Forest landscape management strategies for Alberta

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i i ihrarv BibHoth^que nationals
National , library panada

of Canada

CAN AD LANA

JAN 221991

Forest Landscape
Management
Strategies for Alberta

Liberia

FORESTRY,
LANDS ANDWILDLIFE
Forest Service

Pub. No. T/228
ISBN: 0-86499-756-6
(Revised 1990)
Original Printing 1986

FOR ADDITIONAL COPIES OF THESE GUIDELINES, CONTACT:

Information Centre
Forestry, Lands and Wildlife
Main Floor, Bramalea Building
9920 - 108 Street

Edmonton, Alberta, Canada T5K 2M4
Telephone: (403) 427-3590

n

Contents

Page

1. Introduction 3

1 . 1 Forest Landscape Management Ground Rules 5

2. Visual Resource Inventory 6

2.1 Visual Sensitivity Factors 6

2.1.1 Landscape Scene 6

2.1.2 Visual Perception 8

2.1.3 Social Sensitivity 11

2.2 Visual Sensitivity Rating 12

2.3 Inventory Procedures 13

3. Visual Quality Objectives 15

4. Visual Impact Assessment 17

4.1 Visual Absorption Capability 18

4.2 Assessment Techniques 20

5. Visual Management Actions 23

5 . 1 Design and Layout 24

5.1.1 Lineal Disturbances 25

5.1.2 Screening 27

5.1.3 Cutblock Shapes 30

5.1.4 Opening Size 33

5.1.5 Cutting Systems 34

5.1.6 Timing 36

5.2 Operations 38

5 . 3 Follow-up T reatments 4 1

5 .4 Effect of Time 46

6. Resource Management Decisions 47

Appendices 49

1. Physical Elements of a Viewshed 50

2. Visual Perception 53

3. Human Factors 54

Glossary 55

References 57

List of
Illustrations

Figure

1. Landscape Assessment Model

Page

5

2. Distance Zones

Q

L Angle of View

in

4. Landscape Sketch

20

ST Alternative Cutting Systems

71

6. Effects of Screening

7.7

Map

1. Land Classification Map

Page

7 )i

2. Landscape Inventory

14

List of Tables

Table Page

1. Visual Sensitivity Rating 13

2. Visual Quality Objectives 15

IV

Foreword

The Forest Landscape Management Strategies
are the result of an identified need to improve visual
quality of timber harvesting operations and other
industrial activities. The management of the visual
resources in areas of high public use and areas valued
for their scenic quality is of particular concern.

Many of the concepts and principles presented in
these guidelines have been adopted from those proven
by the U.S. Forest Service and the British Columbia
Ministry of Forests and Lands. Their programs have
greatly influenced the development and direction of
the Alberta Forest Service program.

The Forest Landscape Management Guidelines
seek to demonstrate the strategies that may be used for
the integration of landscape management with other
resource concerns. These guidelines shall play an
integral role in good forest resource management, and
will assist resource developers and managers in
identifying areas where forest landscapes have
aesthetic importance.

The interest and commitment for wise use of our
forest resources that is found in industry and
government agencies at every level within the
province has helped shape the program of Forest
Landscape Management in Alberta and will ensure its
success.

C. B. Smith
Deputy Minister

Alberta Forestry, Lands and Wildlife

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LAND CLASSIFICATION

GREEN AREA

PUBLIC LANDS
OPEN FOR SETTLEMENT

Forest Landscape
Management
Strategies for Alberta

Digitized by the Internet Archive
in 2016

https://archive.org/details/forestlandscapem00albe_0

1. Introduction

The landscapes of Alberta
present both constant and
ever-changing contrasts. The
open expanses of the prairie yield
to forested, rolling foothills,
and the dense canopy of the
northern forest; treed slopes
yield to the impressive barren
backdrop and enclosure of the
Rockies.

Scenic appeal is not limited
to natural features; cultivated
fields, for example, can contrib-
ute to landscape quality. Cul-
tured landscapes, influenced by
land use and structures, are
familiar to everyone.

People see landscapes in
different ways, and place
different values upon them.

The naturalist or wilderness
seeker finds enjoyment and
satisfaction in areas unchanged
by man. For the adventuresome,
the attraction of a feature is its
challenge; the mountain to the
climber or skier, the wild river to
the kayaker. For many, the
attraction of these same land-
scapes is increased when access
and facilities are provided.

Landscapes are constantly
changing, through both natural
events and human actions. The
viewers’ acceptance and under-
standing of landscape changes
are influenced by their memo-
ries and expectations for the
area, and their sense of how
well an alteration fits within the
landscape.

As recreational use of the forest
land is increasing, so is the
demand for extraction of resources
such as timber, oil, gas and
minerals. To underestimate the
potential visual impacts of these
activities can result in loss of
scenic values; to overestimate
them can lead to undue
restrictions.

3

The landscape is an element
which must be considered at all
stages of resource planning and
development in Alberta. To do
this, sensitive landscapes must
be identified, their quality rated
and their ability to withstand
change determined.

These guidelines will assist
resource planners and managers
in integrating, reconciling and
harmonizing forest resource use
within visually sensitive areas.

Planning for resource manage-
ment involves progressive
refinement of management
decisions, from the broad policy
level down to specific manage-
ment tasks. At each stage,
visual resource information must
be available at the appropriate
level of detail. With each
decision, future options become
less flexible.

Resource development in
Alberta takes place under
environmental regulations and
guidelines which benefit the
visual resource. Several hand-
books identify specific require-
ments for protection of aes-
thetic values. Among these are
The Resource Road Planning
Guidelines, The Resource Hand-
book, Timber Harvest Cutblock
Design, and Watershed Assess-
ment Manual.

Forestry operations are man-
aged in a manner that generally
protects landscape quality.
Smallwood utilization, winter
operations, slope operability
limits, mandatory reforestation
and thorough reclamation
requirements can minimize
adverse effects on the visual
environment.

The Forest Landscape Man-
agement Policy requires consider-
ation of visual resources.
Together with the Timber
Harvest Planning and Operat-
ing Ground Rules the policy
provides encouragement and
direction to Alberta Forest
Service and industry.

4

FIGURE 1

VRI

Visual Perception
&

Social Sensitivity

Inventory of Viewsheds

Landscape

Scene

VIA

U Visual Sensitivity Rating

*

Visual Quality Objectives

proposed alteration

Visual Absorption Capability

Visual Management Actions

Visual Management Recommendations

Other Resource
Recommendations

LANDSCAPE ASSESSMENT
MODEL

1 . 1 Forest Landscape
Management Ground
Rules

1 . The Forest Landscape Manage-
ment Policy shall apply in
visually sensitive areas.

