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Gathright et al.: Tree-Assisted Therapy
Arboriculture & Urban Forestry 2008. 34(4):222–229.

Tree-Assisted Therapy: Therapeutic and Societal Benefits
from Purpose-Specific Technical Recreational
Tree-Climbing Programs
John Gathright, Yozo Yamada, and Miyako Morita
Abstract. This article explains how program design can increase the therapeutic and societal benefits from programs focused ontechnical recreational tree-climbing. We compare a recreational program with a tree-assisted therapy program that includes
purpose-specific therapeutic, educational, and motivation elements. We find that the additional elements included in the treeassisted therapy program were effective in enhancing the benefits from the tree-climbing activity.
Key Words. Community forests; environmental psychology; mood states; outdoor recreation; societal benefits; tree-assisted
therapy; tree-climbing; urban forests.

Since its inception, technical recreational tree-climbing (TRTC)
has grown rapidly in popularity. This style of tree-climbing istechnical in the sense that it involves specialized equipment andtechniques. It is recreational in the sense that it is designed to besafe and accessible for people of all ages and all levels of physical ability. The equipment and techniques of TRTC are different
than those used by professional arborists. TRTC is slower thanprofessional technical tree-climbing and strives to minimize
harm to trees and forests. Local, national, and international organizations of TRTC enthusiasts typically espouse respect andconservation of trees and forests and strive to foster a sense ofcommunity among local tree-climbers and to make TRTC accessible and safe for beginners.
A rich literature has established that exercise and other activities in nature have restorative and therapeutic benefits (Ulrich
1981, 1983, 1984; Kaplan and Kaplan 1989; Hartig et al. 1991,
2001, 2003; Ulrich et al. 1991; Kaplan 1995; Kira 2006; Van
Den Berg et al. 2007). Bodin and Hartig (2003) find that runningin outdoor greenspaces reduces anxiety, depression, and anger
more than running in an urban environment. Morita et al. (2007)
find that hostility and depression decrease and vitality increases
when walking in the forest as compared with walking in an urban
environment. From a Japanese perspective, Uehara (1999a,
1999b) finds that forest therapy can have mental and physicalhealth benefits for participants and Park et al. (2007) find thattaking in the forest atmosphere while walking and resting effectively contributed to participants’ ability to relax and produced asignificant positive sense of well-being. In Taiwan, Chang et al.
(2007) found that wilderness environments can have restorative
human well-being and psychophysiological values and benefits
for Taiwanese adults
Gathright et al. (2006) find that TRTC can also have importanttherapeutic benefits for individuals. In addition, Gathright et al.
(2007) demonstrate that tree-climbing can be socially beneficial
in the sense that tree-climbing affects participants in a mannerthat makes them more environmentally conscious. The objectiveof the present article is to study how a community program of©2008 International Society of Arboriculture

TRTC can be designed to enhance these therapeutic and societal
benefits.
In these earlier studies, tree-climbing program participants
with greater understanding of and appreciation for trees andforests experienced greater therapeutic benefit from treeclimbing activities. These same participants were also more
likely to be affected in ways beneficial to society. These observations suggest the following hypothesis that we test in thisstudy: greater therapeutic and societal benefits of TRTC can beachieved by complementing tree-climbing activities with purpose-specific therapeutic, motivational, and educational elements. We find evidence in favor of this hypothesis.
We also verify the observation that greater affinity for forests
explains better outcomes from participation in tree-climbing activities. The subjects in our experiment are not self-selected into
the program but participate as part of employer-sponsored activity. We find that that strength of a subject’s affinity for forests
is an important determinant of outcomes of interest.
Our methodology also permits us to identify the benefits of thetree-climbing programs distinct from benefits derived by participants from being in the forest setting.

