Teaching Forest Stand Dynamics

This presentation provides an overview of a field-based practical exercise that allows students in forestry, ecology and natural resources to develop their understanding of forest stand dynamics. The exercise involves measurement of key tree growth parameters in four even-aged, single-species plantation stands of different age but occupying sites with similar soil and environmental characteristics. The selected stands represent key stages in stand development, from establishment to rotation age for fibre production. In the field, students work in small teams to gather data from an equal number of plots within each stand. Tree parameters include top height, crown diameter, live crown ratio and diameter at breast height. In addition, information on stand density and understorey vegetation is collected. Plot size and number can be varied to suit the constraints of class size and available time, though circular plots of 100 m2 are recommended. In the classroom, data are pooled and analysis focuses on presenting tree and vegetation changes through time. The simplest way of interpreting the data is to prepare graphs and charts for each of the parameters, though more advanced statistical interpretations are possible. The project as outlined here can be modified to meet the needs of different groups, and has been successfully used in undergraduate teaching of silviculture and forest ecology, as well as in postgraduate courses in natural resources management.

Download Paper at URL: http://www.researchgate.net/publication/254307252_The_development_of_even-aged_plantation_forests_an_exercise_in_forest_stand_dynamics

1. Professional Forestry Education
Fundamentals of Forest Stand Dynamics:
An approach to experiential learning for forestry students
Edward Wilson
Silviculturist
Scottish School of Forestry
Inverness College UHI, Inverness, Scotland
18 July 2014
First presented: 18 07 2014
This version: v1.1, 18 07 2014RESEARCH
INTERNATIONAL

2. Outline
•Definition and relevance of Forest Stand Dynamics to forestry
education
•Organisation and approach to a learning session/activity
–Experiential
–Integrative
–Active
•Learning outcomes from completion of the session
•Questions and Discussion

3. Forest Stand Dynamics (1)
•What is Forest Stand Dynamics?
–The study of change in forest stand structure with time, including stand
behaviour during and after disturbance (human-caused or natural)
–Oliver and Larson 1996
•What are the Foundations of the Discipline of Forest Stand Dynamics?
–Observation
–Ecology, physiology, morphology, anatomy, environmental factors
–Facilitates study of Interactions –i.e., tree-tree, species-species, tree-site
–Enables understanding of Stand Growth and Succession
•Where does Forest Stand Dynamics fit in the undergraduate forestry
curriculum?
–Forest science
–Silvicultural systems
–Woodland ecology
–(Re-enforces learning in Forest mensurationand thinning control, and other
modules)

4. Forest Stand Dynamics (2)
•Why is Forest Stand Dynamics important for foresters?
–Aids understanding of forest development and responses to natural disturbance
–Basis for understanding the interactions and responses to planned interventions
•Predicting productivity and future yield
•Predicting future structure and composition
•Controlling silvicultural costs
•Habitat and conservation values
•Enhancing landscape-scale values
–Forests are complex systems and need to be managed to be both resilient (to
minimise effects of climate change, pests and diseases) and sustainable (social,
economic, ecological and environmental factors)
–Principles of forest stand dynamics apply to all forest types and forest biomes.

5. Development stages in a natural forest
initial stage intermediate stage final stage
Strategies for Enhancing Forest Resilience
Modify thinning regimes Extended “rotations”
Diversify stand structures
(i.e., CCF)
Species choice
-genetics/provenance
Mixed species
Assisted migration of native species
New species introduced
Wider use of “minor” species
Diagram based on Oliver and Larsen 1996
Adapted from graphic by Jens Haufe
open
ground
1. Stand initiation2. Stem exclusion3. Understoreyre-initiation4. Old growth
Intervention Options linked to Enhanced Resilience
Modify harvesting systems

6. Facilitating Learning in Forest Stand Dynamics
•Exercise designed to demonstrate
theory through an experiential learning
model
•Wilson and Leslie 2008 Journal of
Biological Education42(4): 170-176
•Selected for the Routledgespecial
collection of 100 scientific papers to
celebrate the UN International Year of
Forests, 2011
•Successfully applied and tested with
First Year HE forestry learner groups
•Learning activity in 2 parts (each 3
hours):
–Part 1–Field (Site inspection and data
collection)
–Part 2-data collation, presentation,
analysis and interpretation

7. Session 1: Site inspection and data collection
(Field Based) (3 hours)
Identify 4 stands in close proximity but at different stand ages
Greystoke Forest, near Penrith, Cumbria

