Wood Variation: Its Causes and Control

1 Wood Variation and Wood Properties.- 1.1 What Is Wood?.- 1.2 Kinds of Trees and the Wood Produced by Them.- 1.3 Important Wood Properties.- 1.4 Wood Specific Gravity (Wood Density).- 1.4.1 What Determines Wood Specific Gravity?.- 1.4.2 The Importance of Specific Gravity.- 1.5 Cell Length.- 1.6 Other Wood Characteristics.- 1.7 Cell Chemistry.- 1.8 Factors Controlling Wood Properties.- 1.8.1 The Change from Earlywood to Latewood.- 1.9 Different Woody Tissues.- 1.9.1 Reaction Wood.- 1.9.2 Juvenile Wood.- 1.10 Relationships Among Wood Properties.- 1.11 The Literature Related to Wood Variation.- 2 The Effect of Provenance Variation and Exotic Plantations on Wood Properties.- 2.1 The Effect of Differing Environments on Wood Properties.- 2.2 Provenance Variation in Wood from Natural Stands Within the Range of a Species.- 2.2.1 Examples of Provenance Variation in Wood Properties in Natural Stands.- 2.2.2 A Summary of Provenance Variability in Wood from Natural Stands.- 2.3 Wood Variation Related to Species and Provenance in Plantation-Grown Trees.- 2.3.1 Examples of the Effect of Provenance upon Wood Properties of Trees in Plantations.- 2.4 Wood Properties of Trees Grown as Exotics.- 2.4.1 General Considerations.- 2.4.2 Changes of Wood Properties in Exotics.- 2.4.3 Wood Properties of Exotic Conifers - General.- 2.4.3.1 The Tropical Pines - Pinus caribaea Example.- 2.4.3.2 Conifers from Temperate Regions.- 2.4.3.3 Summary - Wood Properties of Exotic Conifers.- 2.4.4 Wood Properties of Exotic Hardwoods.- 2.4.4.1 Exotic Hardwoods Other than Eucalyptus.- 2.4.4.2 Wood of Eucalyptus When Grown as an Exotic.- 3 Variation Within and Among Ttees.- 3.1 Introduction.- 3.2 Tree to Tree Variability.- 3.3 Variation of Wood Properties Within Trees.- 3.3.1 Wood Differences Within Annual Rings.- 3.3.2 Wood Variability at Different Locations Within a Tree.- 3.4 The Juvenile Wood Concept.- 3.4.1 Occurrence of Juvenile Wood.- 3.4.2 Juvenile Wood and Growth Rate.- 3.4.3 Importance of Juvenile Wood.- 3.4.4 The Properties of Juvenile Wood.- 3.4.5 Can the Amount of Juvenile Wood Be Changed?.- 3.4.6 Utilization of Juvenile Wood.- 3.4.7 Summary of Juvenile Wood.- 3.5 Variation from the Tree Center to the Bark.- 3.5.1 Radial Trends in Wood Properties of Conifers.- 3.5.1.1 The Hard Pines - Specific Gravity.- 3.5.1.2 Other Conifers - Specific Gravity.- 3.5.1.3 Radial Changes in Conifer Wood of Properties Other than Specific Gravity.- 3.5.2 Radial Trends in Hardwoods.- 3.5.2.1 Specific Gravity.- 3.5.2.2 Other Wood Characteristics.- 3.6 Variation from the Base to the Top of the Tree.- 3.6.1 Breast Height to Total Tree Correlations.- 3.7 The Effect of Total Tree Age on Wood.- 4 Wood Property Variation as Related to Tree Form and Reaction Wood.- 4.1 Introduction.- 4.2 Wood Properties Associated with Poor Tree Form.- 4.2.1 Solid Wood Products.- 4.2.2 Fiber Products.- 4.2.2.1 The Effect of Limbs Upon Fiber Products.- 4.3 Reaction Wood.- 4.3.1 Compression Wood - Conifers 143.- 4.3.1.1 Characteristics of Compression Wood.- 4.3.1.2 Effects of Compression Wood.- 4.3.2 Tension Wood - Hardwoods.- 4.3.2.1 Characteristics of Tension Wood.- 4.3.2.2 Effects of Tension Wood.- 4.4 Methods to Improve Tree Form.- 4.4.1 Better Forest Management.- 4.4.2 Use of the Proper Seed Source.- 4.4.3 Breeding for Branching Characteristics and Bole Straightness.- 4.4.3.1 Summary of Form Improvement Through Genetics and Silviculture.- 5 The Effect of Growth Rate on Wood Properties.- 5.1 Introduction.- 5.1.1 Patterns in Wood Production Resulting from Growth Rate Differences.- 5.1.1.1 Growth Rate - Wood Property Grouping of Forest Trees.- 5.1.2 Literature on Growth Rate and Wood Properties..- 5.2 Growth Rate and Wood Specific Gravity in Conifers.- 5.2.1 Growth Rate - Specific Gravity Relationship in the Hard Pines.- 5.2.1.1 Summary - Specific Gravity and Growth Relationships in Hard Pines.- 5.2.2 Growth Rate - Specific Gravity Relationships in Other Conifers.- 5.3 Growth Rate and Wood Specific Gravity in Hardwoods..- 5.3.1 Specific Gravity and Growth Rate in Ring-Porous Hardwoods.- 5.3.2 Specific Gravity and Growth Rate in Diffuse- Porous Hardwoods.- 5.4 Summary of Growth Rate Effects on Specific Gravity.- 5.5 Cell Characteristics and Growth Rate.- 5.5.1 Summary of the Relation of Cell Length to Growth Rate.- 5.6 Growth Rate and Aesthetic Qualities of Wood.- 5.7 Practical Application of Wood Changes Caused by Growth Rate Differences.- 6 Wood Properties Affected by Environmental, Biological, and Other External Agencies.- 6.1 Introduction.- 6.2 Effect of Site, Soil, and Climate on Wood Properties.- 6.2.1 Soil Properties and Wood.- 6.2.2 Summary - Effect of Site, Soil, and Climate on Wood Properties.- 6.3 Moisture Availability and Wood Properties.- 6.3.1 Moisture Effects on Wood - A Summary.- 6.4 Miscellaneous Biological Factors that Affect Wood Properties.- 6.4.1 Forest Pests and Wood.- 6.4.1.1 Disease and Wood Properties.- 6.4.1.2 The Influence of Insects on Wood.- 6.4.1.3 Effects of Other Pests on Wood Properties.- 6.4.2 Compass Direction in the Tree Stem.- 6.4.3 Temperature, Light, and Wood Production.- 6.4.4 Position of the Tree in the Stand.- 6.5 Unusual Causes for Wood Variability.- 6.6 Growth Stresses and Strains in Tree Stems.- 7 The Effect of Silvicultural Practices on Wood Properties.- 7.1 Introduction.- 7.2 Effect of Nutrient Differences and Fertilization on Wood.- 7.2.1 Fertilizing Conifers.- 7.2.2 Fertilizing Hardwoods.- 7.2.3 Wood Uniformity Following Fertilization.- 7.3 Tree Spacing and Wood Properties.- 7.3.1 Stocking Control by Thinning as Related to Wood Properties.- 7.3.2 Plantation Spacing and Wood Properties.- 7.4 Effect of Pruning on Wood.- 7.4.1 Direct Effect of Pruning on Wood Properties.- 7.4.2 Pruning to Improve Tree Form and Quality.- 7.4.3 Other Considerations About Pruning.- 7.5 Planting Techniques and Wood Properties.- 7.6 Resin Tapping, Resin Induction, and Wood Properties.- 7.7 Wood Properties of Coppice and Root Sprouts.- 8 Control of Wood Properties by Breeding.- 8.1 Genetics of Wood Properties.- 8.1.1 What Are Genetic Differences and How Are They Measured?.- 8.1.1.1 Types of Genetic Variation.- 8.1.1.2 What Kind of Tests Are Necessary to Determine Genetic Variation?.- 8.1.1.3 How Is Genetic Control Measured?.- 8.2 Genetic Control of Wood Specific Gravity.- 8.2.1 What Are the Components of Wood Specific Gravity?.- 8.2.2 Inheritance of Wood Specific Gravity in Conifers.- 8.2.2.1 Genetic Variation Among Provenances.- 8.2.2.2 Stand to Stand Variation in Specific Gravity.- 8.2.2.3 Tree to Tree Variation in Specific Gravity.- 8.2.3 Inheritance of Wood Specific Gravity in Hardwoods.- 8.3 Genetic Control of Wood Properties Other than Specific Gravity.- 8.3.1 Latewood Percent.- 8.3.2 Cell Length.- 8.3.3 Tracheid Diameter and Wall Thickness.- 8.3.4 Chemical Composition.- 8.3.5 Spiral Grain.- 8.3.6 Other Wood Properties.- 8.4 Interrelationships Among Traits.- 8.4.1 Genetic Relationships Between Specific Gravity and Growth Traits.- 8.4.2 Relationships Between Wood Specific Gravity and Its Components.- 8.4.3 Relationships Among Other Wood Properties.- 8.5 Controlling Wood Properties by Breeding.- 8.5.1 Breeding for Wood Specific Gravity.- 8.5.2 Breeding for Other Wood Properties.- 8.5.3 How Are Genetic Gains Obtained Operationally?.- 8.6 Summary.- 9 Future Importance of Knowing and Manipulating Wood Variability.- 9.1 General Concepts.- 9.2 The Need for Wood Improvement.- 9.2.1 A Specific Need - Uniformity.- 9.2.2 Possibilities and Trends for Changing Wood.- 9.3 Wood Properties Related to Product Quality - The Future.- 9.4 Nonconventional Wood Products.- 9.5 Summary.- References.- Species Index.