METHODS
Experiment Design
We tested our hypothesis by randomly assigning subjects toparticipate in one of two programs: tree-climbing (TC) or treeassisted therapy (TAT). Both programs were introduced to participants as tree-climbing, and the participants were not told that
there were two different programs. To measure the impact of the
programs on the participants, the participants completed surveys(discussed subsequently) regarding their emotions and perceptions before, during, and after their participation in one of the
programs.
The two programs differed only in that the TAT program
included purpose-specific therapeutic, educational, and motivational elements that were not part of the TC program. We will
first describe the TC program and then we specify in what ways

Arboriculture & Urban Forestry 34(4): July 2008

223
Table 2. Subject groups.

Table 1. Tree-climbing program design elements.
Elements

TC

TAT

Group

NumberSpecies

GenderCourse“Break the ice” self-introduction game
Low-impact root protection by collecting leaves
Self-introduction
5 min “act like a tree” stretch
5 min stretch
Demonstration
Forest appreciation“Breathe like a tree”
Touch and Hug The Tree
Free tree-climbing
Treetop Relax Time
Climb down
“Tree and People” picture presentation

X
X
嘷
X
嘷
嘷
X
X
嘷
嘷
X
嘷
X

嘷
嘷
X
嘷
X
嘷
嘷
嘷
嘷
X
嘷
嘷
嘷

KMTT
KMTC
KFTT
KFTC
HMTT
HMTC
HFTT
HFTC

26
27
26
27
26
26
25
25

KonaraKonaraKonaraKonaraHinokiHinokiHinokiHinoki

Male
Male
FemaleFemaleMale
Male
FemaleFemaleTree-assisted therapy
Tree-climbing
Tree-assisted therapy
Tree-climbing
Tree-assisted therapy
Tree-climbing
Tree-assisted therapy
Tree-climbing

TC ⳱ tree-climbing; TAT ⳱ tree-assisted therapy.

the TAT program was different. Table 1 compares the design
elements of the two programs.
Tree-Climbing Program
The TC program was designed with the goal of providing an
enjoyable outdoor experience in a relaxed and informal setting.
For this program, the participants assembled in a designatedclimbing area where equipment was already in place (climbing
ropes in the trees). The program began with a short safety andequipment explanation and 5 min of stretching and warm up, 3
min for participants to introduce themselves to the group, 5 minfor each participant to put on the climbing gear, and a 5 mintree-climbing demonstration by the instructor.
The participants were then allowed to select a rope to climb
and encouraged to climb to the treetop, spend some time in thetree, and then descend as they pleased. Participants were invited
to observe other climbers, climb again, or talk with friends until
the end of the session. The tree-climbing session was designed to
be fun and enjoyable but did not include any specific therapeutic
design or forest and tree education.
Tree-Assisted Therapy Program
Like the TC program, the TAT program was designed with thegoal of providing an enjoyable outdoor experience in a relaxed
and informal setting. The TAT program was also designed toaccomplish three additional objectives. First, the program wasdesigned to be therapeutic from a restorative and emotional well-Figure 1. Mean age of each group.

being perspective. The second objective was educational: to increase participants’ understanding of and appreciation for trees
and forests. The third objective was to motivate participants to be
more environmentally conscious in their behavior.
The TAT program began with a short “break the ice” game.
There followed a 5 to 10 min tree and forest appreciation sessionin which the head instructor discussed the tree that was to be
climbed, the forest, and forest conservation issues in Japan. Participants then collected leaves from the forest to cushion theroots from the impact of the climbing activity. Next was a brief
deep-breathing exercise in which participants were to “breathe
like a tree.” The instructor explained that trees are the lungs ofthe earth, that they breathe the air that we exhale, and that webreathe the air exhaled by trees. Participants then put on treeclimbing gear and went through safety and climbing instructions.
Before climbing, each participant touched the tree as a sign ofrespect. The instructors encouraged the climbers to spend 10 ormore minutes in the treetop to observe and to reflect about natureand themselves. The participants then slowly descended as agroup. The remaining 15 min of the TAT program included apresentation and discussion about trees overcoming natural obstacles and time for participants to share their treetop observations.
Both the TC and TAT programs took a little longer thanscheduled by 5 to 10 min.
The number of instructors, climbing height (8 to 11 m [26.4 to36.3 ft]), equipment, and procedures were exactly the same forboth the TC and the TAT programs. Both programs used thesame trees, only at different times. The weather and temperatures
were very similar (sunny and warm) for all sessions.

Setting

The experiment was conducted in cooperation with Tree Climbing Japan (TCJ) at their location in Seto, Japan. Established in

Figure 2. Differences in tension–anxiety from before and after
programs. Statistical significance by the unpaired t-test**P < 0.01, *P < 0.05.
©2008 International Society of Arboriculture

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Gathright et al.: Tree-Assisted Therapy

Figure 3. Differences in anger–hate from before and after
programs. Statistical significance by the unpaired t-test**P < 0.01, *P < 0.05.

