Contents 



Page 



HIGHLIGHTS 1 



CHAPTER I. RECENT TRENDS IN FOREST LAND AND TIM- 

 BER RESOURCES 7 



Forest land areas 8 



Commercial timberland 8 



Other forest lands 9 



Trends in areas of commercial timberland 10 



Ownership of commercial timberlands 11 



Forest type groups 12 



Forest site productivity 13 



Timber stocking 14 



Stand-size classes 14 



Timber growth 15 



Recent trends in timber growth 15 



Net growth by ownership 17 



Net growth and potential growth per acre 17 



Impacts of destructive agents 18 



Volume of mortality 18 



Additional losses from destructive agents 19 



Salvage of mortality 19 



Timber removals 19 



Total timber removals 19 



Roundwood timber harvests 19 



Logging residues 21 



Other removals 24 



Net growth in relation to removals 25 



Softwood growth-removal balances 25 



Hardwood growth-removal balances 25 



Timber inventories 27 



Total timber volumes 27 



Softwood inventories 27 



Hardwood inventories 28 



Ownership of timber inventories 29 



Trends in timber inventories 29 



Plant residues 30 



Trends in utilization of plant byproducts 30 



Primary plant residues 31 



Secondary plant residues 33 



Bark residues 34 



CHAPTER II. PROJECTED TRENDS IN TIMBER SUPPLIES 



WITH 1970 LEVEL OF MANAGEMENT 35 



1970 level of forest management defined 36 



Forest fire control 36 



Insect and disease control 38 



Reforestation 39 



Timber stand improvement 41 



Fertilization 41 



Assistance to forest landowners 41 



Forestry research 41 



Other forestry measures 42 



IX 