2. The Forest Landscape Man-
agement Guidelines shall be
used to identify visual
resources, their sensitivity and
vulnerability, and to set
objectives for their manage-
ment, when in place.

3. In visually sensitive areas,
the guidelines shall be
applied to help determine
the visual impact potential of
proposed harvest operations.

4. In harvest operations with
significant potential for
visual impact, the guidelines
shall be applied during the
appropriate planning, opera-
tional, and post harvest
treatment phases to help
avoid or mitigate adverse
visual impact inconsistent
with visual management objec-
tives and good forest manage-
ment practices.

Visual resource management
begins with the assessment of
landscapes, using suitable
standards and techniques as
defined by these guidelines.

For areas where forest land-
scapes have aesthetic importance,
assessments can be conducted in
varying degrees of detail, from
broad inventory (Chapter 2) to
detailed assessment (Chapter 4).
The Forest Landscape Guide-
lines describe these methods
and the factors which must be
considered in making landscape
management recommendations.

5

2. Visual Resource
Inventory

The objective of landscape
assessment is to record the visual
landscape and identify the
factors which contribute to its
scenic value and significance.

The visual resource inventory
(VRI) is a quick and simple
process of recording the expanses
of viewable area on topographic
maps, noting the key features,
their prominence and sensitivity
in the view.

The inventory may be broad,
as for an entire travel corridor or
viewshed, or may be tailored to
a specific landscape unit which is
to be assessed.

Inventory should be done in
advance of resource develop-
ment decisions, so that compara-
tive landscape values can be
assessed and management
strategies worked out before
commitments are made.

In order to conduct the
inventory, one must have an
understanding of the factors
that create visual sensitivity in a
landscape.

2.1 Visual Sensitivity
Factors

Visual sensitivity is a measure
of the prominance and impor-
tance of a landscape.

Sensitivity Factors fall into
three categories:

1. Landscape scene characteristics.

2. Visual perception conditions.

3. Social sensitivity.

In combination these form
the visual sensitivity.

East Slopes of Alberta

2.1.1 Landscape Scene

The landscape scene is the
viewable area, also called the
viewshed, as it appears from one
or more viewpoints. A view-
point may be stationary or any
point in a corridor along which
the viewer travels (refer to

6

Altered landscape due to industrial activity.

Natural openings can create variety in
a landscape.

Appendix — Fixation and
Sequence Process).

Individual features may be
attractive in themselves, or
appear prominent because of
their position or arrangement.

Landscapes with a variety of
features are generally more
interesting and therefore visually
sensitive. As well, such land-
scapes are usually more able to
absorb modification by land
uses. This is an important
factor in visual impact assessment,
to be discussed under Chapter 4.

Each region of Alberta has
characteristic landscapes with
special qualities and appeal.
Assessment of the sensitivity of
a landscape takes into account its
location and surroundings. For
instance, a lakeside in the
north-eastern corner of the
province may not be as great an
attraction as a mountain lake in
the Rockies, yet its character,
uniqueness in its surroundings
and the interest of its users may
make it highly sensitive.

The scenic quality of land-
scape is influenced by its existing
condition. Nature continually
alters the landscape. As well,
human activities change the
landscape through resource use,
settlements and industry, recre-
ation opportunities and transpor-
tation. Alterations may include
new or improved access and
increasing the number of users,
thus raising sensitivity.

The arrangement of landscape
elements can add emphasis by
creating focus, panoramas or
confinement (refer to Appendix
— Physical Elements).

Landscapes with variety in
land form, rock form, water
form or vegetation can add
interest. However, a landscape
that is too complex may be less
attractive and, in some instances,
may be seen as having
deteriorated in quality (e.g.,
excessive cutblock size).

7

I

Variable or ephemeral condi-
tions can greatly affect land-
scape perception. These include
light, weather and movement.

Weather conditions such as
rain, wind, lightning, snow, fog
and temperature: all affect land-
scape quality and appreciation.

Each temporary condition
such as wetness, dryness,
running water, frozen ground
and snow accumulation has an
influence on the appearance of
the landscape, its colours,
reflections and contrasts.

Sounds of rushing water, wind
in the trees, wildlife, machines,
industry, traffic and people can
strongly influence the visitor’s
experience.

2.1.2 Visual Perception

Visual sensitivity is affected
by the limits of visual perception;
that is, the physical and mental
interpretation of how much the
eye can see. Easily measured
factors which relate to perception
are the distance between the
viewer and the feature, the angle
of view, intersection with the
landscape, and blockage of view
created by visual screening.

Ephemeral Conditions
(M ist / Haze / Fog )

8

FIGURE 2

Background

Middleground

Foreground

Distance Zones

1. Foreground — usually consid-
ered to be the first few
hundred metres of view,
sometimes up to about 1 km.
Fine detail is apparent, the
viewer is in the scene and can
feel a size relationship with
its elements. Perception of
colour is greatest; other
sensory experiences (sound,
touch, smell) are the most
acute. Wind motion is seen.

2. Middle Ground — ranging
from 1 km to about 8 km.
Overall shapes and patterns
begin to emerge, individual
trees are now seen as
stands, and the relationship
between landscape units can
be discerned. Variations of
light and atmospheric qual-
ity can either soften or
exaggerate colour contrasts.
The middle ground zone is
often the most difficult to
work with .

3. Background — from about
8 km to infinity. The scene is
strongly influenced by atmo-
spheric quality, little texture
or detail is apparent, and
entire landscape units are
seen. As distance increases,
individual impacts are less
apparent.

SOURCE: USFS, Forest Land-
scape Management

9

FIGURE 3

Angle of View

The position of the viewer in
relation to the angle of the slope
influences perception. How
much viewers can see, and their
perception of it, depends largely
on this position. From an
elevated viewpoint, much can be
seen. “Maximum opportunities
are present for distance views or
panoramas, visual blockage is
least restrictive” (USFS, Forest
Landscape Management). At a
lesser angle in relation to the
land plane, perspective foreshort-
ening reduces the scale of what is
seen. The same effect occurs as
the alteration moves away from
view horizontally (refer to
Appendix — Observer Position).

