B.S.F. or B.Sc.F. Bachelor of Science in Forestry Forest Mensuration and Timber Inventory 2 — Questions and Answers
Question 1: The USDA Forest Inventory and Analysis (FIA) program provides:
- Timber sale contracts for National Forests
- A national database of forest area, volume, growth, and mortality updated on continuous cycles (Correct answer)
- Grant funding for reforestation projects
- Wildlife population estimates for listed species
Correct answer: A national database of forest area, volume, growth, and mortality updated on continuous cycles
FIA is the nation's continuous forest census, remeasuring permanent plots across all ownerships to track changes in forest resources over time.
Question 2: Increment borers are used in mensuration to:
- Test soil compaction at the root zone
- Extract a core from a living tree to determine age and radial growth rates (Correct answer)
- Measure stem taper along the bole
- Sample sapwood for moisture content
Correct answer: Extract a core from a living tree to determine age and radial growth rates
An increment borer extracts a pencil-thin wood core from a standing tree, allowing foresters to count annual rings and measure past radial growth.
Question 3: What is 'stand volume' as used in timber inventory?
- The height of the dominant trees per acre
- The total wood volume of all trees in a defined area, usually expressed per acre (Correct answer)
- The number of trees per unit area
- The volume of individual logs after bucking
Correct answer: The total wood volume of all trees in a defined area, usually expressed per acre
Stand volume aggregates the estimated wood volume of all individual trees within a given area, typically reported in board feet or cubic feet per acre.
Question 4: The 'form factor' of a tree in mensuration corrects for the fact that:
- Trees lean away from vertical
- Tree stems taper and are not perfect cylinders, so actual volume is less than a cylinder of the same DBH and height (Correct answer)
- Tree crowns add mass not captured by DBH
- Bark thickness varies by species
Correct answer: Tree stems taper and are not perfect cylinders, so actual volume is less than a cylinder of the same DBH and height
The form factor (or form quotient) adjusts the theoretical cylinder volume (based on DBH and height) to the actual stem volume by accounting for taper.
Question 5: In a fixed-radius plot design, what information is primarily collected from each plot?
- Tree canopy cover estimates only
- Species, DBH, and height of all trees within the plot boundary (Correct answer)
- Root biomass of dominant trees
- Soil texture and organic matter content
Correct answer: Species, DBH, and height of all trees within the plot boundary
Fixed-radius plots record species identity, DBH, and often height for all qualifying trees within a set distance from the plot center, enabling volume and density calculations.
Question 6: Which of the following best defines 'cubic foot' volume as used in US forest mensuration?
- Volume of a log scaled by the Doyle rule
- The actual wood volume of a section of stem including bark (Correct answer)
- A 12 × 12 × 1 inch unit of sawn lumber
- Volume of a tree's crown projection
Correct answer: The actual wood volume of a section of stem including bark
Cubic foot volume is a measure of the actual wood (and sometimes bark) volume of a stem section, calculated from diameter measurements and section length.
B.S.F. or B.Sc.F. Bachelor of Science in Forestry Forest Mensuration and Timber Inventory 2
The USDA Forest Inventory and Analysis (FIA) program provides: