trees of inferior species or 

 quality that can be expected to produce little 

 volume or value growth. Clearing of such stands 

 and planting to softwood is being done success- 

 fully on a rather wide scale on industrial and 

 certain other lands, and numerous opportunities 

 exist for expansion of such stand conversion 

 programs, especially in the South. Also, in the 

 case of certain stagnated stands of species such 

 as lodgepole pine in the West, removal of the 

 present trees and replacement by new stands of 

 the same or different species is the only way to 

 achieve full use of the site potential. Such con- 

 version in some areas, however, may be limited 

 by low sites or because of wildlife or other non- 

 timber considerations. 



Stand improvement. — Precommercial thinning 

 in the early years of the life of timber stands in 

 many cases has major impacts on timber yields. 

 Such thinning produces no immediate usable 

 wood but has its payoff in faster growth, shorter 

 rotations, more growth in usable trees and higher 

 quality wood. 



In most timber types individual trees assert 

 dominance over the others and stands develop 

 efficiently. In other cases, crowding becomes 

 progressively more serious and long rotations 

 are required to produce merchantable wood. At 

 its worst this crowding results in stagnation, 

 especially on poor sites, with resulting spindly 

 stands of small trees that never become merchant- 

 able — at least by prospective standards. 



Precommercial thinning of heavily stocked 

 stands is one of the major technical opportunities 

 for increasing yields in many forests. Other 

 measures that require out-of-pocket investments 

 to increase timber volumes and values include 

 removal of undesirable overstory trees in young 

 stands having sufficient "crop" trees to utilize 

 the site. 



Commercial thinning. — Cutting of merchantable 

 trees to improve spacing and stimulate growth of 

 crop trees is still a relatively limited practice in 

 the United States. Nevertheless, numerous re- 

 search studies indicate that commercial thinning 

 often can provide early returns, utilize material 

 otherwise lost as mortality, and concentrate 

 growth on the more valuable trees. This is particu- 

 larly the case on lands where production of saw- 

 timber is the objective of management. 



In reaching decisions as to thinning opportunities, 

 land managers in some cases must also consider 

 certain adverse factors, such as possible logging 

 damage to residual stands, increased fire hazards 

 from thinning slash, problems of access in moun- 

 tainous country, and problems of windthrow in 

 some areas. 



Salvage. — Harvesting of a larger portion of the 

 2.8 billion cubic feet of softwood timber killed 

 annual!}' by fire, insects, or other causes also 

 represents an important potential for increasing 

 log supplies in some areas. 



Fertilization. — As indicated in the previous 

 chapter, there has been increasing experience in 

 recent years in the use of forest fertilizers to 

 accelerate and improve tree growth. Most of the 

 activity in this regard has been in the Pacific 

 Northwest and in the South — practically all by 

 industrial owners. 



Experience suggests that timber yields can be 

 increased rather substantially with applications 

 of nitrogen and in some cases with other nutrients 

 such as phosphorus. "While adequate information 

 is not yet available on costs and benefits of 

 increased fertilizer application, it seems likely that 

 fertilization will prove to be economically attrac- 

 tive on millions of acres of productive forest 

 lands, particularly with increases in timber prices. 



Protection against insects and diseases. — As indi- 

 cated earlier, insects and diseases take a heavy 

 toll of timber by killing trees and by reducing 

 timber growth. The annual mortality and growth 

 reduction attributable to only three pests, for 

 example — western dwarf mistletoes, western bark 

 beetles, and southern pine beetles — alone are 

 estimated to equal about 13 percent of the current 

 timber harvest. 



A number of major protection programs against 

 forest pests have been undertaken in past years. 

 For the most part these have been only partially 

 successful, presumably because not enough has 

 been known about how to deal with these pests. 

 More effective research and action programs 

 could have the effect of materially increasing 

 future wood supplies. 



Timber yields could be enhanced, for example, 

 through control of dwarf mistletoe, bark beetles, 

 larch case bearer, and other insects and diseases 

 through development and use of attractants, 

 repellants, feeding deterrents, hormones, sterilants, 

 and parasites, as well as use of pesticides and im- 

 proved cultural measures. 



Protection against fire. — The largest and most 

 effective forestry effort in the United States, as 

 pointed out in Chapter II, has been in the control 

 of forest fires. The results have been remarkable, 

 with a decline in area burned from 30 to 40 

 million acres annually at the beginning of the 

 century to about 5 million acres annually, in the 

 late 1960's. 



