Research Design Connections
Studies examine the retail value of trees, psychological
effects of roadside plantings, and not driving in national parks.
By Sally Augustin and Jean Marie Cackowski-Campbell, ASLA
Studies examine the retail value of trees, psychological effects of roadside
plantings, and not driving in national parks.
By Sally Augustin and Jean Marie Cackowski-Campbell, ASLA
Landscape Architecture, in partnership with the web-based newsletter
and daily blog Research Design Connections, uses this column to report
current research of interest to landscape architects from a wide array of
disciplines. We welcome your comments, suggestions about future topics, and
studies you have encountered in your own practice.
Trees Earn Their Keep
Recent research by Kathleen Wolf builds on previous studies that show the
positive effects of trees on judgments of visual quality and, in particular,
on consumer behavior. Two studies by Wolf, reported together, indicate that
trees increase people’s positive perceptions of central business districts
in cities and towns of various sizes, generate shopping activity, and enhance
perceptions of product pricing. Wolf says she was motivated to conduct her
survey-based research because few marketing studies “have looked beyond the
door of the store to assess the consequences of streetscape character and
Wolf presented study participants with images of business districts with
varying numbers of trees. The responses revealed that:
- Participants consistently valued the presence of trees in images
presented to them. “Image categories depicting business district
settings having tidy sidewalks and quality buildings but no trees
were at the low end of the preference ratings. Images having well-tended
large trees received the highest preference ratings, even though
plants obscured other elements (such as historic buildings) that
often are the targets of business-improvement programs.”
- Participants valued both openly pruned and densely canopied
trees, which indicates that trimming trees for better visibility
of buildings or storefronts doesn’t diminish shoppers’ positive
responses to the trees.
From these responses, Wolf concludes that “limbing up” and thinning the canopies
of large trees “is a better management strategy for visual quality enhancements
than topping [trees] at sign levels or planting smaller trees [whose] mature
canopy height is the same as business windows and signage.” The study also
linked the presence of trees to more positive conjectures about in-store experiences.
“Judgments of products and merchants were more positive in forested places
as were inferences about product value, product quality, and merchant responsiveness,”
Wolf notes. “Respondents infer that the green streetscape has more positive
atmosphere, image, and comfort level and would be a more favorable place to
visit and dine out.”
Participants reported that once drawn to sylvan streetscapes, they would
be willing to pay more for parking, goods, and services in areas with trees.
These increased parking fees, along with the increased store revenue that
can reasonably be associated with the longer time periods that people indicated
they would spend in areas with trees, may provide the needed financial support
for tree planting in shopping districts.
“Business District Streetscapes, Trees, and Consumer Response,”
by Kathleen Wolf; Journal of Forestry, vol. 103, no.
- “Trees in the Small City Retail Business District: Comparing Resident and
Visitor Perceptions,” by Kathleen Wolf, Journal of Forestry, vol. 103,
no. 8, 2005.
Landscape Improves Road Safety
Is the roadside landscape a stress buster or a fender bender? Environmental
psychologists have argued the first point, while transportation researchers
have often argued the second, because of the seriousness of vehicle/tree collisions
and the potential for designed roadside landscape to distract drivers. Recent
research in Texas allows environmental psychologists to chalk up a point for
The study, by Jeong-Hun Mok, Harlow Landphair, ASLA, and Jody Naden, reports
that along 10 test sections of road, planted roadside landscape was linked
with a significant decrease in crash rates. The researchers chose study sites
in eight different cities. Eight of the study locations were on interstate
or major arterials, and two were on city streets. The authors analyzed data
collected by state agencies on 5,874 crashes during the three- to five-year
periods before and after the landscape changes took place. The analyses included
all types of crashes that occurred along these sections of road, although
the researchers eliminated crashes during the year the landscape plantings
were made, because the landscape had not yet assumed its final form.
The authors say that “the results show that there was a significant decrease
in crash rates after landscape improvements,” and “the calculated reduction
factor of tree collisions shows a decrease of about 70.83 percent on tree
collisions after landscape treatments at 10 study locations.”
