ArticlePDF Available

All about the ‘wow factor’? The relationships between aesthetics, restorative effect and perceived biodiversity in designed urban planting

Authors:

Abstract and Figures

Urban populations experience the multiple health and well-being benefits of nature predominantly via urban green infrastructure. If this is to be designed and managed optimally for both nature and people, there is an urgent need for greater understanding of the complex relationships between human aesthetic experience, well-being and actual or perceived biodiversity. This integrative study assessed human aesthetic reaction, restorative effect and perceived biodiversity in relation to fine-grained categories of woodland, shrub and herbaceous planting. We surveyed 1411 members of the public who walked through planting of varying structure, species character and percentage flower cover whilst completing a site-based questionnaire. Semi-structured, in-depth interviews were then carried out with 34 questionnaire participants. Correlations between perceived attractiveness and perceived biodiversity were identified for three out of four biodiversity indicators. There was a correlation between perceived attractiveness and restorative effect yet this was not strong. Colourful planting with flower cover above a critical threshold (27%) was associated with the highest level of aesthetic preference. Subtle green ‘background’ planting afforded a restorative effect. These results are discussed with reference to the Circumplex Model of Affect. Our findings indicate that people appreciate colourful flowering public planting for the ‘wow factor’, but that green planting outside the narrow flowering season of most species is greatly valued. Planting moderately or most natural in structure was perceived as significantly more restorative than that least natural in structure suggesting that people in the UK may be increasingly accepting of a messier ‘ecological aesthetic’ in urban planting.
Content may be subject to copyright.
Landscape
and
Urban
Planning
164
(2017)
109–123
Contents
lists
available
at
ScienceDirect
Landscape
and
Urban
Planning
j
our
na
l
ho
me
pa
g
e:
www.elsevier.com/locate/landurbplan
Research
Paper
All
about
the
‘wow
factor’?
The
relationships
between
aesthetics,
restorative
effect
and
perceived
biodiversity
in
designed
urban
planting
Helen
Hoyle,
James
Hitchmough,
Anna
Jorgensen
Department
of
Landscape,
University
of
Sheffield,
United
Kingdom
h
i
g
h
l
i
g
h
t
s
Strongest
correlation
between
perceived
attractiveness
and
perceived
insect
benefit.
Positive
correlation
between
perceived
attractiveness
and
restorative
effect.
Planting
with
flower
cover
27%
or
above
perceived
as
most
attractive.
Subtle
green
planting
afforded
greatest
restorative
effect.
Planting
with
moderate
or
most
natural
structure
most
restorative.
a
r
t
i
c
l
e
i
n
f
o
Article
history:
Received
24
March
2016
Received
in
revised
form
13
March
2017
Accepted
23
March
2017
Keywords:
Urban
green
infrastructure
Aesthetic
Perceived
biodiversity
Restorative
effect
Percentage
flower
cover
Circumplex
model
of
affect
a
b
s
t
r
a
c
t
Urban
populations
experience
the
multiple
health
and
well-being
benefits
of
nature
predominantly
via
urban
green
infrastructure.
If
this
is
to
be
designed
and
managed
optimally
for
both
nature
and
people,
there
is
an
urgent
need
for
greater
understanding
of
the
complex
relationships
between
human
aes-
thetic
experience,
well-being
and
actual
or
perceived
biodiversity.
This
integrative
study
assessed
human
aesthetic
reaction,
restorative
effect
and
perceived
biodiversity
in
relation
to
fine-grained
categories
of
woodland,
shrub
and
herbaceous
planting.
We
surveyed
1411
members
of
the
public
who
walked
through
planting
of
varying
structure,
species
character
and
percentage
flower
cover
whilst
completing
a
site-
based
questionnaire.
Semi-structured,
in-depth
interviews
were
then
carried
out
with
34
questionnaire
participants.
Correlations
between
perceived
attractiveness
and
perceived
biodiversity
were
identified
for
three
out
of
four
biodiversity
indicators.
There
was
a
correlation
between
perceived
attractiveness
and
restorative
effect
yet
this
was
not
strong.
Colourful
planting
with
flower
cover
above
a
critical
threshold
(27%)
was
associated
with
the
highest
level
of
aesthetic
preference.
Subtle
green
‘background’
plant-
ing
afforded
a
restorative
effect.
These
results
are
discussed
with
reference
to
the
Circumplex
Model
of
Affect.
Our
findings
indicate
that
people
appreciate
colourful
flowering
public
planting
for
the
‘wow
factor’,
but
that
green
planting
outside
the
narrow
flowering
season
of
most
species
is
greatly
valued.
Planting
moderately
or
most
natural
in
structure
was
perceived
as
significantly
more
restorative
than
that
least
natural
in
structure
suggesting
that
people
in
the
UK
may
be
increasingly
accepting
of
a
messier
‘ecological
aesthetic’
in
urban
planting.
©
2017
The
Authors.
Published
by
Elsevier
B.V.
This
is
an
open
access
article
under
the
CC
BY-NC-ND
license
(http://creativecommons.org/licenses/by-nc-nd/4.0/).
1.