Screening of View

Viewer perception can be
limited by buffers or screens.
Attention can be indirectly
focused to certain points or views
in a landscape (refer to
Screening — page 27).

10

2.1.3 Social Sensitivity

The social component of
viewer sensitivity for an area is
a combination of a number of
factors:

• the number of visitors or
users;

• their length of stay;

• their level of concern for
scenic quality;

• their knowledge of an area.

Communication with local
user groups can help define the
level of concern (refer to Appen-
dix — Evaluating Landscapes).

11

2.2 Visual Sensitivity
Rating

The scenic quality features,
perceptual and social factors
which have been discussed
combine to produce the visual
sensitivity of a landscape (refer
to Appendix — Human Factors).

A three-class rating system
separates distinct landscape
units and provides some direc-
tion on the degree of caution
required in developing land uses.
The classes are broad and their
limits are not rigidly defined,
therefore they will overlap or
merge during landscape assess-
ment.

The ratings serve as “red
flags” to identify visual resources
for which further consideration
is needed.

Features in the landscape may
be unique or special for their
own character, or may attract
attention because of their
position. For example, focal
slopes in the line of sight are
seen by viewers driving a
highway; features adjacent to
sites where people spend time
(recreation sites, rest stops,
lakeshores) are highly rated.
Other attractions include varia-
tions in topographic relief and
features of dominant scale:
broad views, Rocky Mountain
massifs, lakes.

VISUAL SENSITIVITY
RATINGS

High Quality Landscape —
High Sensitivity

Quality Landscape,

Medium Sensitivity, Common to Area

Low Concern — Low Sensitivity

12

2.3 Inventory Procedures

The method of conducting an
inventory of visual resources is
set out in the following steps.

1 . Select the corridor, viewshed
or landscape unit of interest.

2. Obtain aerial photographs and
topographic maps to cover
the expected extent of the
viewshed. The NTS 1:50 000
topographic maps provide ac-
ceptable detail for orientation.
1:15 000 maps may be used
for small units.

3. Map the boundary of the
viewable area, as seen from
vantage points and along
entire travel corridors. Non-
visible areas within the
boundary are to be deline-
ated and marked nv.

4. Indicate key features with
arrows. Key features include
dominant large landscapes,
focal small landscapes and
features that are unique or
likely to attract attention.

5 . Rate the visual sensitivity of
the landscape, within the
mapped viewable area boun-
dary. This requires some
judgment and “feel” for the
entire area and its component
parts, the landscape units. A
unit can be large or small, but
is distinguishable from its
neighbors by characteristics in
any of the three categories
that create visual sensitivity.

6. Obtain photographs from
key viewpoints. Panoramas
can be recorded with
overlapping shots.

TABLE 1

Visual Sensitivity Ratings

HIGH

— Directly seen in near view
— Dominant in more distant view
— High quality landscape
— Unique or high feature interest
— Viewers stay long, have high concern, are
many in number

MEDIUM

— In clear view or close
— Less interest or dominance than high
— Viewing opportunity creates less concern
— Quality landscape, but common to area

LOW

— Viewed from distance low prominance in the
view

— Low concern

— Viewed obliquely and/or briefly while
travelling

— Low quality or monotonous landscape

7. Make written comments on
the key features, the viewing
opportunity and the existing
visual condition of each
major unit. If improve-
ments in access are planned,
the expected increased use
and effect on visual sensitiv-
ity must be taken into
account.

8. Provide the inventory map to
resource planners and manag-
ers to help guide the allocation
and structure of resource
development in key sensitive
areas (page 14). Landscape
sensitivity rating provides a
flagging of the more critical
areas. It also reveals areas not
in need of visual manage-
ment considerations.

13

MAP 2

VISUAL RESOURCE INVENTORY MAP

LANDSCAPE INVENTORY

TWO LAKES ROAD CORRIDOR
GRANDE PRAIRIE FOREST
SCALE 1 : 50 000

THE VISiBLE LANDSCAPE BOUNDARY

LANDSCAPE FEATURES

View of Dominant, Large Landscape
View of Focal, Small Landscape
Non-Visible
Viewpoint

landscap: sensitivity

pg Hi«"

L M...J Medium

( L Low

N. V.

o

3. Visual Quality
Objectives

On completion of the visual
resource inventory, broad objec-
tives for visual resource manage-
ment can be established. To
aid in integrated resource
planning these objectives, known
as VQOs, set limits to the form
and scale of visible alteration
considered acceptable to the
average visitor. In general, the
greater the visual sensitivity,
the more restrictive should be
the Visual Quality Objective.

Visual Quality Objectives may
also have an influence on
resource availability and the rate
and sequence of utilization. The
actual effect of a particular VQO
on resource development, if
any, is determined through
visual impact assessment
(Chapter 4).

Two additional objectives are
designed to either establish or
re-establish the desired level of
visual quality (enhancement and
rehabilitation).

The final VQOs, which are
adopted after other resource
needs and constraints are taken
into consideration, may differ
from the recommended VQOs.

TABLE 2

VISUAL QUALITY OBJECTIVES

P preservation

No activity, allow for ecological
changes only. Applied in
special management areas,
zones or, on a smaller scale, to
high value feature landscapes
such as shoreline recreation
sites and buffers, etc.

Management implication may
range from long-term retention
to full protection.

R retention

Activities not visually evident,
repeat form, line, colour and
texture found in the

characteristic landscape.
Change in size, amount,
intensity, and direction should
not be evident.

PR partial retention

Slightly altered, activity natural
appearing and subordinate to
the characteristic landscape,
though it may introduce

contrast.

M modification

Activity may visually dominate,
but borrows from the forms,
lines, colour, or texture of the
characteristic landscape such
that its visual characteristics are
of natural occurrences within
the surrounding area or character
type.

MM maximum modification Activity may dominate the

characteristic landscape, may
be out of scale or contain detail
which is incongruent with
natural occurrences, but is
viewed as natural when in the
background.

SOURCE: USFS, National Forest Management, Vol. 2
Two short-term management goals may also be determined.

ENH enhancement

Improvement of existing visual
conditions.

REH rehabilitation*

Directed at site recovery.

*The visual condition of altered landscapes can be tracked over specified
time periods (e.g., one year, five years, 20 years). The acceptable period
; to meet a given VQO will vary but must appear reasonable, i.e. , the

more restrictive the VQO the shorter would be the recommended

recovery period.

15

Preservation — High value, feature
landscape, no activity allowed.

