Principles of Analog Forestry

Analog Forestry is a silvicultural system
that seeks to create a tree-dominated
ecosystem that is analogous to the original
mature ecosystem in architectural
structure and ecological function.
Principles of Analog Forestry
Formula Database
Map

Structure Function
Design
Formula = Structure
Database = Function
Map = Design
Principles of Analog Forestry

The natural ecosystems of any area
represents the outcome of eons of
experience in dealing with the climate
and impacts at that place.
If the area or landscape in question is
fortunate enough to contain some
representative element, excellent! If
something remains, though in a
degraded condition, it is still useful,
there will be many lessons to be
learned.
If nothing remains, look to history,
books, stories, and local experience
build up an idea of what the land once
sustained. Observe the ecosystems
and the patterns of biodiversity in the
area to be treated.
Principle 1 Observe and record

Record the species and ecosystems present in the area under
treatment. The initial data will assist in setting a baseline against
which future observations their changes can be evaluated.
Recording is also of importance in evaluating the management
activity and in maintaining a management history.
It is important to record the physiognomic formula for the
vegetation types on the land. The structure of the system will
demonstrate a wide range of different architectural responses
varying from trees to lianas. While it is useful to appreciate that
there may be differences between juvenile and adult forms, the
primary design consideration will centre on the adult form. Thus
tree species are identified as having a terminal, decurrent or
excurrent growth structure, with the crown occupying a dominant,
co-dominant, intermediate or suppressed position. Other growth
forms are similarly recorded

1. Basic growth forms
Woody plants
Broadleaf evergreens
Broadleaf deciduous
No leaves
Semideciduous
Mixed
Herbaceous Plants
Grasses
Ferns
Lichens and mosses
2. Spe cial growth forms
Vines
Succulents (cactus)
Bushy plants/shrubs
Bamboos
Epiphytes
Palms
3. Le af Characte ristics
Consistency
Hard
Soft
Succulent
Size
Large (greater than 12.7 cm)
Medium (7.6-12.6 cm)
Small (2.5-7.5 cm)
Very small (less than 2.5 cm)
Symbol
E
D
O
S
M
G
F
L
V
S
U
B
Y
P
h
s
z
l
m
p
t
B. Structure
Height Cover
Height level Type of
Cover
8 = over 35 m Continuous
(over 75%) c
7 = 20-35 m Inte rrupted
(50-75%) i
6 = 10-20 m In patches
(25-50%) p
5 = 5-10 m Rare (6-
25%) r
4 = 2-5 m Sporadic
(1-6%) e
3 = 5-2 m Nearly
absent (<1%) a
2 = 10-50 cm
1 = less than 10 cm
EXAMPLES OF
FORMULA
Example 1
V7cdm, V6izn,
V6idm, V6rdg;
H2c, H2-6r, L2-7c;
S2-6c; E2-7i
P6i
Example 2
V8rdm, V7idm,
V6idg, V5rdg;
H2c; S2-6i;
L2-6c; T8c; E7-8h;
P7c;
S3h
**A good way to
become familiar wi th
the code is to draw
out the two examples
above and see what
kinds of forests are
being described.

Understand the ecosystem being
observed in as many perspectives
as possible. It will function in one
way for the ornithological element,
another for the herpetological
element another for the
hydrological performance and yet
another for its social and economic
performance. The ecosystem will
have certain physiognomic
features and taxonomic features.
A synthesis of many variables will
always yield better choices of the
species and patterns to be used in
design. This is when the
observations and records must be
synthesised with as much
scientific and traditional
information as possible.
Principle 2 Understand and Evaluate

The generation of a database
concentrating on the vegetation species
that are (were) present in the area and the
potential new species to be considered is a
critical part of such recording and should
be initiated at the inception of the project.
This enables an assessment of both
ecological function and anthropocentric
function, which includes economic, social
or cultural values provided by a single
species or by the community as a whole.
The performance of each member of the
vegetation complex impacts the stability of
the ecosystem. A soil building species
might contribute to its stability positively,
while an invasive species might contribute
negatively.