8. Stand 1 Stand 2 Stand 3 Stand 4
Stand location (OS Grid Ref.)NY 387 346 NY 388 345 NY 393 340 NY 389 342
Stand age (years) 3 12 30 45
Altitude (m) 260 260 255 265
Aspect NE NE NE NE
Topography Gentle slope Gentle slope Lower slope Upper slope
Soil type Acid brown earthAcid brown earthAcid brown earthAcid brown earth
Soil texture Loamy clay Loamy clay Loamy clay Loamy clay
Rooting depth (cm) ~ 30 ~30 ~30 ~30
Wind hazard classification 4 4 3 4
Rotation Re-stocked Re-stocked Re-stocked First
Site preparation Mounded Mounded Ploughed Turf planted
Thinning Unthinned Unthinned
Row thinning
(1-in-6 rows)
at 20 yrs.
Low thinning
at 28 yrs.
Unthinned
Initial density (stems/ha) 2200 2200 2000 3700
Current density (stems/ha) 2200 2100 900 1800
Summary of stand characteristics

9. Basic measurements
•Health and Safety, Risk
Assessment completed and
explained
•PPE provided
•Learners work in small groups
•Each group visits each site/stand
•Complete measurements in
100m
2
or 200 m
2
plots (trees
and ground vegetation)
•Follow standard protocol and
submit data to session facilitator

10. Session 2: Analysis and Interpretation (3 hours)
•Introduction (10 mins)
–Outline the learning goals, objectives and structure of the session
–Review and reflect on key aspects of session 1
•FastFactsLecture (20 mins)
–Theory, terminology
•Explain the task (10 mins)
–Distribute handout and data sheets
–Explain steps required to complete the exercise
•Student Activity (in groups of 2-3) (90 mins)
–Summarise and collate data
–Present results in graphical format
–Create a stand profile diagram
•Review and reflect (30 mins)
–Group and class discussion
–Review of learning outcomes and reflect on application of knowledge to
forestry practice

11. Summary results(means)
Tree and Stand Parameters
Stand 1Stand 2 Stand 3Stand 4
Mean top height (m) 0.3 4.5 22.4 23.7
Mean live crown (%) 98 97 48 39
Mean DBH (cm) 0 7.1 23.2 22.0
Mean crown diameter (m) 0.3 2.0 2.8 2.2
Basal area (m
2
/ha) 0 8 38 68
GroundVegetation
(Relative Abundance –DominScale)
Stand 1Stand 2Stand 3Stand 4
1. Grasses 8 6 2 0
2. Woody plants 4 0 0 0
3. Non-woody plants
1
4 8 5 4
4. Needles/tree litter4 4 9 10
5. Bare soil 4 0 0 0
1
The dominant species in this group were mosses.

12. 0
20
40
60
80
100
0 10 20 30 40 50
Mean live crown (%)
0
5
10
15
20
25
0 10 20 30 40 50
Mean top height (m)
0
5
10
15
20
25
30
0 10 20 30 40 50
Stand Age (years)
Mean DBH (cm)
Grand
period
a.
b.
c. Presentation of Treeand Stand Relationships
1. Best-fit Line Graphs
a. Mean Top Height versus Stand Age
b. Mean Live Crown Ratio versus Stand Age
c. Mean DBH versus Stand Age

13. Presentation of Treeand Stand Relationships
2. Stand Profile Diagrams
Diagram can be annotated so that key features at each development stage are identified

14. Activities and learning outcomes associated with
completion of the exercise (1)
Activity Learning outcomes
Understanding silvicultural
relationships
Understanding the priorities in the allocation of
photosynthate
Relating the processes of self-thinning and
competition to even-aged stands
Recognising the stages in the development of even-
aged stands
Measurement of stand
parameters
Understanding fundamental tree parameters
Use of mensurationequipment
Basic maths (calculating heights from % and
distance, live crown percent)
Ecological survey methods (quadratsand measures
of abundance)
Identification of ground vegetation
Laying out plots Understanding of sampling
Calculation of areas

15. Activities and learning outcomes associated with
completion of the exercise (2)
Activity Learning outcomes
Recording field data Use of forms
Recording data legibly, neatly, accurately
Summarisation of data Use of calculators, spreadsheets
Understanding of basic statistics (mean values, but
more advanced analysis possible depending on the
group)
Preparation of graphs Use of chart function in spreadsheets
Understanding the labelling and other
requirements of graphs
Interpretation of graphsRelating field experience to quantitative data
Understanding of the influences of age and stocking
on stand and tree parameters
Describing the main resultsScientific writing skills
Referencing
Professional competenciesWorking in a team
Critical reasoning
Organising work

16. Professional Forestry Education
Reference
Wilson, E. R., and A. D. Leslie. 2008. The development of even-aged plantation
forests: a field-based practical exercise in forest stand dynamics. Journal of Biological
Education 42(4): 170-176
URL: http://silviculture.org.uk/publications/
Download: http://www.researchgate.net/profile/Edward_Wilson5
First presented: 18 07 2014
This version: v1.1, 18 07 2014
Contact Information
Edward Wilson
Email:[email protected]
Web:www.silviculture.org.ukRESEARCH
INTERNATIONAL