Retention — Focal landscape,
activity should not be evident.

Partial Retention — Landscape
presently altered, activity is subordinate
and blends well.

Preservation might be prop-
erly defined as long-term
retention, because visual resource
values may not always persist
and other resources may take
priority at a later date.

The term Maximum Modifica-
tion does not mean that the
visual quality of a landscape
should be modified to the
maximum. It does indicate that
in some areas resource develop-
ment may dominate and
landscapes may be greatly
altered. This could apply in
areas where resource activities
are already dominant, or where
landscapes are common and
levels of concern are low. Visual
resource inputs to decision-
making will be relatively minor,
allowing increased attention to
more sensitive areas.

With the setting of a Visual
Quality Objective, the land-
scape assessment process for an
area may be terminated, or, as
projects are proposed, the Visual
Impact Assessment, Chapter 4
can be applied to specific
landscapes.

16

Modification — Activity dominates,
but borrows from the characteristics
of the landscape.

Maximum Modification — Activity
dominates, is out of scale — but
appears natural when viewed in
background.

4. Visual Impact
Assessment

When alterations to a visually
sensitive area are proposed, a
Visual Impact Assessment (VIA)
should be conducted.

The VIA estimates visual
impact potential, a measure of
the contrast caused by alteration
of the landscape. In doing this,
the most important factor to be
considered is Visual Absorption
Capability (VAC), the capacity of
the landscape to absorb alter-
ation without visual impairment.
The ability of the landscape to
recover over time is also a valid
and important factor.

17

4.1 Visual Absorption
Capability

Visual Absorption Capability
(VAC) is affected by the
interaction of three types
of factors:

1 . The character of the existing
landscape, its complexity of
form, line, colour and
texture;

2. Perceptual factors including
distance, angle of view
screening; and

3. Productivity of the site, which
indicates its potential to
recover and recovery rate.

An assessment of the visual
vulnerability of the landscape to
being altered will provide data
to help determine whether the
project is acceptable as proposed,
needs modification or should be
abandoned.

The expected degree of
contrast, determined by field
observation and office evaluations,
can be categorized as high,
moderate or low.

Reliability of the judgment
will be related to the quality of
information on the physical
resource and the social sensitivity,
as well as the experience and
preferences of those doing the
assessment, and consideration
for the groups they represent.
Bias and imbalance may be
avoided by using a representative
team.

Enhancement — Improvement of
existing visual conditions.

Rehabilitation — Recovery of site
over time.

18

HIGH VAC

— complexity of vegetation,
topography and surface
patterns, lines, colours,
textures — land use
modifications may already
be present in the view.

— modification will be subordi-
nate, low contrast

— low visual magnitude, land
surfaces are seen at acute
angles, vertically and/or
horizontally

— effective visual screening

— rapid recovery possible

LOW VAC

— uniformity of surface colour
and texture

— no existing alterations in
view

— high relief or visual magni-
tude, direct view

— little or no screening

— modification will be dominant
in the view or have high
contrast in form, line, colour,
texture

— slow recovery

19

4.2 Assessment Techniques

The most obvious way to
examine the proposed alteration
for its visual impact potential is
by direct observation.

If an inventory of the visual
resource has not yet been
conducted, it will be necessary:

• from key viewpoints, to assess
the scenic character, the
perceptual limitations, and
the viewing distance; and

• to determine the social
sensitivity of the site by
present use and types of
users.

Once the above data has been
collected, it will then be possible
to:

• assess the scale of the proposal
and the contrasts it will create
in form, line, texture, colour
and pattern with the existing
landscape;

• locate the proposed alteration in
the landscape by matching
landscape features such as rock
outcrops, meadows and timber
type changes on aerial photo-
graphs with the same features
in the view; and

• also note existing patterns of
alteration such as cutblocks
and seismic lines.

Sketching

The main forms and lines of
the landscape and some of the
variety, such as forest type
change and existing openings,
can be quickly recorded on
sketches. The proposed shape
and position of the alteration can
be estimated and drawn.

20

Kiosk — Pierre Greys Lakes —
Edson Forest

Photography

A photographic record of
existing visual conditions may be
compared with future condi-
tions to see if the visual quality
objective has been achieved. As
well, photographs show the
detail and arrangement of
components in the view and
allow the assessment process to
be continued back at the office.

Broad panoramas can be
recorded by taking a series of
overlapping photos. These can
be put together to display the
full breadth of the view.

As with sketches, photographs
provide a quick simulation of the
important elements of the
landscape and, through the use
of overlays, the expected
appearance of the alteration.

Photographic slide projections
are excellent means for display-
ing and using landscape
information. When the image is
projected on flip-chart paper,
the important elements can be
marked and the alteration
approximated. This process is
especially effective in the
development and testing of
design alternatives.

For more convincing simula-
tion, photos can be retouched.
Retouching may require the
services of an artist, particularly
when the photos are for public
presentation.

For timber operations, long-
term plans such as Timber
Management Plans and cruise
order maps are good sources of
information. Photo simulations
of the view, showing stages of
cutting over a period of years
and the effect of regrowth, or
“green-up” can be placed on an
information kiosk at the site.

21

Computer Simulations

Computer systems are now
available to translate planimetric
data from topographic maps
and planning maps into perspec-
tive views of the landscape and
planned alterations as they would
appear from given viewpoints.
One such program in use by the
Timber Management Branch is
called DTM, referring to the
Digital Terrain Model it creates
from normal topographic maps.

Computer simulation has
many advantages. It is not
affected by weather and travel
conditions, and areas can be
rapidly assessed from any
number of viewpoints. Study can
focus on either single projects
or on land use over a large area.

The visible portions of the
proposed activity and the
landscape itself are determined,
and the screening effect of
vegetation surrounding the
proposed alteration is indicated.

Drawings produced by DTM,
especially if enhanced with
colour, are convincing simulations.

The appearance of alternative
designs can be quickly assessed
by DTM. This capability is most
important in a design workshop
situation, particularly when
participants have the knowledge
and responsibility for technical
feasibility and field layout.

Planimetric detail such as
roads and cutblocks can be
superimposed on the resulting
perspective.

Maskuta Creek — Edson Forest

22

FIGURE 5

Aesthetic Layout

Alternate — Checkerboard Pattern

ACTION C

Progressive Clear-cut

Many, Small Blocks

5. Visual Management
Actions

The VIA process can also be
used to determine acceptable
design and layout, and to devise
measures to be taken upon
completion of operations to
reduce visual contrast.