Once an understanding of the components of the ecosystem
in question is gained, it is possible to evaluate the species
within it in terms of the management goals.
Data Base exercise to determine species ecological functions and structures
Name Scientific Name Human Use Ecological
functions
Root
system
Growth form Micro-
habitat
Propagation
Manzana
tropical
Syzgium
malacense
Edible/
construction
Birds/insects Deep Overstory Tree shade Seed;
germination
15 dias
Platanillo Hiliconiaceae sp Floral Birds, reptiles Superficial Low growth humidity Seeds,
rhizomes
Durian Durio zibethinus Edible/
construction
Birds/
mammals
Deep Irregular Tree shade Seed,
grafting

The better a manager understands his or her land
the better will be the management response. A
good understanding of the geography of the land,
its peculiarities and its history is important prior to
design. A powerful tool, in understanding the land
is a carefully drawn out map that identifies the
most pertinent features of the farm. Mapping the
land is best done if developed as a series of
overlays. Once the physical boundaries have been
mapped, overlays that demarcate the contours, the
hedges, fence lines, vegetation, soils, wind
direction and water flow are some useful variables.
Know the land in terms of its soil condition and
biodiversity. The soil ecosystem and surface
vegetation are the most important assets of a farm.
The soil, as much as the trees, crops or livestock
upon it, is a constantly changing, living thing. All
we have to do is occasionally turn the soil with a
spade to be impressed by this fact. However,
something is very wrong with much of this resource
today. Salting, wind erosion, water erosion,
acidification and structural decline are on a
landscape scale, like scabs or wounds on a diseased
animal, these are indicators of ill health and
disease.
Principle 3 Know your land

The farm map or farm plan should reflect not only the
current situation but also the desired future condition.
Principle 3 Know your land

Identify the different economic outputs possible as a
consequence of the design. All of consumptive products
will have an optimum level of extraction. The
awareness of optimum yield level of each resource and
designing for sustainable production will assist in
setting the levels of yield and determining design.
Principle 4 Identify levels of yield
Design decisions as well as management
decisions, will ultimately be based on goals
and activities that facilitate the achievement
of such goals. A good knowledge of the
levels of yield both in terms of individual
species and ecosystem services is important.
The yield required will differ depending on
the priorities of the landowner or manager.
If the goal is conservation the yield will be
measured by increases in the target species,
if the goal is economic gain the yield will be measured in terms of
income or production. If the demand for yield is focussed on a
single crop the higher the yield required the more the production
system would move towards a single species monoculture.

Finally, the levels of yield should correspond to the value
set on different aspects of the design by the owner. For
instance one owner might look for Bird and Butterfly
increase as yield because ecotourism is seen as the income
source, while another operator might look for high value
market crop production because traditional agriculture is
seen as the income source.
Principle 4 Identify levels of yield

Every landscape has flow through it, solid, liquid, gas and genetic that
produce distinct patterns. Usually the direction of flow in solids,
liquids and gasses is governed by gravity, resulting in the very
characteristic drainage patters of water or soil flowing on land.
Similarly wind moving across the landscape produce some significant
patterns. Genes usually follow existing corridors of ecosystems
conducive for that species.
The understanding of the flow systems across the farm or land area to
be managed is useful in setting the design. Cutting across flow
systems is usually not productive. Following, augmenting or
ameliorating flow systems to improve the ecosystem being designed,
such that the crop or organism under management, will improve in
productivity.
The other consideration when looking at flow systems across a
landscape its the propensity to form reservoirs. In waterflow systems,
reservoirs, be it natural or artificial can contribute greatly to local
productivity. A similar relationship can be seen in the soil, with
mineral soils weathering and flowing to form reservoirs of
concentrate, the pattern is repeated in the flow of the organic fraction
of the soil.
Principle 5 Map out flow and reservoir
system (existing and potential)

Heterogeneity, or a difference between various
landscape elements is a fundamental cause of
species movements and material flows. The
distribution of species and the condition of
landscape structure are linked in a feedback loop
so that the expansion and contraction of species
among landscape elements has a major effect
on, as well as being controlled by, landscape
heterogeneity.
As spatial heterogeneity increases so does the
potential for energy flow across ecosystem
boundaries. As the number of individual
ecosystems increase within a landscape, a
greater proportion of edge animals and plants
move between adjacent systems. Thus, as
landscape heterogeneity increases so do the
flows of heat energy, nutrients and biomass
across the boundaries separating the various
elements.

Mineral nutrients flow in and out of a
landscape. Their residence time within
an ecosystem is governed by the
dynamics of wind, water and
organisms. Most ecosystems have well
developed regulatory mechanisms to
hold their requirement of nutrient
within that system. However
disturbance, especially when severe
disrupts these mechanisms and
facilitates transport to adjacent or
other ecosystems. Therefore the rate
of redistribution of mineral nutrients
among landscape elements increases
with the intensity of disturbance
within them.

