1. Forest Mensuration II Lectures 11 Stocking and Stand Density
Avery and Burkhart,
Chapter 15
Lecture 11
FORE 3218
Lecture 11

2. Definitions
Stand Density –is a quantitatively term describing the degree of stem crowding within a stocked area
Absolute or relative
Stocking –refers to the adequacy of a given stand density to meet some management objective
Understocked, fully stocked, or overstocked
Stand density and stocking are often applied interchangeably
A stand that is “overstocked” for one management objective could be “understocked” for another
Lecture 11
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3. Measures of Stand Density
Stand density – measures how thickly trees grow in a stand
Stems per unit area
Basal area
Volume
Indices
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4. Measures of Stand Density
Stems per unit area
Basal area
Relative stand density
Crown competition factor
Fully stocked
Subject stand
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5. Measures of Stand Density (cont.)
Stems per unit area
Basal area
Relative stand density
Crown competition factor
Fully stocked
Subject stand
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6. Measures of Stand Density (cont.)
Ontario’s Jack Pine DMD
(Archibald & Bowling OMNR NEST TN-005)
Zone of Imminent Competition Mortality
Zone of crown closure
RSD=1
=0.55
=0.15
Stems per unit area
Basal area
Relative stand density
Crown competition factor
RSD =
Density of the subject stand
Maximum density attainable with
the same as the subject stand
3/2 law of self thinning
Lecture 11
FORE 3218

7. Measures of Stand Density (cont.)
Stems per unit area
Basal area
Relative stand density
Crown competition factor
– reflects the area available to the average tree in a stand in relation to the maximum area it could use if it were open-grown
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8. Measures of Point Density
Quantify the competition level at a given point or a tree in a stand
Area overlap index
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9. Measures of Point Density
Distance-weighted size ratios
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10. Stocking
A ratio of comparison of the density of a subject stand to that of a “ideal” or reference stand
Volume
Basal area
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11. Measures of Stocking
What should constitute full stocking of a particular species on a given site?
Normal or fully stocked stand: in such a hypothetical stand, tree crowns are fitted together so that no sunlight is wasted and each crown is matched with a root system that fully utilizes the soil
Normal stands are “average best” -- closed canopy stands
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12. Stocking (cont.) Measures Mature stands Stands at regeneration stage
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13. Stocking Guides
Depicts the relationship between basal area, trees per ha, and quadratic diameter at breast-height 15 20 25 30 A B
Mean DBH (cm)
Basal area per ha 10
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Trees per ha