The Visual Impact Assessment
for a project may show that its
appearance should be improved.
The next step is to select visual
management actions, which will
minimize or mitigate impacts.

Three areas are to be
considered:

1. Design and layout — line,
shape, pattern, size, timing,
cutting systems.

2. Operations — utilization, field
modification.

3. Follow-up treatment —
reclamation, scarification,
reforestation.

It is important to consider
the effect of time and the
productivity of the site on the
rate of visual recovery.

Viewing opportunity and
level of concern are factors to
consider in establishing an
acceptable recovery period.

23

5.1 Design and Layout

Project design must consider
all the elements of visual
absorption capability. The basic
elements of form, line, colour
and texture can be assessed and
the project manipulated to
achieve acceptable degrees of
contrast.

High contrast , poor blending and use
of basic elements.

Design conforms with basic elements in
the landscape.

24

Seismic Line/ Foothills Region

5.1.1 Lineal Disturbances

Line Contrasts

Seismic lines, transmission
lines and other lineal clearings
are conspicuous in uniform
coniferous stands. They can
create a notched effect in the
skyline.

Horizontal or diagonal align-
ment reduces visibility and
notching.

Attention of viewer is drawn by
vertical alignment.

Avoidance of Steep Slopes

The linear disturbance of
roads on side hills can be seen
for great distances if cuts and
fills are extensive. However,
timber operations in Alberta
generally avoid steep slopes, thus
reducing road work which
causes unfavourable visual impact.

25

Notched Skyline

Poor design, poor cleanup, unkept
appearance

Skylighting

The treatment of a skylit ridge
can have an important influence
on its visual absorption.

The notching effect of lineal
clearings, already mentioned,
occurs if the main orientation of
the clearing is along the line of
sight. Sensitivity is raised for
many years because the differ-
ence in tree height draws
attention even after a new stand
is established.

Individual trees left standing
in a skylit clearing can create an
unkept, wasteful appearance.

26

FIGURE 6

EFFECTS OF SCREENING

Partial forest cover, partial screen.

5.1.2 Screening

Visual buffers or screens are
beneficial in distancing, soften-
ing or eliminating the influence
of a land use activity. This raises
the landscape’s capacity to
support multiple uses.

Screening will affect how
much is seen in the view and
may consist of landforms,
vegetation or structures. Its
effectiveness varies with its
character (opacity or density)
and size (height and width). Its
influence is related to distance
and view angle and is especially
important in low viewing angles.
Objects in the foreground will
obscure large portions of the
view, but farther away the
effect diminishes.

Mature coniferous stands
may not provide effective visual
buffers at low viewing angles,
as their open understory may
allow a relatively clear view.

Clearing along a highway may
be beneficial, improving variety
and possibly opening views to
distant features.

Foreground vegetation fre-
quently forms the enclosure and
provides focal points for very
sensitive views, such as
lakeshores. Retention of such
key areas can also be of benefit
to wildlife, recreation and soils
management.

27

Foreground screening creating a
framed view.

Foreground screening.

28

Stream side buffers.

Roadside screening.

29

5.1.3 Cutblock Shapes

Cutblocks will have an
unnatural appearance if their
shapes contrast with existing
forms and lines in the landscape.

Blending can be achieved by
one or more of the following:

Offsetting Openings

Undulating Edges

30

Feathered edges — selective
removal of larger trees along the
edges of the block.

Using natural breaks in
topography — a measure which
can also improve the wind
firmness of the remaining stands.

31

Type Cuts

Stand types and density
strongly influence the pattern
and form of openings. Open
stands and areas with many
natural openings will have a
greater visual absorption
capability.

Cutting patterns are affected
by stand variability. Where fires
have created distinct age classes
and undulating forest type
boundaries, the best cutting
pattern both silviculturally and
visually will conform to those
boundaries. This layout also
reduces the threat of windthrow
in remnant stands.

Type Cut

Distinct age classes and species
diversity created through fire.

32

5.1.4 Opening Size

In considering the visual
impact of an alteration, size of
opening is often the most
important factor. The influence
of size varies with existing
conditions and variety of
topography in the landscape, as
well as viewing angle and
distance. Acceptable sizes range
widely, from the large scale of a
landform approach to the much
smaller than normal openings
permitted in a retention
landscape.

Opening size has a pro-
nounced effect on the overall
pattern of alteration in a view.
Large numbers of small
openings may create a mottled
effect, while the large openings
of a landform approach can
sometimes contribute to unity
in the landscape.

33

5.1.5 Cutting Systems

Two Pass System

A system for removal of
timber in two stages generally
works well but, in some
circumstances, depending on
visibility, slope, and rate of
growth, can be either too liberal
or too restrictive.

On large landforms in clear
view, a cut system with only two
passes may impose too many
openings at once, creating a
visual degradation.

Cutblock patterns can increase
the overall impact. To some
people a checkerboard pattern
may appear as well-managed
timber land, just as others
appreciate agricultural patterns.
On the other hand, in critical
areas the influence of a rigid
pattern can be quite severe.

Some flexibility in key areas
is necessary. Alternatives which
might be appropriate for
specific situations may include:

• block layout that is not rigid in
block size or pattern, but
conforms to the landscape.

• systems of three or more passes
for long-term retention of
stands in key positions.

• plans that retain flexibility for
change.

34

Alternative Cutting Systems

In areas of high sensitivity and
low VAC, such as the even-
textured coniferous stands of the
Eastern Slopes, alternatives to
clear cutting may be explored.

Selective cutting is a possible
alternative, but is a less suitable
system than clear cutting, in
relation to silvicultural require-
ments and stand re-establishment,

When planning harvests in
areas of high and medium
sensitivity, special attention
should be given to improved
design to balance the scale, shape
and pattern of cutting. Together
with early reforestation and
reclamation of roads, this
approach will soften impacts and
reduce the time they endure.

Unbalanced Scale , High Impact
From Roading

35

5.1.6 Timing

In many parts of Alberta,
winter logging is by necessity
rather than by preference.
Operations in the winter have
important environmental and
visual benefits. For example,
road building for winter
harvesting causes little distur-
bance of the soil surface, and
the roads are easily reclaimed or
recontoured when operations
have been completed.

36

37

5.2 Operations

At this stage, final design
alternatives can be selected to
improve the fit of the project in
the landscape.