Principle 6 Reduce ratio of
external energy in production
All ecosystems use energy to maintain their identity. In agricultural
ecosystems, productivity is a goal and energy is expended at
meeting this goal. Often energy subsidies from outside the farm have
to be provided. As an increase in the flow of energy tends to
organize and simplify the system, increases in external energy inputs
impact both biodiversity and sustainability. Increases of energy to
an ecosystem represent a measure by which ecosystem modification
can be addressed.
Increases in the input of energy to an ecosystem, tends to organize
and simplify that ecosystem and change its biodiversity, the removal
of that input will lead to a collapse of the system. The greater the
modification of the system, the greater it depends on external
inputs. Thus energy dependency can provide a measure by which
ecosystem modification can be addressed. In a heavily energy
dependent agricultural system, the natural or biological system has
been dispensed with and an artificial environment has been created
to allow for increased production. Such a system is not only
unsustainable; it creates a dependency cycle that the operator will
find difficult to break out of.

The example above illustrates the need to identify
baseline descriptors that can be considered as ground
states or thresholds from which a measure of
sustainability or non-sustainability can be described.
For instance, if a process uses a certain amount of
inputs to maintain its identity, it can be described
relative to that level of inputs identified as the baseline.
Any change in state that requires a change in the
amount of inputs required to maintain its stability and
productivity can then be evaluated as to its potential for
sustainability. If a process uses x inputs to maintain its
identity and if this process can maintain itself by
securing these from its environment, it can be termed a
sustainable process. Now the same process can be
accelerated or expanded by adding y inputs.

This process, while still maintaining its identity, has increased
in some manner but now requires a constant input of x+y to
maintain this state. The removal of the extra inputs could lead
to the process degrading to a state different to the original
ground state.

All farming land will be a part of a natural landscape. The boundaries
of which are often set by definition. A common criterion to delineate a
landscape is on a watershed basis. Once identified, each landscape
can be divided into various replicating, such as open fields, tree
covered, homesteads, roads, streams etc. A landscape will often have
many vegetation components ranging from mature native vegetation
to open meadows. The patches of remnant vegetation often being the
only habitat left for native biodiversity.
The connection of these habitat patches with corridors will reduce the
populations' vulnerability to extinction. Small isolated populations are
particularly threatened with extinction due to ongoing deterministic
factors and greater influence of stochastic processes Indeed it is the
stochasticity inherent in small populations (e.g. the chance that all
offspring born in one season are male) that will ultimately lead to its
extinction. Corridors can increase the effective size of the habitat
patch and lessen the chance of local extinction. The more analogous
to the original, the more effective the corridor. Another possibility is
to increase patch size by creating an outwardly expanding zone of
vegetation analogous to the original ecosystem
Principle 7 Be guided by landscape and
neighbours needs.

Principle 7 Be guided by landscape and
neighbours needs.

In the development of a forest system maturity brings changes in the
trophic web, which in turn, are demonstrated by changes in species
composition.
The tree species that are characteristic of each stage confer stability to that
particular stage, thus mid-seral successional stages are often better
adopted as design criteria for woodlots, orchards, home gardens, tree
farms or agroforests. Early successional stages are mimicked by annual
agriculture and pasture. Incorporation of ecological processes that
contribute to further stability, can thus lend a great deal to design. In the
tropics, the use of mid-seral leguminous trees such as Erythrina, Gliricidia,
and Inga as shade trees for tea, coffee and is common, as the crop plants
are shade adapted mid seral plants and do best in a microclimate created
by light shade.
Principle 8 Follow ecological succession

The early seral stages such as grasslands, herbfields, meadow etc.
have their particular seral analogues; these are the systems of
annual cropping or pasture. The ecological characteristics of the
early seral stages are r selected life strategies, that is plants that
are short lived, low root/shoot ratios, produce many seeds, etc.
While it is possible to enable many such ecosystems to develop
into more mature states, the relative advantages of changing this
land to forest type ecosystems has to be carefully considered.