Figure 5. Differences in confusion from before and after programs. Statistical significance by the unpaired t-test**P < 0.01, *P < 0.05.

2000, TCJ has assisted more than 45,000 individuals to enjoy thebenefits of tree-climbing. In these 7 years, the demographics of
TCJ participants have changed from only small groups withspecial needs to include large groups who desire a combinationof therapeutic and environmental educational elements and exhilarating tree-climbing activities.

bark rarely peels or shows evidence of wear after tree-climbing.
Konara trees historically were used for making firewood andcharcoal and not considered to have any particular religious
value. Each group was assigned to one of two tree-climbing
areas, the grove of Hinoki trees or the grove of Konara trees.
Although the trees varied in height, this experiment was designed so that the rope anchors allowed for climbing zone between 8 and 11 m (26.4 to 36.3 ft) in both trees.

Tree Species

This study also considers the selection of species of tree to climb.
In our previous research (Gathright et al. 2007) and, also in the
research of Coss and Moore (2002) and Wolf (2004), it is apparent that people have definite visual and climbing tree preferences. In the current study, we explore the implications of these
preferences by using both Hinoki (Cypress Chamanecyparis obtuse Sieb. et Zucc) and Konara (Quercus serrata Murry) trees.
The field used in the experiment consisted of a small grove of
Hinoki trees and a grove of predominantly Konora trees. The
Hinoki and Konara trees were both approximately 60 to 85 years
old. The Hinoki trees were between 23 and 27 m (75.9 and 89.1ft) in height with a trunk diameter of 74 to 77 cm (29.6 to 30.8
in). The Konara trees were 18 to 21 m (59.4 to 69.3 ft) in heightwith trunk width of 0.69 to 73 cm (0.28 to 29.2 in). Hinoki trees
can be described as an evergreen tree with a conical shape, whichreaches heights of approximately 40 m (132 ft). The dark green
scale-like leaves will turn brownish in winter. The red–brownbark tends to peel and create bark dust while climbing. Hinoki
trees are highly valued in Japan for their religious significance aswell as for soft white wood.
Konara are deciduous trees with serrated leaves, wide open
crowns, and hard, thick white bark, which is very durable. The

Figure 4. Differences in fatigue from before and after programs. Statistical significance by the unpaired t-test**P < 0.01, *P < 0.05.
©2008 International Society of Arboriculture

Subjects

The total number of subjects who participated in one of the two
programs was 209. The assignment to groups was designed tocreate groups that included similar age and gender demographics
as well as similar size. The mean age and lower and upper agesof participants is relatively constant for all eight groups as illustrated in Figure 1. Distribution over marital status and number ofchildren is also relatively constant across the groups. The participants did not know with whom they would be grouped until
just before the programs started. Each group participated in either a TC program or a TAT program.
Research on the therapeutic impact of outdoor activity often
suffers from selection bias in that the participants are those whochoose the activity. In the study of the physiological benefits ofwalking in the forest by Morita et al. (2007), 95% of the participants had a previous favorable impression of walking in forests. Previous tree-climbing research studies were also conducted with subjects who had a desire to be in the forest and toparticipate in outdoor activities (Gathright et al. 2006, 2007).
The current study may suffer less from selection bias because
the participants for both the TC program and the TAT program

Figure 6. Differences in vitality from before and after programs. Statistical significance by the unpaired t-test**P < 0.01, *P < 0.05.

Arboriculture & Urban Forestry 34(4): July 2008

225

Table 3. P values of three factors variance analysis of POMS differences between before and after the program.
Factors

Tension/Anger

Depression

Anger/Hate

Vitality

Fatigue

Confusion

Konara–Hinoki
Therapy–tree-climbing
Male–female

0.0011
1.80E–05
0.0044

2.27E–08
0.0002
4.02E–05

0.00040.00530.00090.0001
2.40E–05
0.02650.11010.00110.02370.0635
5.12E–10
0.0610Italic bold type is 1% significant.
Italic type is 5% significant.
POMS ⳱ Profile of Mood States.

