EVDEX OF HEADINGS 



707 



Logging and plant residues — Continued 

 Plant residues — Continued 



Plant residues in relation to input are greatest 

 in cooperage manufacture, least in preparing 



wood forpulping 



Use of plant residues 



Unused residues can help meet additional needs 



for timber products 



Trends in utilization 



Utilization in the woods 



Improved equipment and logging methods 



Expanding markets 



Shortages force better utilization of veneer 

 timber 



Page 



172 

 173 



175 

 176 

 177 

 177 

 177 



177 



Trends in utilization — Continued 



Utilization of plant residues 



The utilization outlook 



Conclusion 



The situation with respect to timber growth and 



utilization has improved 



Distribution of growth and cut are not well 



balanced 



Proportion of hardwood and of inferior species 



increasing 



Heavy reliance placed on small group of 



species 



Large opportunities for fuller and better use 



Forest Protection 



Page 



Introduction 185 



The basis for evaluating timber destruction 185 



Growth impact — the concept and definition. __ 185 



Interrelations of causal agencies 186 



Forest protection as analyzed in past national 



appraisals 186 



Tlie growth impact of forest damage occurring in 



1952 187 



Destructive natural agencies take heavy timber 



toU 187 



Mortality versus growth loss 189 



Status of protection from fire 189 



Fire protection in relation to the timber resource. 189 



Timber losses due to fire 190 



Total impact on growth is substantial 190 



Total growth loss exceeds mortality 191 



The current forest fire situation 192 



Man-caused fires still a problem 192 



Area burned in 1952 near current average 192 



Burned area mostly on private land 192 



A look at the status of fire control 194 



Major milestones in fire control 194 



Eighty-eight percent of lands now protected, _ 195 



Most unprotected land is privately owned 196 



Intensity of protection varies greatly 196 



Effective fire control expenditures unchanged 



in recent years 197 



Current trends toward better fire control 199 



Man-caused fires can be reduced 199 



Protected area being increased rapidly 201 



Intensification of fire control is big challenge. _ 201 



-Con. 



Status of protection from fire — Continued 

 Current trends toward better fire control- 

 Area burned is trending downward 



Status of protection from diseases 



Diseases reduce our timber supply 



Many kinds of disease cause major losses 



Advances being made in disease control 



Disease surveys, the first step toward control.. 

 Direct control necessary against some diseases. 

 Control through silviculture gaining ground — 



Status of protection from insects 



Insect impact on timber growth 



Important timber losses caused by many types 



of insects 



A new age in insect control 



Surveys are basic to detection and control 



Most major insects now combated by direct 



measures 



Biological control — a new tool against forest 



insects 



Insect control through silvicultural modifica- 

 tions 



Opportunities for salvaging insect-killed timber 



improving 



The impact of animal damage on timber growth.. 

 Many kinds of animals impede growth and 



regeneration 



Animal damage can be controlled 



Weather effects destructive to timber 



Catastrophic timber destruction since 1900 



The outlook for reducing timber losses 



Productivity of Recently Cut Lands 



Page 



Introduction 223 



Previous related appraisals 224 



Comparability of national surveys 225 



How concepts were developed 226 



Concepts and procedures 226 



Summary 226 



The elements adopted 228 



Page 



178 

 178 

 179 



179 



179 



179 



179 

 180 



Page 



202 

 203 

 205 

 206 



208 

 208 

 208 

 209 

 209 

 210 



210 



211 

 211 



212 



213 



213 



213 



214 



214 

 215 

 215 

 216 



218 



Page 



Concepts and procedures — Continued 

 The elements adopted — Continued 



Existing stocking 228 



Prospective stocking 229 



Species composition 229 



Effect of felling age or premature cutting 230 



Basic level of standards 232 



The productivity index and class 232 



L 



