week 07 - upper canopy

Question 1

why sample forest vegetation?

Answer 1

obtain quantifiable information about the resource that allows reasonable decisions on its destiny, management, and use

Question 2

tree attributes

Answer 2

• age
  
  • temperate zone trees grow 1 ring / yr
  • total age: time since germination
  • BH Age: time since height exceeded 4.5’
  • Instrument: Increment Borer
• diameter
  
  • DBH is most frequently measured
  • US: inches @ 4.5’ ; world: cm @ 1.3m
  • on slope: measure from uphill side
• basal area: x-sectional area of tree @ BH, in ft²
  
  • ba (or g) is directly related to crown surface area
• height
  
  • total: tree base to top
  • height-to-crown: tree base to base of live crown
  • merchantable height: height to a min. top diameter
  • instruments:
    
    • hypsometers (anything measuring height):
    • height poles, clinometers + trig

Question 3

stand attributes

Answer 3

• age
  
  • total: avg of tree total age
  • BH age: avg of tree BH ages
  • plantation: elapsed time since planting, regardless of seedling age at that time
• dbh
  
  • mean dbh
  • Quadrate Mean DBH: dbh of the tree w/ the mean basal area
• height
  
  • average
  • dominant (defs vary)
    
    • just doms
    • doms & co-doms
    • predominant: avg of 100 tallest / ha
    • top height: avg of 100 largest diam
• site productivity
  
  • dominant height vs. age
  • James King site index curves
• TPA: trees per unit area
• Stand Basal Area: sum of ind. tree basal areas
• Species Composition: proportion of each species in stand

Question 4

crown classes

Answer 4

• D, dominant - crown extends over general canopy level
• C, co-dom - crown forms general canopy level
• I, intermediate - shorter that D/C, but still entends into canopy
• O, overtopped - crown entirely below general canopy level; no direct sunlight