We find strong evidence that program design can increase thetherapeutic benefits derived from a tree-climbing program. Subject groups of participants in the TAT program exhibitedchanges in the mean POMS measures that were more favorable
than the changes measured in comparable subject groups of TC
participants. We discuss the comparison between programs foreach of the POMS measures.
Participation in the TAT program is associated with a greater
decrease (or smaller increase) in tension–anxiety than is participation in the TC program (Figure 2). Subject groups that climbed
Konora trees in the TAT program had a greater decrease in mean
measured tension–anxiety than the comparable groups of subjects who climbed the same trees in the TC program. For women
who participated in the TAT program and climbed Konara trees,
this larger decrease in mean measured tension–anxiety was
highly statistically significant.
For men who climbed Hinoki trees as part of the TAT program, the mean measured tension–anxiety increased, but the increase was lower (P < 0.05) than for comparable subjects in the
TC program. For women who climbed Hinoki trees as part of the
TAT program, the mean measured tension–anxiety decreased,
and the difference between that decrease and the increase inmean measured tension–anxiety for the comparable subject
group in the TC program was highly statistically significant.
An increase in tension while climbing a Hinoki tree can possibly be explained in part by the nature of the tree. The Hinoki
tree bark is easily scuffed off and the dust can be irritating for
climbers below.
The mean measured anger–hate levels decreased more forsubject groups of TAT participants (Figure 3). This greater decrease was highly statistically significant for women climbing
Hinoki trees.
The mean of the measure of fatigue for subject groups of TC
participants was higher after participating in the program (Figure4). Subject groups of TAT participants were measured to havedecreased fatigue or a smaller increase in fatigue than their comparison subject groups.
For men climbing Hinoki trees, fatigue decreased relative to
before the program, and the difference between this decrease andFigure 7. Differences in affinity for forests from before andafter programs. Statistical significance by the unpaired t-test**P < 0.01, *P < 0.05.

Figure 8. Differences in willingness to try new forest activities
from before and after programs. Statistical significance by
the unpaired t-test **P < 0.01, *P < 0.05.

were part of a company-sponsored outdoor activities agenda that
included tree-climbing. The participants were all factory workers
from several factories of a Japanese corporation.

Questionnaires

The questionnaires consisted of three sets of six-point polar format questions and a Profile of Mood States (POMS) evaluationof six mood states. Evaluation was conducted before, during, andafter each program. Before the participants entered the treeclimbing area, they were asked to complete a POMS instrument
and a questionnaire about age, gender, marital status, tree andforest appreciation, frequency of forest activities, desire to try
forest activities, conservation consciousness, opinion on the environment, and other personal background information. The participants were then divided into their assigned groups for thetree-climbing activities. After they returned to the ground, asecond POMS instrument was administered. After the program
had completed, a final questionnaire was administered.

Analysis

For the purpose of analysis, we categorized the subjects into
eight subject groups based on program, gender, and species oftree climbed (Table 2). The subject groups are unrelated to theclimbing groups discussed previously. The questionnaire data
were analyzed by taking the mean difference between the before
and after responses on each question for each subject group.
In addition, we conducted a multifactor analysis of varianceand calculated Spearman correlation coefficients as needed.

RESULTS
Program Design and Therapeutic Benefits
from Tree-Climbing©2008 International Society of Arboriculture

226

Gathright et al.: Tree-Assisted Therapy

Figure 9. Differences in perception of trees as friends frombefore and after programs. Statistical significance by the unpaired t-test **P < 0.01, *P < 0.05.

Figure 11. Differences in willingness to help forests from before and after programs. Statistical significance by the unpaired t-test **P < 0.01, *P < 0.05.

the increase measured for the men who climbed Hinoki trees
under TC was statistically significant. The smaller increase inmean measured fatigue for women climbing Hinoki trees under
TAT instead of TC was highly statistically significant.
Subject groups of TAT participants had lower mean measuresof confusion after the program (Figure 5). Contrastingly, three offour TC subject groups experienced modest increases and one avery slight decrease in the mean measure of confusion. The
differences in the changes between the two programs were statistically significant for all subject groups.
Confusion can be taken to mean not fully comprehending asituation or having the time to take appropriate action to deal
with a negative situation. It is also derived through not having
the specific emotional or physical ability to deal with a challenge
or problem. The TAT program was designed to give the participants more time to appreciate trees, observe and learn about trees
and the environment. It also gave them more time to think about
how they would descend from the treetop. These elements may
explain the greater decrease in confusion among TAT participants.
Mean measured vitality increased more for subject groups of
TAT program participants than for comparable subject groups in
the TC program (Figure 6). The greater increase was statisticallysignificant for women.
The TAT program included elements such as understanding
trees, breathing with trees and touching trees as well as time tosimply be aware of self and space while in the tree. According to
Smith and Lloyd (2006), vitality is also connected to curricularconcepts of body awareness, space, time, and relationships. The

