Units of measurement, symbols, significant digits and rounding off
1.1 Units of measurement and symbols
1.2 Significant digits
1.3 Rounding off
1.4 Bias, accuracy and precision
Individual Trees and Logs
2.1 Bole characteristics
2.1.1 Diameter
2.1.2 Height
2.1.3 Bark thickness
2.1.4 Volume
2.1.5 Stem form and taper
2.2 Log characteristics
2.2.1 Diameter
2.2.2 Length
2.2.3 Volume
2.2.4 Weight
2.2.5 Allowance for defect
2.3 Crown characteristics
2.3.1 Width
2.3.2 Depth
2.3.3 Surface area
2.3.4 Volume
2.3.5 Biomass
2.4 Stem analysis
Groups of Trees (Stands)
3.1 Number of trees
3.2 Diameter
3.3 Basal area
3.3.1 Fixed-area plots
3.3.2 Angle count sampling
3.3.3 Advantages and disadvantages of angle count sampling
3.4 Height
3.4.1 Mean height
3.4.2 Predominant height, top height, dominant height
3.4.3 Stand height curve
3.5 Volume
3.6 Crown closure
3.7 Crown biomass
3.8 Growth and increment
References
Appendix 1: Checklist of equipment and materials
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2.2.3 VOLUME
Logs differ in type and situation (long log or short log , butt log or upper log, barked or unbarked, single or stacked, representative point at butt end accessible or inaccessible, etc.) and these differences bear directly on the measurement procedures applied to derive their volume. A key factor underpinning the accuracy of the volume estimate of an individual log is awareness by the measurer of the error incurred by measuring at unrepresentative points. Log measurers should quickly appraise each log for aberrations in taper before measurement commences and adjust their measurement technique accordingly. For ease of reference, the various methods available for measuring logs are presented in Table 2.3 The legend for this table and the various formulas referred to within it are presented in Table 2.4.
Table 2.3 Procedures Appropriate for Deriving the Volume of Logs on the Ground
Table 2.4: Information Relevant to Table 2.3
The volume of individual pine logs (Pinus sp.) can be derived from log length (L) and diameter measured inside bark at both the small end (d) and large end (D) by applying the formula of Ellis (1982) derived for exotic pines in New Zealand, viz.:
This formula should apply reasonably well in Australia for two reasons: it requires input of inside bark measurements and the taper and solid shape of the central boles of New Zealand and Australian grown exotic pines are similar (the frusta approximate 2nd-degree paraboloids).