In designing for structure, the seral stage that is best suited for
the crops chosen provides the model. Thus, if the crops in
question are annuals, such as cereal grain, beans, squashes etc.
the pioneer stages provide the model. If the crops in question
are perennials such as coffee, fruit etc, the later seral stages
provide the model. The pioneer stages in most ecosystems are
diverse and incorporate a range of plant types capable of high
productivity, a pattern often reflected in traditional agriculture.
The early seral stages of forest ecosystems, provide the next
growth or building up phase

Principle 9 Utilize ecological processes
Incorporation of ecological processes into design always contributes to
further stability. All ecosystems are driven by a series of processes
some of which are significant important and contribute to maintaining
stability and productivity. Ecological processes in every ecosystem,
allow for increases in efficiency through management.
The identification of key processes such as edge effects, where the
ecotone or the boundary between two ecosystems facilitates a higher
biodiversity, keystone species: A species on which the persistence of a
large number of other species on the ecosystem depends and whose
impacts are greater than would be expected from its relative abundance
or total biomass. or the use of indicator species, organisms that
correspond to a certain level or state of biodiversity, will enable the
design of an effective and elegant model.

Principle 10 Value Biodiversity
Biodiversity has been perceived in many ways over the
ages. It is pattern wrought in biomass at any time. It
provides the variety of our living world, has been the
source of human inspiration across cultures and ages.
Biodiversity provides the material as well as the
indicators for sustainable land management. In
modern times it is invaluable as a management tool as
the level of biodiversity is an extremely useful measure
of the health of ecosystems.
Thus, the integration of biodiversity needs into laws
and policies governing natural resource based
production systems is essential for management
towards a higher degree of stability and sustainability.

The pattern of increasing ecological stability with
increasing diversity in land use has been corroborated
by studies of traditional land managers, whose
management systems are sustainable and who
conserve a much higher level of biodiversity than
conventional responses . High levels of diversity in the
agricultural field produce positive effects of biological
control, spread the risk in marketing and production,
as well as distributing labour needs to fit with a single
family unit . These methods of land management have
much to contribute to biodiversity management.

Scientific approaches to the measurement of
biodiversity can yield methodologies that can
be used to set value on various types to land
management. However, it is also useful to
stop and reflect that humanity did not always
perceive biodiversity in such analytical ways.
Consider the sentiments of Chief Seattle in
1854.
Our ways are different to your ways. The sight of your cities
pains the eyes of the red man. But perhaps it is because the
red man is a savage and does not understand.
There is no quiet place in the white man's cities. No place to
hear the unfurling of leaves in the spring or the rustle of
insects wings. But perhaps it is because I am a savage and I
do not understand. The clatter only seems to insult the ears.
And what is there to life, if a man cannot hear the lonely cry
of the whip-poor-will or the arguments of the frogs around a
pond at night? I am a red man and do not understand. The
Indian prefers the soft sound of the wind darting over the
face of a pond, and the smell of the wind itself, cleansed by a
midday rain, or scented with the pinion pine.

However, Until modern society recognizes the fact that there are
values other than monetary, there will be a need for 'objective
measurement' to set value. To obtain some universally agreed
measurement of biodiversity is an important international goal.
Such an agreement can allow the linking of biodiversity
measures to development funding. An expressed objective of the
Global Biodiversity Strategy (GBS) is, 'to integrate biodiversity
conservation into international economic policy'
It is an issue today, because the beauty and wonder of the living
world cannot have meaning in the marketplace. As a
consequence, this value of biodiversity has retreated before the
onslaught of the monocultures of economic expediency.

ECOSYSTEMS
Páramo Amazonía
Manglares Galápagos

Maturity is the end condition all ecosystems
tend to develop towards. It represents the
ability to stay sustainable in a given
geographical site. Seral succession or the
gradual changing of species and structures in
an ecosystem as it moves towards maturity is a
singularly important consideration in design.
Maturity is a process more than an end
condition. Mature ecosystems are usually
higher in biomass, though not necessarily in
biodiversity than more immature systems. As
maturity confers stability every element of a
landscape that can mature should be
encouraged to do so. The term climax is often
used to denote the end state of seral
succession in tree-dominated ecosystems.
Principle 11 Respect Maturity

In the end, every artist has to use the palette at hand. The
database may be incomplete, the maps may be poor. Often, data
on the region may be lacking, familiarity with landscapes or
ecosystems are often superior to poor data. Every landscape and
its associated ecosystems will have unique characteristics, some a
level significant for design, others not.
Every landscape, every ecosystem has nestled within it many
more. Management and monitoring has to proceed on an uniform
scale. Responding to change on the landscape must be biased
towards system sustainability rather than short term responses.
All this requires the designer to respond skilfully and creatively
Principle 12 Respond creatively

Two approaches to drainage. One with efficiency of drainage as the dominant
design , the other with the natural system being the dominant design

Principles of Analog Forestry

More Related Content

What's hot (20)

Viewers also liked (10)

Similar to Principles of Analog Forestry (20)

Recently uploaded (20)

Principles of Analog Forestry