increased vitality reported after TAT programs suggests that theaffinity with trees and time allotted for treetop observation factored into the increased vitality in the TAT programs.
This evidence on the impact of program design on the moodstate differences is corroborated by the results of the factor variance analysis. The results of this analysis lead to the rejection of
the null hypotheses that program design is unimportant in explaining individual differences in changes to each of the POMS
levels before and after program participation (Table 3). These
results of the factor variance analysis are highly statisticallysignificant.

Figure 10. Differences in perception that trees are importantfrom before and after programs. Statistical significance by
the unpaired t-test **P < 0.01, *P < 0.05.
©2008 International Society of Arboriculture

Program Design and Societal Benefits
from Tree-Climbing

Comparison of changes in the means of reports about perceptions of forests and other attitudes for participants of the two
programs indicates that the TAT program affected greater improvements in these perceptions and attitudes.
Participants in TAT expressed, on average, a more dramaticincrease in their affinity for forests from before the program toafter the program than did the TC participants (Figure 7). The
comparisons between the groups were statistically significant(highly so for men climbing Hinoki trees).
TAT participants reported a greater increase in willingness totry a new forest activity than did TC participants (Figure 8).
Except for men climbing Hinoki trees, these differences in thechanges were statistically significant.
TAT participants reported a greater increase in their feelings
that trees are friends (Figure 9). For men climbing Konora trees,
this greater increase was statistically significant, and for all theother groups, it was highly statistically significant. The conceptof trees as friends may have been unfamiliar to many participants. The postprogram responses may indicate that the concept
was better understood and appreciated by participants, especiallyby the TAT program participants.
TAT participants reported a greater increase in their feelings
that trees are important (Figure 10). For men climbing Konara
trees, this greater increase was statistically significant, and for all
the other groups, it was highly statistically significant.
All TAT subject groups reported a greater increase in their
willingness to participate in a physically demanding activity tohelp community forests than did their respective comparable TC
subject groups (Figure 11). All of the differences in changes
were highly statistically significant.

Arboriculture & Urban Forestry 34(4): July 2008

227

Table 4. P values of factor variance analysis of five differences from before and after programs.
Factors

Like forests

Try act. forest

Tree friend

Tree import

Help forest

Konara–Hinoki
Therapy–tree-climbing
Male–female

0.1218
7.09E–09
0.01030.76083.03E–05
0.00420.0141
6.42E–09
2.59E–09

0.5166
9.96E–18
0.03590.7531
1.02E–18
2.31E–07

Italic bold type is 1% significant.
Italic type is 5% significant.

Factor variance analysis indicates that program design explains variation in the changes in perceptions about forests thatcome from a tree-climbing program. The explanatory power ofthe program design is statistically significant for each of theperceptions considered (Table 4).

Program Design and Tree-Climbing Enjoyment

Factor variance analysis indicates that program design is important in explaining the variation observed in participants’ reported
perceptions of the tree-climbing program (Table 5). The explanatory power of program design was highly statistically significant
for each of the program perceptions measured.
As far as the question of whether tree-climbing itself was a fun
activity, more TAT participants responded “very fun” than did
TC participants. Among the responses from TAT participants,
there were no “not very fun” responses, but there were somefrom TC participants. The majority of responses from TAT participants ranged from “enjoyable” to “very fun.” The majority ofanswers for the TC program ranged from “sort of fun” to “fun.”
When asked if tree-climbing was pleasant, responses of “alittle unpleasant” were noticed in all four of the TC program
groups, whereas there were no “a little unpleasant” responses forany of the TAT program groups. The TAT program groups were
the only groups that also indicated that the tree-climbing activity
was “very pleasant” with the Konara Female Tree Assisted
Therapy Group (KFTT) group indicating the largest “very pleasant” response.
Concerning the satisfaction of participants with the treeclimbing activity, it is interesting to note that none of the TAT
program groups responded “dissatisfied” compared with the TC
groups that indicated various percentages of “dissatisfaction.”On the whole, the TAT program produced the most satisfaction
for all eight groups.
TAT programs produced a greater sense of accomplishment inparticipants compared with the TC program. A small percentageof participants in each of the four TC program groups reported
that they were “not sure” if they felt any sense of accomplishment after tree-climbing. The “not sure” response was not given
by any TAT program participants.
Climbing a large tree was a first-time experience for all participants in all eight groups. The greater overall impression ofaccomplishment after the TAT program may indicate that thesense of accomplishment was not only felt for the tree-climbing
activities, but also for having gained a greater knowledge of trees
and forests.
Participants in the TAT program also rated the quality andsafety of the program significantly higher than TC subjects.
Given the previous results, it is surprising to note that TAT
participants found tree-climbing more stressful. A possible explanation is that TAT program design included more relaxing
nontree-climbing elements and that in comparison to these activities, the tree-climbing activity was a more stressful activity.