Introduction
During
the
last
decade
much
evidence
has
accrued
to
sup-
port
the
proposition
that
exposure
to
natural
environments
and
Corresponding
author
at:
Centre
for
Sustainable
Planning
and
Environments,
University
of
the
West
of
England,
Frenchay
Campus,
Bristol
BS16
IQY,
United
King-
dom.
E-mail
addresses:
Helen.Hoyle@uwe.ac.uk
(H.
Hoyle),
j.d.hitchmough@sheffield.ac.uk
(J.
Hitchmough),
A.jorgensen@sheffield.ac.uk
(A.
Jorgensen).
their
associated
wildlife
has
multiple
benefits
for
human
health
and
well-being
(for
reviews
see
Clark
et
al.,
2014;
Jorgensen
and
Gobster,
2010;
Velarde,
Fry,
and
Tveit,
2007),
yet
the
world’s
increasingly
urban
population
is
becoming
less
likely
to
have
direct
contact
with
nature
(Soga
and
Gaston,
2016).
The
need
for
urban
green
spaces
to
foster
physical
and
psychological
well-being
has
therefore
becoming
a
key
focus
of
urban
policy
(for
example,
GCV,
Green
Network
Partnership,
2016;
GLA,
2015).
Running
in
parallel
with
this
is
a
desire
to
halt
the
loss
of
biodiversity
and
ecosystem
services,
as
for
example
in
the
EU
Biodiversity
strategy
2020.
In
the
UK
a
recent
change
in
national
policy
(Health
and
Social
Care
Act,
http://dx.doi.org/10.1016/j.landurbplan.2017.03.011
0169-2046/©
2017
The
Authors.
Published
by
Elsevier
B.V.
This
is
an
open
access
article
under
the
CC
BY-NC-ND
license
(http://creativecommons.org/licenses/by-nc-nd/4.
0/).
110
H.
Hoyle
et
al.
/
Landscape
and
Urban
Planning
164
(2017)
109–123
Fig.
1.
Graphical
representation
of
circumplex
model
of
effect
from
Posner
et
al.
(2005)
adapted
to
show
impact
of
contrasting
landscape
stimuli.
2012)
and
the
adoption
of
the
National
Planning
Policy
Framework,
provide
the
opportunity
for
planners
and
landscape
architects
to
work
more
closely
with
public
health
agencies
to
create
public
green
infrastructure
which
is
popular
with
local
people,
beneficial
in
terms
of
health
and
well-being,
and
ecologically
biodiverse.
Much
contemporary
well-being
research
incorporates
mea-
sures
based
on
Attention
Restoration
Theory
(ART),
(Kaplan
and
Kaplan,
1989).
This
proposes
that
if
an
individual
is
engaged
in
a
task
which
requires
directed
attention
for
a
prolonged
period
of
time,
they
will
become
mentally
fatigued
(Staats,
Jahncke,
Herzog,
and
Hartig,
2016;
Stevens,
2014).
Recovery
(restorative
effect)
is
most
likely
within
settings
in
which
it
is
possible
to
escape
the
rou-
tine
environment
by
‘being
away’
(Kaplan,
2001);
finding
a
‘whole
other
world’,
which
provides
opportunities
for
effortless
attention
or
‘fascination’;
and
‘compatibility’
with
an
individual’s
purpose
or
intent
(Kaplan,
1995).
Natural
settings
have
these
characteris-
tics
(Herzog,
Maguire,
and
Nebel,
2003).
An
alternative
approach
focuses
specifically
on
the
human
aesthetic
response
to
contrast-
ing
built
and
vegetated
urban
landscapes
(Ulrich,
1986)
and
the
‘affective
(emotional)
response’
of
the
observer.
For
landscape
architecture
and
planning
a
major
shortcoming
of
attention
restoration
research
(Hartig
and
Staats,
2006;
Hartig,
Mang,
and
Evans,
1991;
Herzog,
Black,
Fountaine,
and
Knotts,
1997;
Herzog
et
al.,
2003;
Staats
et
al.,
2016;
Stevens,
2014)
and
ear-
lier
studies
of
human
aesthetic
response
(Berlyne,
1971;
Ulrich,
1986,
1983)
has
been
the
treatment
of
natural
spaces
as
homoge-
nous
(Clark
et
al.,
2014;
Van
den
Berg,
Jorgensen,
and
Wilson,
2014;
Velarde
et
al.,
2007).
Stevens,
(2014)
compared
the
perceived
restorativeness
of
natural
and
urban
environments
by
showing
research
participants
images
from
either
‘nature’
or
‘cities’
cate-
gories.
Staats
et
al.
(2016)
compared
the
general
preference
and
likelihood
of
achieving
psychological
restoration
in
a
park,
café,
shopping
mall
or
walking
along
a
busy
street,
with
the
‘park’
treated
as
one
homogenous
area
of
green
space.
Growing
aware-
ness
of
the
need
for
a
much
more
nuanced
understanding
of
how
the
form,
composition
and
character
of
plantings
of
trees,
shrubs
and
herbaceous
plants
are
perceived
and
preferred
has
gen-
erated
three
parallel
strands
of
literature
addressing
firstly,
the
relationship
between
varying
biodiversity
levels
and
human
aes-
thetic
preference,
secondly
the
relationship
between
biodiversity
and
restorative
effect
or
well-being
and
thirdly
the
relationship
between
varying
aesthetics
of
green
space
and
restorative
effect
or
well-being.
The
relationship
between
human
aesthetic
response
and
bio-
diversity
is
complex.
Jorgensen,
Hitchmough,
&
Dunnett
(2007)
concluded
that
residents
of
Warrington,
UK
had
both
positive
and
negative
feelings
towards
the
‘trees
and
greenery’
that
formed
the
biodiverse
‘ecological
style’
of
woodland
surrounding
their
homes.
Planting
was
perceived
as
attractive,
although
many
res-
idents
had
concerns
about
threats
to
personal
safety
related
to
lack
of
sight
lines
in
dense
planting.
A
study
by
Qiu,
Lindberg,
&
Nielson
(2013)
revealed
a
negative
relationship
between
peo-
ple’s
preferences
and
biodiversity
within
four
contrasting
habitat
zones
of
a
Swedish
park.
Participants
directed
negative
comments
towards
the
‘wild-looking’
woodlands
with
the
highest
biodiversity
value,
and
positive
ones
towards
the
ornamental
park
habitat
with
the
lowest
biodiversity
value,
perhaps
because
urban
residents
are
most
familiar
with
a
cultural
context
of
the
‘deep
pervasive
cul-
tural
norm’
of
‘care’
(Nassauer,
2011).
More
ecologically
diverse
plantings
may
be
perceived
as
messy
and
disordered
because
they
do
not
contain
the
‘cues
to
care’,
i.e.,
subconscious
indicators
of
human
intervention
in
the
landscape
such
as
clipped
edges
and
close
mown
lawns.
A
recent
study
(Palliwoda,
Kowarik,
and
von
der
Lippe,
2017)
focusing
on
human-biodiversity
interactions
at
the
individual
species-level
in
two
parks
in
Berlin
revealed
that
12%
of
total
observed
activities
involved
interactions
with
plants
based
around
‘biodiversity
experience’
as
well
as
‘consumption’
and
‘dec-
oration’.
Gobster,
Nassauer,
Daniel,
&
Fry
(2007)
focus
specifically
on
the
relationship
between
aesthetics
and
ecology,
concluding
that
future
landscape
design
should
be
able
to
create
landscapes
that
are
both
ecologically
biodiverse
and
aesthetically
pleasing.
H.
Hoyle
et
al.
/
Landscape
and
Urban
Planning
164
(2017)
109–123
111
Table
1
The
planting
typology:
The
criteria
(planting
structure
and
species
character)
used
to
define
the
nine
types
of
woodland,
shrub
and
herbaceous
vegetation
used
in
the
study.
least natural
moderately natural
most natura l
least
natural
Stru cture: Simple, largely single
layer. Isolated trees o
r shrubs,
discrete ‘blocks’ o
f
shrubs/herbaceous plants. Strong
cues to
being designed
Character
:
Mostly no n –
nati
ve
spec
ies of diff
erent appearance
to
those foun
d in relevant reference
ecosystem
Structure: Intermediate
Character:
Mostl
y non
nati
ve
spec
ies of d
ifferent appea
rance to
tho
se found in relevant reference
ecosystem
Structure: Complex, two or three
layers. Tree
s, sh rub s, a nd
herbac
eous spec ies r and
omly
mixed together. Cues to being
designed
absent.
Character:
Mostly non –
native
species of different appearance to
those found in
relevant reference
ecosystem
moderatel y
natural
Stru cture: Simple, largely single
layer. Isolated trees o
r shrubs,
discrete ‘blocks’ of
shrubs/herbaceous plants. Strong
cues to
being designed
Character: Intermediate
Structure: Intermediate
Character: Intermediate
Structure: Complex, two or three
layers. Tree
s, sh rub s, a nd
herbac
eous spec ies r and
omly
mixed together. Cues to being
designed
absent.
Character:
Intermediate
most
natural
Stru cture: Simple, largely single
layer. Isolated trees o
r shrubs,
discrete ‘blocks’ o
f
shrubs/herbaceous plants. Strong
cues to
being designed
Character: Native species with
appearance same
as/similar to
relevant reference
ec
osystem
Structure: Intermediate
Character: Nati
ve spec
ies with
appearance same as/similar to
relevant reference
ec
osystem
Structure: Complex, two or three
layers. Tree
s, sh rub s, a nd
herbac
eous spec ies r and
omly
mixed together. Cues to being
designed
absent.
Character: Native species
with
appea
rance
same as/simil
ar to
relevant
reference ecosystem
Structural similarity to natural vegetation
Species
Character
similarity
to
natural
vegetation
Over
the
last
10
years
urban
ecologists
have
sought
to
evi-
dence
and
correlate
the
health
and
well-being
benefits
of
exposure
to
green
space
with
actual
and
perceived
levels
of
biodiversity
within
green
space.
Two
studies
carried
out
in
Sheffield,
UK,
used
plant,
butterfly
and
bird
species
richness
as
biodiversity
indicators.