Examples are:

Logging

• taking openings to a natural or
windfirm break;

• minimize the extent of skid
trails and roads, particularly in
steep areas.

38

Small wood utilization in
Alberta reduces the amount of
waste and debris from the
logging operation. Cleanup
requirements ensure clean
cutovers and landings.

The overall quality of the
operations, in respect to effect
on aesthetics, should be exam-
ined at this stage. Wasteful
practices, real or imagined, will
adversely affect public accep-
tance of a project.

Field modifications may be
introduced, if necessary, to
improve actual logging practices
which appear to be incompatible
with visual quality objectives
for the area.

Field Modification of Foreground
Blocks May Have Improved Visual
Quality.

39

Roads

• adjusting road locations includ-
ing the placing of doglegs to
break the line of sight into an
alteration.

Sharp Visual Contrast Caused by

Excessive Roading

• reduce or minimize the size and
amount of cut and fills on
steep terrain.

• remove debris and rehabilitate
exposed areas.

40

5.3 Follow-up Treatment

After logging, measures
taken to reduce contrast can
effectively improve landscape
quality and the public’s accep-
tance of a project.

41

Reclamation

Abandoned roads and landings
must be reclaimed to reduce the
chance of erosion and the
negative impact on open slopes.
However, within forest stands
right of way clearing remains
obvious. Seeding to grass
encourages quick visual ab-
sorption.

Before Reclamation

After Reclamation

42

Ripper Plow Scarification

Brush Rake Scarification

Scarification

Disturbance of the top layer
of soil is sometimes necessary to
assist and hasten artificial or
natural regeneration of logged
areas.

Some scarification methods
(brush rake, ripper plow) can
destroy established understory
vegetation and cause increased
contrast in the short term. This
loss of young trees and the
barren appearance of the logged
area are often the causes of
public concern.

43

u\

f w .» *“ 11 1

p

Jj v ||

t, III

Sjl

P

W'^yWiP?'.

f •. J&im%

Bracke Scarification

When other methods of
scarification are employed (disc
trencher, Bracke) damage to
existing vegetation can be
limited, avoiding negative impact
and public reaction. Scarifica-
tion can actually improve visual
acceptability by breaking down
and spreading unsightly accumu-
lations of slash.

Disc Trencher

44

Reforestation

Regrowth of vegetation softens
the contrast of land use
alterations.

Normal reforestation require-
ments ensure that cutover areas
will recover within a reasonable
time. Successful reforestation
must be achieved within 10 years
of logging. Debris and dis-
turbed soil generate a strong
colour contrast. Increased
growth of regeneration and
vegetation creates a more
pleasing effect to the eye, there-
fore, reforestation is a vital com-
ponent of landscape management.

In most operations, only 50%
of the merchantable timber is
removed at one time, and there
is a waiting period of about 20
years (or until the regeneration
reaches 2 m in height) before
the adjacent timber may be
logged. These rules provide
visual benefit by restricting the
overall rate of development and
encouragement of a green
landscape.

45

5.4 Effect of Time

The ability of a site to
recover over time has been
identified as an important factor
in visual absorption capability.
Contrasts in colour and texture
reduce over time until eventually
no change is evident.

Areas that are adequately
restocked may take many years
to be visually apparent, or
visually acceptable to the average
user.

The Acceptable Height of Regrowth
Will Vary With The Viewer.

46

6. Resource Management
Decisions

Resource decisions are based
on operational priorities in
relation to legislation, policies,
land use plans and zoning, and
guidelines for resource manage-
ment.

The relative values of each
resource, identified at the
inventory and referral stages,
guide those decisions.

Consideration of visual
resources should be a part of this
process.

These landscape guidelines
provide the methods by which
the visual resources can be
inventoried, their relative signifi-
cance determined and their
vulnerability to impairment
assessed. This information will
be included in comprehensive
resource management decision-
making.

Integration of Various Resource Uses

47

Fully informed decisions will

ensure that:

• High value landscapes will be
protected.

• Unnecessary visual impact will
be avoided.

• Unavoidable impact will be
reduced or mitigated.

• The capacity of the landscape
for multiple uses will be
increased.

• Public support and understand-
ing will be improved.

• Economic diversity and non-
economic benefits will be
enhanced by the mix of
resource extraction and ame-
nity values.

48

1. Physical Elements of
a Viewshed:

There are four elements that
compete for dominance in
landscapes. These are colour,
texture, line and form. They
are revealed to us through the
contrasts that their reflective
surfaces produce.

A) Colour:

Can be described by two
tonal qualities:

1) Hue — the reds, greens,
yellows, blues etc.

2) Value — quality of colour

— an object is either light
or dark.

There are exceptions,
but the following are
common contrasts in
colour value that can be
called rough rules:

i) sky — is invariably lighter
than earth elements

— clouds being infre-
quent exceptions

ii ) grasslands — are lighter
than tree or shrub cover

iii) soil — is likely to be
lighter than tree or shrub
cover, or only infre-
quently darker.

iv) disturbed soil — has a
distinct value contrast
compared to undisturbed
soil or plant cover.

v) hardwoods — are generally
lighter than conifers.

■urn

% ' 3

Overcast conditions or flat
lighting diminishes value con-
trasts; intense or full light and
seasonal changes increase value
contrasts.

50

B) Visual Texture:

• The way and the amount
of light an object reflects
depends upon the struc-
tural properties of its
surface.

• Light that strikes a rough,
jagged surface will be
scattered due to a variety of
angular surfaces.

• Light which strikes a
smooth, flat surface will
be reflected with a mini-
mum of scattering (e.g., a
lake broken with waves
compared with one that is
calm).

• Texture is lessened with
distance and atmospheric
conditions.

• Textures are most obvious
in side lighting and when
light intensity is strong,
casting distinct dark
shadows.

• Strong side lighting
increases the distance
within which textures
remain visible.

C) Line:

• The strength of line can
decrease with distance
due to atmospheric haze.

• Front lighting flattens
form and reduces line
strength so that often
only the skyline remains
evident.

• Side lighting accentuates
the silhouettes and edges
of separated forms.

• Back lighting blends
forms of equal distance
into one outline (e.g.,
mountain ranges).

D) Form:

• Shape and edge are terms
that describe form.

• These terms relate to how
they are silhouetted against
space.

• The form of an object is
its three-dimensional
character.

• Shape is the two-
dimensional impression
that the form of an object
may give.

• Sharp edge definition
produces high contrast
and a clear impression of
shape.