Affinity for Forests and Perceptionsof Tree-Climbing

We found strong and statistically significant correlations between the affinity for forests reported by subjects before theprogram and many of the outcomes of interest.
Five of the eight subject groups had statistically significant
correlations between affinity for forests and how fun they foundtree-climbing. All of these correlations were positive (Table 6).
The findings were similar for correlation between affinity forforests and postprogram reports of satisfaction with the treeclimbing activity whether the activity was relaxing, pleasant, andwhether the activity induced a sense of accomplishment.
For the reports of whether tree-climbing was scary and stressful, the correlations were statistically significant for some subject
groups. All of these correlations were negative.

Other Results

We have noted that the factor variance analysis indicated that
program design was important in explaining the variation in allof the outcomes of interest. The other two factors that proved
important for explaining the remaining variation were tree species and gender.
Tree species was found to be an important explanatory variable for perceptions about whether tree-climbing was fun, scary,and pleasant. It was also important for explaining whether aparticipant’s belief that trees are friends was strengthened by the
program. The species of tree climbed was also an important
determinant of changes in tension–anxiety, depression, anger–
hate, and vitality.

Table 5. P values of factor variance analysis of seven perceptions from after programs.
Factors

TC funTC scary

TC pleasant

TC satisfaction

TC relax

TC stress

TC acomp

Konara–Hinoki
Therapy–tree-climbing
Male–female

0.0018
9.82E–07
0.0523

1.93E–05
2.08E–09
0.08150.0166
2.60E–13
0.71480.41203.97E–10
0.02950.7219
2.61E–11
0.00010.2501
6.46E–10
0.00110.2071
1.34E–05
0.0002

Italic bold type is 1% significant.
Italic type is 5% significant.
TC ⳱ tree-climbing; acomp ⳱ accomplishment.

©2008 International Society of Arboriculture

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Gathright et al.: Tree-Assisted Therapy

Table 6. Spearman correlation coefficients between affinity for forests and perceptions of programs.
Group

Visit forests

Try act. forests

TC funTC scary

TC pleasant

TC satisfaction

TC relax

TC stress

TC acomp

KMTT
KMTC
KFTT
KFTC
HMTT
HMTC
HFTT
HFTC

0.87320.59070.67780.6716
0.61830.60390.87320.79020.87210.92170.72800.85910.6577
0.63330.87210.88290.6838–0.6294–0.4516–0.48420.75150.50210.44290.4073–0.56620.64550.4520–0.5662–0.44120.64550.39480.51620.68380.41430.4042–0.6294

0.75150.50210.42820.4073

Italic bold type is 1% significant.
Italic type is 5% significant.
TC ⳱ tree-climbing; acomp ⳱ accomplishment.

For perceptions of the program, gender was an important explanatory factor for satisfaction with the program and perceptions about whether tree-climbing was stressful, whether it was
relaxing, and whether it induced a sense of accomplishment.
Gender helped explain changes in each of the perceptions andbeliefs about forests. Gender was important for explaining all
POMS changes except confusion.