The
first
(Fuller,
Irvine,
Devine-Wright,
Warren,
and
Gaston,
2007)
identified
a
positive
relationship
between
self-reported
well-being
and
actual
biodiversity
levels,
whereas
the
second
(Dallimer
et
al.,
2012)
found
no
such
relationship,
yet
identified
a
positive
rela-
tionship
between
well-being
and
perceived
biodiversity.
A
recent
study
(Carrus
et
al.,
2015)
conducted
in
four
medium-to-large
size
Italian
cities
revealed
the
positive
role
of
biodiversity
upon
per-
ceived
restorative
properties
and
self-reported
benefits
for
urban
and
peri-urban
green
spaces.
Most
studies
have
identified
a
positive
association
between
aesthetic
or
visual
preference
and
restorative
effect
(Herzog
et
al.,
2003;
Laumann,
Garling,
and
Stormak,
2001;
Nordh,
Hartig,
Hagerhall,
and
Fry,
2009;
Pals,
Steg,
Siero,
and
van
der
Zee,
2009;
Pazhouhanfar
and
Kamal,
2014;
Purcell,
Peron,
and
Berto,
2001;
Tenngart
Ivarsson
and
Hagerhall,
2008;
Van
den
Berg,
Koole,
and
Van
der
Wulp,
2003),
although
the
strength
of
that
association
has
varied.
Purcell
et
al.
(2001),
observed
a
particularly
high
correla-
tion
(0.81)
between
visual
preference
and
the
Perceived
Restorative
Scale.
A
later
study
of
Norwegian
urban
‘pocket
parks’
(Nordh
et
al.,
2009)
concluded
that
restorative
effect
was
positively
related
to
the
percentage
of
grass-covered
surface
and
the
amount
of
visible
trees
and
bushes.
Pazhouhanfar
&
Kamal
(2014)
found
a
positive
relationship
between
three
out
of
four
predictors
of
visual
land-
scape
preference
(Complexity,
Coherence,
Mystery)
and
Perceived
Restorative
Potential
(PRP),
but
no
relationship
between
the
fourth
predictor,
Legibility,
and
PRP.
In
contrast,
research
focusing
on
the
impact
on
psychological
well-being
of
walking
in
‘wild’
and
‘tended’
urban
forests
(Martens,
Gutscher,
and
Bauer,
2011)
revealed
a
more
positive
well-being
affect
from
walking
in
the
latter,
yet
no
rela-
tionship
between
perceived
attractiveness
and
well-being.
Van
den
Berg
et
al.
(2014)
differentiated
between
four
setting
types;
urban
street,
parkland,
tended
woodland
and
wild
woods.
Their
findings
revealed
no
significant
relationship
between
restorative
poten-
tial
and
setting
types,
although
there
was
a
relationship
between
restorativeness
and
perceived
‘naturalness’.
We
identified
a
need
to
move
from
these
parallel
strands
of
thought
to
a
more
integrative
approach.
If
public
green
infras-
tructure
is
to
be
designed
and
managed
optimally,
the
complex
relationships
between
human
aesthetic
experience,
restorative
effect
and
well-being,
and
perceived
and
actual
biodiversity
in
relation
to
varying
‘natural’
environments
need
to
be
better
under-
stood.
A
useful
concept
to
approach
this
by
is
the
Circumplex
Model
of
Affect
(Russell,
1980).
Originally
used
in
psychology,
and
more
recently
applied
to
neuroscience
(Posner,
Russell,
and
Peterson,
2005)
the
Circumplex
Model
(Fig.
1)
can
be
used
to
understand
human
emotional
(affective)
reactions.
It
proposes
that
all
human
reactions
or
affective
states
arise
from
two
overlapping
systems;
one
related
to
valence,
a
pleasure-displeasure
continuum,
and
the
second
related
to
a
degree
of
arousal
or
alertness,
i.e.,
‘activation’
to
‘deactivation’
(Russell,
1980).
Each
emotion
is
then
understood
as
a
linear
combination
of
valence
and
alertness.
The
emotions
‘excited’,
‘elated’,
‘relaxed’
and
‘calm’
are
all
associated
with
a
posi-
tive
valence,
yet
all
involve
a
different
degree
of
‘arousal’.
The
model
has
been
applied
recently
in
the
investigation
of
children’s
experi-
ences
with
nature
in
a
botanical
garden
(Linzmayer,
Halpenny,
and
Walker,
2014).
Our
study
builds
on
this
with
a
large
sample
of
1411
questionnaire
participants,
and
a
wider
range
of
landscape
stimuli.
We
apply
the
Circumplex
Model
of
Affect
(Russell,
1980)
to
inter-
pret
varying
human
reactions
to
planted
environments.
We
focus
112
H.
Hoyle
et
al.
/
Landscape
and
Urban
Planning
164
(2017)
109–123
Fig.
2.
Images
of
actual
case
study
sites
representing
the
planting
types
defined
by
structure
&
species
character
used
in
woodland
questionnaire
surveys.