• Subtle edge definition
produces low contrast and
a sense of continuity
between the object and its
surroundings.

Four factors that relate directly
to, or affect the contrasts of the
elements are direction of light,
observer position, the fixation
process and how the observer is
exposed to the visual resource
(sequence).

1 . 1 Direction of Light:

There are three sources:

i) Back Lighting — when
facing the sun, makes
details of the landscape and
its surface become obscure.
Top outside edges are
emphasizes (early or late
day light).

ii) Side Lighting — produces
light and shadow patterns
which emphasize the
three-dimensional and tex-
tural characteristics of the
visual resource (mid-day).

iii) Front Lighting — when
the sun is to your back,
shadows are short, shade
falls away from the
observer and more surface
tends to be in full light.

• Form is accented by the
presence of shade and
shadow.

• North-facing slopes are
more likely to be
obscured by shade and
shadow than south
slopes.

• East or west slopes of
comparable gradient can
expect a similar amount
of sun or shade (but at
opposite times of the
day).

51

1.2 Observer Position

• Describes the elevation of the
observer relative to the object
that is viewed (can be below,
same or above) or observer
inferior, normal or superior.

i) Observer Inferior:

• below the surrounding or
nearby landscape

• usually when viewpoint is
in a valley or canyon
bottom

• in this position visual
blockage occurs most often
due to screening of plants,
trees and landforms

• greatest control over screen-
ing effects

• this position suggests direc-
tion of attention to
foreground detail, emphasis
of small parts and screen-
ing of segments.

ii) Observer Normal:

• position is present when a
level line of sight coincides
with the dominating
elements of the landscape.

• this position incorporates
characteristics of both
inferior and superior.

iii) Observer Superior:

• best description is a
mountain summit or ridge
top overview in which
maximum opportunities
are present for distant
views and panoramas.

• this position minimizes
visual blockage, is least
restrictive with respect to
limitations in enclosure,
screening, direction or
distance.

1.3 Fixation Process:

• Objects of the visual resources
are scanned by means of
exploratory movements. We may
move our bodies to gain a better
viewing location, our heads
relative to our bodies, or our
eyes relative to our heads.

• In scanning visible objectives our
eyes invariably come to rest, or
become fixed on the objects that
create the greatest contrast in
relation to adjacent objects.

• There is a hierarchy in how
objects “catch” our attention:

i) Moving objects — those in
the foreground dominating
those in the middle or
background.

ii) Figure objects — dominate
because of size, shape,
texture or tonal qualities.

iii) Subdued objects — subordi-
nate to figure objects due to
inferior size, shape, texture
and tone.

• This process is used to predict
what the public is most likely
to see when the way we look at
a visual resource is not entirely
voluntary.

1.4 Sequence

• The sequence or order in which
the visual resource is seen may
be random and free — as in the
case of the hiker who chooses
his own travel directions — or
it may be controlled and
limited as in the case of a train
traveller.

• In the controlled sequence,
the variety of seen objects is
limited strictly to those that
occur in the visual corridor of
the travel route.

• Actively plan for a variety-rich
sequence of visual experiences
when designing roads and
cutblocks. Layout should reduce
the adverse visual impact
associated with road building
and logging. The impact of
these activities frequently
depends upon people’s per-
ception, although the capability
of the landscape to absorb the
activity may play the larger role
in obtaining acceptance.

52

Natural Feature

Artificial Feature

2. Visual Perception:

• We respond to our environ-
ment through our senses — the
principal one of which is
vision.

• Seeing is uniform in all
individuals while perceiving
differs considerably from individ-
ual to individual.

— Individuals exposed to the
same scene from the same
place have the potential of
seeing the same objects but
they may or may not per-
ceive the objects similarly.

• Perceiving the visual resource
relates to how we react as
individuals to what we see. It
is the process of evaluating
what we do see in terms of
what we have seen and what we
expected to see.

• Seeing the visual resource
relates to the physical factors of
colour, form, line and texture
that stimulate our sense of
vision; each factor competing
for dominance.

• The process of awareness and
interpretation of what is seen
and experienced is influenced
by the physical factors and also
by human factors such as
emotion and intellect.

• We receive our impressions of
the world around us approxi-
mately as follows:

1.0% — taste
1.5% — touch
3.5% — smell
7.0% — hearing
87.0% — by sight

53

3. Human Factors

• We learn to form associations
with a great variety of the
objects we see.

• Classifications are made as to
which of them may be
considered dangerous or
harmless, beautiful or ugly,
valuable or worthless, unique
or commonplace, desirable or
undesirable, useful or useless
etc.

• How we classify what we see
depends on our individual
knowledge of the physical
world.

• How we interpret what we see
tends to be subjective:

A) What we have seen is
retained, both vaguely and
concisely, and is influ-
enced by our original
sensitivity to the parts of
the visual resource with
which we have come into
contact.

B) What we expect to see
depends upon what we are
led to believe and how
these beliefs and mental
images relate to what we
have seen. This may be
influenced by mental
images we form from
verbal and written informa-
tion about unseen objects
and places or the frag-
mented exposure through
visual media.

C) What we do see is compared
for recognition and evalua-
tion with what we have seen
and what we expected to
see.

Strange objects will be
mentally compared for
correlation with objects
that have generally similar
physical characteristics.

• Common Perceptions:

1) The process of visual
perception in which recall
and expectation influence
how we interpret objective
reality is common to all of
us. We all analyse the
visible world similarly.

2) Our responses to natural
objects are more predictable
than our responses to
artificial objects. We tend
to accept the products of
natural consequence more
readily than we do the
objects of artificial conse-
quence (e.g., earthquakes,
landslides, fire compared
with timber harvesting or
facility development).

3) The probability of visual
appeal is higher for land-
scapes rich in variety than
for landscapes that tend
toward monotony because of
their low object variety.
Variety produces more visual
stimulation.

4) Visual perception relies on
visual stimulation — you
must see objects in order to
applaud or criticize.

5) Visual perception may be
altered both positively or
negatively by exposure to
facts.

• We must learn to recognize
our own perceptual limitations
in managing the visual
resource. What may appeal to
our senses may not appeal to a
critical public.

Source: USFS Landscape

Management

54

Glossary

Aesthetic(s)

(a) Generally, the study,
science or philosophy
dealing with beauty and
with judgments concern-
ing beauty.

(b) Giving visual pleasure.

(c) The theory of perception or
of perceptibility.