Mok and his colleagues conclude that “the use of roadside plantings is having
a positive effect on overall performance and can be used as a tool to improve
the safety performance of urban streets.” The authors also recommend that
“when developing urban corridors, consideration should be given to the development
of the landscape as an integral part of the safety management within the corridor.
The landscape not only contributes to greater aesthetic compatibility between
the urban environment and the highway but may contribute to a safer street.”
“The Landscape Improvement Impacts on Roadside Safety in Texas,” by
Jeong-Hun Mok, Harlow Landphair, ASLA, and Jody Naden; Landscape and
Urban Planning, vol. 78, 2006.
Over the Hills and Through the Woods—in Yosemite
Automobile-based transportation has traditionally reigned supreme within
the national park system and has always been the primary mode of transportation
to the parks. Within the parks, this has “contributed to traffic congestion,
parking shortages, visitor crowding, localized air pollution, noise pollution,
wildlife impacts, and roadside vegetation disturbance,” researcher Dave White
notes. This has led Congress to allocate funds to encourage alternative modes
of transportation within the national park system. Several national parks,
including Yosemite, have promoted walking and bicycling and introduced alternative
transportation systems such as buses, trams, and other group transportation.
Although White reports some details of these options in other parks, his research
focuses on the system in Yosemite, which promotes buses, bicycling, and walking.
Under the right conditions, Americans visiting national parks are amenable
to using alternative transportation rather than their own vehicles while in
the park. According to White, some of the influences on the use of alternative
transportation in Yosemite National Park included previous experiences in
the park and with public transportation (in other national parks or outside
them), features of the transportation system, and the length of their visit.
This research, he writes, begins to “suggest approaches for shaping the way
Americans visit and experience their national parks to encourage environmental
White used in-park interviews with 160 visitors to collect the data for this
study. The interviews revealed that a host of individual psychological factors
as well as situational influences affect whether visitors choose alternative
transportation. The interview method allows the researcher to probe, interactively,
topics of interest with interviewees, which is not possible with a static,
White’s comprehensive study found:
Interviewees linked use of their private automobile within
the park to convenience, scheduling freedom, control, and unique
access to park features. Nearly all of those interviewed linked
car use with convenience
Visitors also related private automobile use to traffic,
crowding, and getting lost. Visitors did not generally view
these problems as very important or as detracting from their
enjoyment of Yosemite.
Visitors see the Yosemite bus shuttle as eliminating problems
related to traffic, parking, and getting lost. People chose
to use the shuttle when they experienced traffic and parking
issues. Their criticisms of the shuttle generally related to
crowding, wait times, scheduling, and routes.
Visitors reported that walking and bicycling within the park
allowed them “to take their time, focus on their immediate surroundings,
move at their own pace, and connect to the park and its natural
and cultural features in an environmentally friendly way.” They
viewed bicycles, in particular, as a faster, freer, and more
environmentally friendly way to travel between two points than
either buses or cars.
Interviewees were most likely to be walking or riding bicycles
when their most significant or memorable park experiences took
More than half of the people who participated in this study
felt that alternative transportation should be encouraged within
Yosemite, particularly as these modes are environmentally responsible,
reduce crowding, alleviate traffic and parking problems, and
encourage meaningful experiences. They positively viewed alternative
transportation both within the park and to the park.
The research indicated that if visitors had had positive experiences
with other alternative transportation in national parks, they would have
a more positive response to Yosemite’s alternative transportation.
White concludes the article by suggesting that park managers maximize the
convenience, accessibility, and flexibility of park shuttles and communicate
to visitors that alternative transportation is the more environmentally friendly
choice. Also, visitors should be made aware of the connection between walking
and bicycling and meaningful park experiences.
- "An Interpretive Study of Yosemite National Park Visitors’
Perspectives Toward Alternative Transportation in Yosemite Valley,"
by Dave White; Environmental Management, vol. 39, 2007.
Sally Augustin, RDC’s senior editor, is an environmental psychologist. Jean
Marie Cackowski-Campbell, ASLA, is the publisher of Research
Design Connections and has an MLA degree from Ohio State University.
What's New |
LAND | Annual
Product Profiles & Directory