Table
2
On-site
questionnaire:
Individual
attitudinal
statements
and
questions
used
to
address
participants’
perceptions
of
the
(a)
aesthetic
qualities,
(b)
restorative
effects
(c)
biodiversity
value
of
the
planting.
Research
theme
Questionnaire
Measures
(Individual
attitudinal
statements
&
questions)
Aesthetic
qualities
The
planting
along
this
walk
is
interesting
The
planting
on
this
walk
is
attractive
The
planting
on
this
walk
looks
natural
The
planting
on
this
walk
looks
cared
for
The
planting
on
this
walk
looks
designed
The
planting
on
this
walk
looks
tidy
The
planting
on
this
walk
looks
familiar
to
me
The
planting
on
this
walk
is
colourful
The
combination
of
colours
is
attractive
in
this
planting
How
structurally
complex
would
you
describe
this
planting?
Restorative
effects
I
feel
comfortable
on
this
walk
This
walk
allows
me
to
escape
more
mundane
routines
and
work
I
feel
relaxed
on
this
walk
This
walk
reveals
a
special
unique
place
Perceived
biodiversity
value
How
many
different
plant
species
do
you
think
there
are
here?
How
many
native
UK
plant
species
do
you
think
are
in
this
planting?
The
planting
along
this
walk
appears
good
for
butterflies,
bees
and
other
insects
How
many
species
of
native
UK
insects
(flies,
butterflies,
bees)
do
you
think
this
planting
will
support?
H.
Hoyle
et
al.
/
Landscape
and
Urban
Planning
164
(2017)
109–123
113
Fig.
3.
Geographical
distribution
of
case
study
sites
(n
=
31)
throughout
England.
Fig.
4.
On-site
walks
were
marked
along
existing
paths:
RHS
Wisley,
Surrey
(a)
and
Sheffield
Botanical
Garden
(b).
on
public
perception
of
the:
aesthetic
qualities,
restorative
effect
and
perceived
biodiversity
of
the
planting.
We
investigate
whether
varying
emotions
are
triggered
by
walking
through
planting
of
a
particular
structure
and
species
character
and
with
varying
per-
centage
flower
cover.
Previous
studies
have
indicated
that
flowers
induce
powerful
positive
emotions
(Haviland-Jones,
Hale,
Wilson,
and
McGuire,
2005).
We
propose
that
planting
perceived
as
highly
attractive
may
result
in
‘excitement’
and
‘elation’.
These
emo-
tions
are
the
product
of
a
high
degree
of
‘arousal’.
In
contrast,
the
emotions
‘calm’
and
‘relaxed’
are
relatively
much
closer
to
‘deacti-
vation’.
These
calm,
relaxed
affective
responses
may
be
generated
by
less
dramatic
planting,
resulting
in
a
restorative
effect.
Inter-
preting
human
affective
response
to
varying
landscape
stimuli
via
this
framework
might
also
elucidate
the
complex
and
conflicting
evidence,
for
example
(Martens
et
al.,
2011;
Purcell
et
al.,
2001)
concerning
the
relationship
between
aesthetic
preference,
restora-
tive
effect
and
well-being.
The
research
questions
we
addressed
were
as
follows:
(a)
How
does
perceived
attractiveness
relate
to
perceived
biodiversity?
(b)
How
does
restorative
effect
relate
to
perceived
biodiversity?
(c)
How
does
perceived
attractiveness
relate
to
restorative
effect?
2.
Methods
2.1.
The
planting
typology
and
case
study
sites
A
typology
of
9
planting
types
was
first
developed
across
each
of
three
vegetation
communities:
woodland,
shrub
and
herbaceous.
Individual
planting
types
were
defined
by
gradients
in
planting
structure
and
species
character
for
each
community
(Table
1).
Structure
refers
to
the
manner
in
which
plants
are
layered
through
the
third
dimension.
Species
character
is
derived
from
the
appear-
ance
of
the
species
present
on
a
gradient
from
native
to
non-native.
These
variables
were
selected
because
they
define
the
relative
‘naturalness’
of
the
planting,
and
are
qualities
which
are
read-
ily
manipulated
in
urban
areas
by
landscape
architects.
In
the
UK
‘natural’
vegetation
is
exemplified
by
multi-layered
broad-leaved
deciduous
woodland,
shrubby
woodland
edge
and
herbaceous
communities
of
tall
grasses
and
forbs,
all
composed
of
native
species.
We
identified
three
levels
of
structure
and
species
charac-
ter
for
each
community
in
relation
to
these
reference
ecosystems:
‘most
natural’,
‘moderately
natural’
and
‘least
natural’.
These
struc-
ture/species
character
levels
interacted
to
generate
the
nine
types
114
H.
Hoyle
et
al.
/
Landscape
and
Urban
Planning
164
(2017)
109–123
Fig.
5.
Planting
at
‘The
Punchbowl’
(Valley
Gardens),
Crown
Estate.
Vibrant
planting
with
a
flower
cover
above
27%
(a)
was
considered
the
most
attractive
and
associated
with
the
‘wow
factor’,
whereas
subtle
greens
(b)
were
associated
with
a
greater
restorative
effect.
for
each
vegetation
community
(Table
1).