Background

The distant part of a
landscape, picture, etc.;
surroundings, especially
those behind something and
providing harmony or
contrast; surrounding area or
surface. Area located 8 km
or greater from the viewer.

Basic Elements

Form, line, colour, and texture
are the visual recognition
parts which make up the
characteristic landscape.

Blending

Combining into an integrated
whole.

Characteristic

That which constitutes a
character; that which charac-
terizes; a distinguishing trait,
feature, or quality; a
peculiarity.

Characteristic Landscape

The naturally established
landscape within a scene or
scenes being viewed.

Contrast

Diversity of adjacent parts, as
in colour, tone, or emotions.

Design

A deliberate plan or scheme
to arrange elements so that a
desired pattern results.

Detailed Assessment

A relatively intensive reconnais-
sance of a landscape or parts of a
landscape.

Distinctive

Clearly marking a landscape or
landscape feature as different
from others.

Enhancement

A short-term management
alternative used to raise the
value, desirability or attractive-
ness of a landscape.

Focal

Drawing attention to a
central item of interest.

Foreground

The detailed landscape found
1 km or less from the
observer.

Forest Landscape

Landscapes in which the forest
is the most dominant
component.

Green-up

The process of re-establishment
of vegetation following
logging; usually herbaceous
growth and deciduous trees
appear first, followed by
conifers.

Landscape

Land form and land cover
forming a distinct pattern;
portion of land that the eye
can see in one glance.

Landscape Feature

A distinct or outstanding part,
quality or characteristic of a
landscape.

Landscape Inventory

A record of visible landscapes,
landscape features and an
estimate of landscape sen-
sitivity.

Landscape Management

The assessment, evaluation,
design and manipulation of a
landscape.

Landscape Sensitivity

Degree of landscape quality
based on physical and viewer
related factors.

Landscape Unit

An area indicating landscape
similarity.

55

Middleground

The space between the
foreground and the back-
ground in a picture or
landscape. The area located
from 1 km to 8 km from the
viewer.

Modification

A Visual Quality Objective
meaning human activity may
dominate the characteristic
landscape but must, at the
same time, use naturally
established form, line, colour
and texture. It should appear
as a natural occurrence when
viewed in foreground or
middleground.

Monotony

Complete repetition; tedious
sameness.

Panorama

An unobstructed or complete
view of a region in every
direction; hence a complete
and comprehensive view.

Perception

(a) People’s impression of an
object or space as based
on past and/or antici-
pated experiences.

(b) Making oneself aware of all
conditions and applicable
factors; comprehension.

Preservation

A Visual Quality Objective
that provides for ecological
change only.

Rehabilitation

A short-term management
alternative used to return
existing visual impacts in the
natural landscape to a desired
visual quality.

Repetition

Units identical in interest and
ability to attract attention, or
at least identical in some
characteristic.

Retention

A Visual Quality Objective
which in general means
human activities are not
evident to the casual
uninformed forest visitor.

Screening Effect

Hiding, restraining or
protecting.

Selective Logging

The partial removal of trees
within a forest.

Shape

Spatial form, often two-
dimensional.

Silvicultural Practices

Activities that relate to and
promote the rate and quality
of tree growth.

Variety

A mixture or succession of
different things, forms, or
qualities, creating diversity
within the visual environment.

View

A broad landscape or pan-
orama looked toward or kept
in sight; the act of looking
toward this object or scene.

Viewpoint

Location from whence a
landscape can be seen.

Viewshed

The visible area, as it appears
from one or more viewpoints.

Vista

A confined view, especially
one seen through a long
passage, as between rows of
houses or trees. A vista is
often toward, or focuses upon,
a specific feature in the
landscape. Unlike a view, the
vista is sometimes artificial
and is thereby subject to
design.

Visual

A mental image attained by
sight.

Visual Absorption Capability

(VAC)

The relative ability of a
landscape to accept manage-
ment manipulations without
significantly affecting its
visual character.

Visual Impact

An expression experienced by
what is seen.

Visual Quality Objective (VQO)
A desired level of excellence
based on physical and
sociological characteristics of
an area. Refers to degree of
acceptable alteration of the
characteristic landscape.

Visual Sensitivity

A measure of people’s
concern for landscapes.

56

List of References

Alberta. Energy and Natural Resources. 1984. A Policy for Resource
Management of the Eastern Slopes: Revised 1984. Edmonton. ENR No.
T/38.

1981. Internal Referral Systems of Alberta Energy and

Natural Resources. Edmonton. Inhouse Report. ENR No.

Dept. 10.

1985. Stream Crossing Guidelines — Operational Guidelines

for Industry. Edmonton. ENR No. T/80.

Alberta Forest Service. 1982. Resource Road Planning

Guidelines. Edmonton. ENR No. T/25.

1979. The Resource Handbook. Edmonton. ENR No. 75.

1977. Timber Harvest Cutblock Design. Edmonton. ENR

No. T/116.

Alberta Forest Service. Timber Management Branch. 1985.

Planning Process for Timber Harvesting. Edmonton. Unpubl. Rep.

Resource Evaluation and Planning Division. Resource

Planning Branch. 1983. A System for Integrated Resource Planning
in Alberta. Edmonton.

Crowe, Sylvia. 1978. The Landscapes of Forests and Woods. Forestry
Commission Booklet 44. London.

Fairhurst, Kenneth B. 1984. A Landscape Assessment of the Hidden
Creek Harvesting Proposal. Alberta Energy and Natural Resources.
Unpubl. Rep.

Hackett, Brian, n.d. Landscape Planning, an Introduction to Theory
and Practice, n.p.

Ivarson, Wayne D. n.d. Assessing Landscape Resources: a Proposed
Model. In Zube et al. Landscape Assessment pp. 274-288.

Province of British Columbia. Ministry of Forests. 1981. Forest Land-
scape Handbook. Victoria.

Smardon, Richard C. n.d. The Future of Wetlands: Assessment the
Visual-Cultural Values, n.p.

U.S. Department of Agriculture. Forest Services. 1973-1976. National
Forest Landscape Management, Vols. 1,2. Washington.

Yeomans, William C. 1983. Visual Resource Assessment — A User
Guide. Surveys and Mapping Branch. B.C. Ministry of Environment.

Zube, Ervin H., Robert O. Brush, Julius Gy. Fabos. Landscape
Assessment: Values, Perceptions, and Resources. Pennsylvania.

57