CONCLUSION

We have tested the hypothesis that greater therapeutic and societal benefits from a community program of TRTC can beachieved by complementing tree-climbing activities with purpose-specific therapeutic, motivational, and educational elements. We have presented strong evidence in favor of this hypothesis. In particular, we have found that the participants of atree-climbing program that was enhanced with these elements(called tree-assisted therapy) experienced greater improvement
in emotional well-being and greater increase in appreciation andsympathy for the environment than did a control group in atree-climbing program without these elements.
Our comparison of tree-assisted therapy with the control program found greater reductions in participant tension, anxiety,depression, and anger and a greater increase in participant vitality. Participants in the tree-assisted therapy program also reported greater improvement in environmentally conscious attitudes. In addition, we found that the tree-assisted therapy program provided a more enjoyable and relaxing tree-climbing
experience for participants.
We have also established that participants’ affinity for trees is
an important explanatory variable for the outcomes of a treeclimbing program. The participants for this experiment were notself-selected, making it possible to test whether variation in affinity for trees helps explain participants’ perceptions of treeclimbing programs and the extent of benefits derived from theprograms. We find that those participants who have a greateraffinity for trees will have a more favorable impression of treeclimbing programs, a greater desire to help forests and trees, andwillingness to try other new forest activities. It is possible thatthe tree-assisted therapy program produces better outcomes inpart because some of the extra elements included were designed
to increase affinity for trees.
The results presented here provide insight for designing community tree-climbing programs. This research also establishes
the merits of including purpose-specific therapeutic, educational,
and motivational elements in such programs.
©2008 International Society of Arboriculture

To our knowledge, this is the first study of the therapeutic andsocietal benefits of tree-climbing programs. The study builds on
previous studies on the benefits of tree-climbing and on related
work in forest therapy.
Our results indicate that positive health and well-being benefits from tree-climbing programs are achieved beyond those of
simply being in a forest. This is because our evaluations ofparticipants’ perceptions and mood states before and after the
program were conducted in the forest where the climbing took
place. Our results, then, indicate that tree-climbing activities inforests would increase the positive effects of forest therapy andsuggest that forest therapy and tree-climbing therapy may becomplementary.
Conversely, by focusing on trees rather than on the wholeforest, tree-climbing therapy is possible not only in forests, but inparks and other urban greenspaces. It provides an easily accessible activity that increases participants’ appreciation of trees
and their desire to help trees and forests.
The goal of this article is not to finalize a particular treeclimbing program, but to pioneer the investigation of how todesign tree-climbing programs to best serve specific needs andpurposes. In particular, the rehabilitative potential of treeclimbing activities for persons with disabilities or other special
needs would be a valuable avenue for future research.
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John Gathright (corresponding author)
Nagoya University
Tree Assisted Therapy
323-4 jyokoji cho seto 480 1201
Japan
info@johnsan.net
Yozo Yamada
Nagoya University
Bio Agricultural Science
323-4 jyokoji cho seto 480 1201
Japan
Miyako Morito
Nagoya University
Psychology
323-4 jyokoji cho seto 480 1201
Japan
Résumé. Cet article étudie comment le design planifié peut améliorer
les bénéfices sociaux et thérapeutiques à partir de programmes mettant
l’accent sur l’ascension récréative des arbres. Nous avons comparé unprogramme récréatif à un programme d’assistance-arbre thérapeutiqueen y incluant des objectifs spécifiques sous les aspects thérapeutiques,éducatifs et des éléments motivateurs. Nous avons découvert que leséléments additionnels qui sont inclus dans le programme d’assistancearbre thérapeutique sont efficaces pour accroître les bénéfices au niveau
des activités d’ascension d’arbres.
Zusammenfassung. Diese Studie untersucht, inwieweit ein Programm-Design die therapeutischen und sozialen Vorteile eines
Baumkletter-Kursangebot verbessern kann. Wir vergleichen ein Freizeitprogramm mit einem durch Bäume unterstützten Therapieprogramm,
welches zweckgebundene therapeutische, erzieherische und motivierende Elemente enthält. Wir fanden heraus, dass die zusätzlichen Elemente in dem baum-unterstützten Therapie-Programm sehr effektiv die
Vorteile der Kletteraktivität verstärken.
Resumen. Este reporte estudia el diseño de un programa para incrementar la terapéutica y beneficios sociales de programas encaminados ala actividad técnica de trepa a los árboles. Se diseñó una actividad
recreativa con un programa de trepa a los árboles que incluye específicos
propósitos terapéuticos, educativos y elementos de motivación. Se encontró que los elementos adicionales incluidos en el programa fueron
efectivos para mejorar los beneficios de la actividad de trepa a losárboles.

©2008 International Society of Arboriculture