For
example,
in
the
case
of
woodland,
a
multi-layered
system
represents
the
‘most
natural’
structure,
and
in
contrast,
a
single
layer
of
arboretum-style
trees
represents
a
highly
designed
‘least
natural’
structure.
Broadleaved
deciduous
trees
represent
the
‘most
natural’
species
character,
whereas
broadleaved
evergreen
species
such
as
Eucalyptus
and
Cordyline
australis
are
‘least
natural’
in
species
character
(Fig.
2).
Specific
case
study
sites
were
then
identified
to
represent
the
com-
bined
structure
and
character
levels
(types)
of
relative
‘naturalness’
for
each
vegetation
community:
woodland,
shrub
and
herbaceous
(Figs.
2
and
3).
The
additional
planting
variable
‘percentage
flower
cover’
was
calculated
using
panoramic
photographs
of
the
planting
taken
by
the
researcher
during
the
on-site
walks/questionnaires.
The
per-
centage
vegetated
surface
covered
by
flower
was
recorded.
2.2.
On-site
questionnaires
Participants
(useable
sample
size
n
=
1411)
walked
through
and
observed
contrasting
areas
of
planting
that
corresponded
with
our
combined
structure/character
planting
types
within
each
of
the
three
vegetation
communities.
Surveys
were
conducted
during
different
seasons,
at
31
different
sites
within
8
locations
in
Eng-
land.
The
geographical-climatic
spread
of
sites
(Fig.
3)
facilitated
the
capture
of
the
appropriate
structure/character
combinations.
Dorset
(Abbotsbury)
and
Torquay
(Devon)
provided
examples
of
near
Mediterranean
plantings.
Many
locations,
for
example
RHS
Wisley
in
Surrey
and
Fairlands
Valley
Park
in
Stevenage,
provided
a
number
of
case
study
sites.
Each
respondent
took
part
in
one
walk
only
and
completed
a
questionnaire
as
they
walked,
commenting
on
the
planting
at
a
human
experiential
scale.
2.2.1.
Questionnaire
design
and
procedure
The
questionnaire
was
designed
to
capture
respondents’
per-
ceptions
of
the
aesthetic
qualities,
restorative
effect
and
perceived
biodiversity
value
of
the
planting
(Table
2).
A
section
focusing
on
the
respondents’
demographic
characteristics
was
also
included.
At
the
end
of
the
questionnaire
respondents
were
invited
to
leave
their
email
address
or
telephone
number
with
a
view
to
taking
part
in
a
follow-up
interview.
After
ethical
clearance,
the
questionnaire
was
piloted
in
April
and
May
2012
in
woodland
areas
at
RHS
Wisley,
Surrey
and
at
Fairlands
Valley
Park
Stevenage.
Short
(approximately
30
m)
walks
(after
Martens
et
al.,
2011)
were
established
and
marked
along
paths
through
sections
of
planting
which
best
represented
a
par-
ticular
planting
type
at
the
case
study
site
(Fig.
4).
All
site-users
walking
through
or
adjacent
to
the
marked
section
of
planting
were
approached
as
potential
participants.
Participants
had
the
oppor-
tunity
to
walk
independently
and
to
engage
fully
with
the
planting.
All
walks
were
carried
out
in
relatively
comparable
weather:
dry
days
with
low
wind
speeds.
The
limitations
of
this
method
are
that
specific
light
or
weather
conditions,
or
the
exact
configura-
tion
of
plants
cannot
be
controlled
as
in
photographs,
(Purcell
and
Lamb,
1998;
Purcell
et
al.,
2001),
digitally
manipulated
photographs
(Jorgensen,
Hitchmough,
and
Calvert,
2002;
Todorova,
Asakawa,
and
Aikoh,
2004),
or
videos
(Van
den
Berg
et
al.,
2014),
yet
we
con-
cluded
that
for
the
purposes
of
this
study
the
three-dimensional
multi-experiential
benefits
of
the
immersive
approach
outweighed
these
disadvantages.
All
(n
=
1411)
surveys
were
completed
during
spring,
summer
and
autumn
2012
and
2013.
This
comprised
595
questionnaires
at
13
different
woodland
sites,
348
at
8
different
shrub
sites
and
486
at
10
different
herbaceous
sites.
2.2.2.
Questionnaire
data
analysis
All
questionnaire
data
were
analysed
using
SPSS
version
20.
Principal
Components
Analysis
(PCA)
with
a
varimax
rotation
was
applied
to
the
data
for
all
vegetation
communities
to
identify
ques-
tionnaire
items
that
varied
in
a
consistent
pattern
and
loaded
onto
single
components,
each
measuring
specific
dimension
of
participants’
perceptions
(Table
3).
Meaningful
components
were
extracted
via
parallel
analysis
(Watkins,
2005).
ANOVA
techniques
were
then
used
to
explore
these
com-
ponents’
relationships
with
each
planting
variable
(‘structure’,
‘character’,
%
flower
cover,
‘vegetation
community’)
and
respon-
dents’
demographic
characteristics.
One-way
ANOVA
(Table
6)
was
first
conducted
with
the
emergent
perceptional
principal
compo-
nents
as
dependent,
and
planting
and
demographic
variables
as
independent,
to
identify
all
significant
planting
and
demographic
variables.
Multi-factor
ANOVA
(Table
7)
was
then
conducted
with
the
emergent
perceptional
principal
components
as
dependent
and
all
planting
and
demographic
variables
identified
as
significant
in
the
first
analysis
(one-way
ANOVA)
as
independent.
This
estab-
lished
the
independent
effect
of
the
strongest
explanatory
planting
variables,
adjusting
for
demographic
variables.
Subsequent
adjust-
ment
for
planting
variables
identified
the
independent
effect
of
the
strongest
explanatory
demographic
variables.
When
these
final
models
were
obtained,
post
hoc
multiple
comparisons
were
carried
out
using
the
Sidak
correction
to
distinguish
significant
differences
between
groups
or
categories
(Tables
8
and
9).
Pearson
correlations
were
then
carried
out
to
identify
associa-
tions
between
perceived
attractiveness
and
perceived
biodiversity,
restorative
effect
and
perceived
biodiversity
and
perceived
attrac-
tiveness
and
restorative
effect
(Table
10).
In
order
to
focus
specifically
on
perceived
attractiveness,
the
measure
used
in
this
analysis
was
the
individual
variable
relating
to
the
attitudinal
state-
ment,
‘the
planting
on
this
walk
is
attractive’
in
the
questionnaire.
The
measure
of
restorative
effect
was
the
component,
‘restora-
tive
effect’
emerging
from
the
PCA.
Perceived
biodiversity
was
measured
by
four
individual
variables
relating
to
items
in
the
ques-
tionnaire
(Table
2).
H.
Hoyle
et
al.
/
Landscape
and
Urban
Planning
164
(2017)
109–123
115
Table
3
Sorted
pattern
matrix
for
the
three
key
dimensions
of
participants’
perceptions
(n
=
1411)
emerging
from
principal
components
analysis
with
a
varimax
rotation.
Item
loading
values
>0.5
are
shown.
Components
Questionnaire
item
(Individual
attitudinal
statements
&
questions)
Aesthetic
effect
(Colour,
attractiveness,
interest
&
invertebrate
benefit)
Restorative
effect
Neatness
Perceived
native
plant
&
invertebrate
biodiversity
Unfamiliarity
&
complexity
The
planting
on
this
walk
is
colourful
0.85
The
combination
of
colours
is
attractive
in
this
planting
0.85
The
planting
along
this
walk
is
attractive
0.72
The
planting
along
this
walk
is
interesting
0.72
The
planting
along
this
walk
appears
good
for
butterflies,
bees
and
other
insects
0.59
I
feel
relaxed
on
this
walk
0.84
I
feel
comfortable
along
this
walk
0.79
This
walk
allows
me
to
escape
from
more
mundane
routines
and
work
0.76
The
planting
on
this
walk
looks
tidy
0.84
The
planting
on
this
walk
looks
cared
for
0.78
The
planting
on
this
walk
looks
designed
0.78
How
many
native
UK
plant
species
do
you
think
there
are
in
this
planting?
0.80
How
many
species
of
native
UK
insects
(flies,
butterflies,
bees)
do
you
think
this
planting
will
support?
0.72
The
planting
on
this
walk
looks
familiar
to
me
0.69
How
structurally
complex
would
you
describe
this
planting?
0.58
How
many
different
plant
species
do
you
think
there
are
here?
0.56
Variance
explained% 30.56
12.40
9.75
6.39
6.27
2.3.
Semi-structured
interviews
A
smaller
subset
(n
=
34)
of
questionnaire
respondents
vol-
unteered
to
take
part
in
a
semi-structured
in-depth
interview.
Interviews
were
conducted
to
better
understand
and
interpret
the
questionnaire
responses.
This
two-stage
approach
followed
estab-
lished
methodology,
(e.g.,
Jorgensen
et
al.,
2007).
2.3.1.
Interview
design
and
procedure
The
components
emerging
from
the
PCA
informed
the
content
and
approach
of
the
interviews.
Themes
relevant
to
this
paper
included
‘attractiveness’,
‘feeling
relaxed’,
(restorative
effect),
‘perceived
invertebrate
biodiversity’
and
‘colour
and
flowering’.
Participants
were
presented
with
a
range
of
panoramic
pho-
tographs
of
planting
types
of
varying
structure
and
species
character
at
the
case
study
sites.
These
were
of
the
same
vege-
tation
community
they
had
originally
walked
through
during
the
questionnaire
phase
(woodland,
shrub
or
herbaceous)
and
acted
as
a
cue
to
discussion.
In
addition,
in
order
to
understand
more
about
the
relationship
between
planting
perceived
as
attractive
and
that
perceived
as
relaxing
(restorative),
all
participants
were
shown
two
images
of
planting
at
one
case
study
site,
‘the
Punchbowl’
(Valley
Gardens),
one
when
it
was
in
full
flower
(in
May),
and
one
when
it
was
predominantly
green
(in
August),
(Fig.
5).
They
were
asked
firstly
which
of
these
areas
of
planting
they
would
find
the
most
attractive
to
walk
through,
and
secondly,
which
area
they
would
find
most
relaxing
to
walk
through.
They
were
then
asked
to
justify
their
views.
Interviews
were
semi-structured
and
flexible,
allowing
partici-
pants
to
diverge
from
the
themes
identified
by
the
interviewer.
An
interview
‘guide’
was
used
(after
Bryman,
2012)
allowing
the
inter-
viewer
flexibility
in
the
ordering
and
exact
wording
of
questions.
Following
ethical
clearance,
34
interviews
representing
walks
at
24
sites
(9
woodland,
8
shrub
and
17
herbaceous)
were
conducted
from
20th
March-31st
July
2014.
With
the
exception
of
three
pilot
interviews
which
took
place
in
the
University,
all
interviews
were
conducted
at
the
original
walk
sites.
All
interviews
were
audio-
recorded
and
later
transcribed
in
full.
2.3.2.
Interview
data
analysis
Interview
data
were
analysed
via
qualitative
content
analysis
(after
Saldana,
2013),
using
the
interview
themes
above
as
ini-
tial
deductive
coding
categories
(after
Mayring,
2014).
Emergent
themes
were
also
coded,
and
extracts
taking
a
particular
slant
or
standpoint
were
grouped
together
using
an
indexing
system
to
cat-
egorise
data
(after
MacQueen,
McLellan,
Kay,
and
Milstein,
1998).
116
H.
Hoyle
et
al.
/
Landscape
and
Urban
Planning
164
(2017)
109–123
Table
4
Questionnaire
participants’
(n
=
1411)
demographic
profile a(valid%).
Gender
(Overall
missing
values
=
29
respondents)
Woodland
walks
Shrub
walks
Herbaceous
Walks
Overall
M
232
(39.9%)
114
(33.4%)
178
(37.4%)
524
(37.5%)
F
349
(60.1%) 227
(66.6%) 298
(62.6%)
874
(62.5%)
Age
(Overall
missing
values
=
34
respondents)
Woodland
walks
Shrub
walks
Herbaceous
Walks
Overall
18–24
38
(6.5%)
19
(5.6%)
33
(6.9%)
90
(6.5%)
25–34
35
(6.0
%)
28
(8.3%)
43
(9.1%)
106
(7.6%)
35–44
54
(9.3%)
29
(8.6%)
53
(11.2%)
136
(9.8%)
45–54 95
(16.4%) 48
(14.2%) 95
(20.0%) 238
(17.1%)
55–64 172
(29.6%)
82
(24.3%)
114
(24.0%)
368
(26.4%)
65+
187
(32.2
%)
131
(38.9%)
137
(28.8%)
455
(32.7%)
Educational
Qualifications
(Overall
missing
values
=
123
respondents)
Woodland
walks
Shrub
walks
Herbaceous
Walks
Overall
None
87
(16.3%)
39
(12.3%)
66
(14.6%)
192
(14.7%)
GCSE/O’
level
(or
equiv)
183
(34.3%)
76
(23.9%)
115
(25.4%)
374
(28.7%)
A
level
(or
equiv) 86
(16.1%)
61
(19.2%)
83
(18.3%)
230
(17.6%)
Degree
127
(23.8
%)
104
(32.7%)
128
(28.3%)
359
(27.5%)
Masters’
degree
36
(6.8%)
28
(8.8%)
49
(10.8%)
113
(8.7%)
Doctorate
14
(2.6%)
10
(3.1%)
12
(2.6%)
36
(2.8%)
Landscape
professional?
(Overall
missing
values
=
482
respondents)
Woodland
walks
Shrub
walks
Herbaceous
Walks
Overall
Yes
11
(3%)
10
(3.9%)
11
(3.4%)
32
(3.4%)
No
353
(97%)
246
(96.1%)
314
(96.6%)
913
(96.6%)
aValid
percentages
given
due
to
missing
values.
Table
5
Interviewees’
(n
=
34)
demographic
profile.
Gender
Woodland
walks
(n
=
9)
Shrub
walks
(n
=
8)
Herbaceous
Walks
(n
=
17)
Overall
(n
=
34)
M
5
(56%)
4
(50%)
5
(29%)
14
(41%)
F
4
(44%)
4
(50%)
12
(71%)
20
(59%)
Age
25–34
0
1
(12.5%)
2
(12%)
3
(9%)
35–44 1
(11%)
0
2
(12%)
3
(9%)
45–54
3
(33%)
2
(25%)
2
(12%)
7
(21%)
55–64
5
(56%)
2
(25%)
4
(23%)
11
(32%)
65+
0
3
(37.5%)
7
(41%)
10
(29%)
Educational
qualifications
Woodland
walks
(n
=
9)
Shrub
walks
(n
=
8)
Herbaceous
Walks
(n
=
17)
Overall
(n
=
34)
None
2
(22%)
0
1
(6%)
3
(9%)
GCSE/O’
level
(or
equiv)
1
(11%)
3
(37.5%)
2
(12%)
6
(18%)
A
level
(or
equiv)
0
1
(12.5%)
7
(41%)
8
(23%)
Degree
6
(67%)
3
(37.5%)
4
(23%)
13