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Clark and Matheny: The Research Foundation to Tree Pruning
©2010 International Society of Arboriculture
110
The Research Foundation to Tree Pruning:
A Review of the Literature
Arboriculture & Urban Forestry 2010. 36(3): 110–120
James R. Clark and Nelda Matheny
Abstract. Two hundred one research publications including 152 journal articles were compiled. Forty-four journals were represent-
ed with the Journal of Arboriculture, Arboricultural & Urban Forestry, and Arboricultural Journal as the most frequently cited. Com-
partmentalization, wounding, wound response, decay development, and wound treatment were the most frequently noted topic areas.
The bibliography was organized in Zotero, an application using the Firefox web browser. Keywords were identi-
fied for each publication. Where either the article or its abstract was available, an annotation was created. This pa-
per describes the major topic areas identified in the review and discusses the future directions for pruning research.
Key Words: Tree Pruning; Literature Review.
Pruning is at the heart of arboriculture, one of the most impor-
tant services arborists provide. To paraphrase Alex Shigo (1989),
pruning can be one of the best things an arborist can do for a tree
and one of the worse things an arborist can do to a tree. Pruning
impacts both tree health and structure. It is practiced worldwide.
In 2007, the International Society of Arboriculture (ISA)
contracted HortScience, Inc. to prepare a literature review on
the topic of pruning. The focus of the review was the research
literature. The emphasis was on arboriculture but the review
could reference forestry and pomology literature as appropriate.
MATERIALS AND METHODS
In developing the review, the authors focused on peer-reviewed
sources, particularly scientific journals. The process was ini-
tiated by compiling references from standard industry refer-
ences such as Gilman’s Illustrated Guide to Pruning (2nd edi-
tion, 2002), and Arboriculture (Harris et al. 2004). The authors
also relied on O’Hara’s review of the forestry literature dealing
with pruning and wounding (2007). The online archive of the
Journal of Arboriculture and Arboriculture & Urban Forestry
were searched for titles containing the word “pruning.” There
were 42 citations, some of which appeared prior to 1990—a
period when articles in the Journal of Arboriculture were not
necessarily research based. Major industry standards used in
the U.S. (ANSI 2008) and Europe (British Standards Institute
1989; ZTV-Baumpflege 2001; European Arboricultural Council
2008) were then reviewed as well as their supporting publica-
tions (Gilman and Lilly 2002; Kempter 2004; Lonsdale 2008).
ISA specifically requested an effort to access literature from
non-English sources. Literature from outside North America
was queried in several ways. First, two English-language jour-
nals published in Europe, the Arboricultural Journal (Arbo-
ricultural Association, UK) and Urban Forestry and Urban
Greening (Springer) were reviewed. This approach yielded
good results with Schwarze et al. (2007) and Dujeseifken
(2002) as examples. Second, links to non-English publica-
tions were searched. Finally, a draft of the literature review
was sent to scientists in Germany, Denmark, Italy, and France
for comment. Additional references were then incorporated.
There were limitations to this approach. First, journals
published in languages other than English were generally in-
accessible. Second, papers where pruning was not a key-
word may have been missed. Third, journals with limited ex-
posure and nonpublished dissertations were likely omitted.
Fourth, no commercial or university databases were used.
Zotero (www.zotero.org) was selected as the bibliographic
management program. The program links to Firefox’s Mozilla
web browser. For each citation, keywords (called “tags” in Zote-
ro’s lexicon) were identified. In addition, an annotation (“note” in
Zotero) was prepared (Table 1). The breadth of both keywords and
annotation was limited by access to the complete paper. Journal of
Arboriculture and Arboriculture & Urban Forestry were unique
in that the online archive was completely accessible to members
of the International Society of Arboriculture. Older issues can be
accessed without membership. Most journals, however, were not
fully accessible. In almost all cases, abstracts were used. Approxi-
mately 75% of the citations had access to the full article. In the re-
maining 25%, annotations were either very limited or not entered.
DESCRIPTION OF THE CITATIONS
Two hundred one citations were assembled. Among this group
were 20 books and 10 book sections. These had broad focus and
were included to identify general resources. For the professional
arborist, Gilman (2002) is likely to be the best reference as it
covers all aspects of the topic from young trees to mature speci-
mens, in a variety of settings. The book is also well-illustrated.
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Arboriculture & Urban Forestry 36(3): May 2010
©2010 International Society of Arboriculture
111
Forest tree pruning was represented by Mayer Wegelin’s papers
(1936; 1952), the silvicultural textbook of Smith et al. (1996), and
a Hanley et al. (1995) volume on pruning of conifers. Also refer-
enced were resources written in German (Hoster 1993; Dujesiefken
1995; Pfisterer 1999; Stobbe et al. 2002a; Stobbe et al. 2002b),
and French (Drenou 1999; Austad and Hauge 2007). Palms were
referenced through Broschat and Meerow (2000). For the most
part, books were included as general references to the topic of
pruning but lacked extensive references to the scientific literature.
Journal articles comprised 152 of the 201 citations. For-
ty-four journals were referenced, published in 12 countries
(Table 2). Journal of Arboriculture (51), Arboriculture & Ur-
ban Forestry (12), and Arboricultural Journal (9) were the
most frequently referenced. Journals cited originated in Eu-
rope (25), North America (17), and the Asia-Pacific region (2).
More than half of the journals (24) were focused on for-
estry and forest science. Another 10, such as American Jour-
nal of Botany, were oriented to the traditional plant scienc-
es. Three journals were horticultural in focus; another five
were oriented to arboricultural and urban forestry. Two jour-
nals, Trees—Structure and Function and Tree Physiology,
crossed lines among forestry, arboriculture, and horticulture.
Citations arose primarily from English language journals
(113 of 201). Some journals, notably Arboriculture & Urban
Forestry, Arboricultural Journal, Canadian Journal of Botany,
Canadian Journal of Forest Research, and Journal of Arbori-
culture may provide abstracts in languages other than English.
Also included were citations in French, German, and Italian.
A small fraction of the citations had not undergone the nor-
mal peer-review process. Four citations were reports of the
USDA Forest Service, all authored by Shigo (Shigo and Lar-
son 1969; Shigo and Marx 1977; Shigo at al. 1979; Butin and
Shigo 1981). Such reports are normally reviewed by other sci-
entists within the agency. Articles in Arborist News, such as
Fraedrich and Smiley (1996) and Guggenmoos (2007), receive
technical review. The nature of the review for books, industry
standards, extension publications, conference proceedings, and
book sections was unknown. The main reason for including ma-
terial that had not been peer-reviewed was to highlight a specific
pruning topic. This will be discussed in the following section.
A list of all authors was compiled. The most frequently cited au-
thors were Alex Shigo of the United States and Dirk Dujesiefsken of
Germany. Both were noted 13 times. Authors cited with four or more
references included Ed Gilman, Jason Grabosky, Brian Kane, Dan
Neely, and Tom Smiley of the United States; Karen Barry and Eliza-
beth Pinkard of Australia; W. Liese, D. Eckstein, Francis Schwarze,
and Horst Stobbe, of Germany; and Francesco Ferrini of Italy.
MAJOR TOPICS IN PRUNING RESEARCH
Research topics were identified by the frequency with which
keywords were applied. The following discussion high-
lights a portion of the literature included in the bibliography.
The dominant theme of the literature review was wound-
ing, the tree’s response and possible treatments to affect that
response. Wounding and the tree response, to it were to-
gether noted as keywords in 30 of the 201 citations. They
were often linked to compartmentalization (24 citations), de-
cay (25), and wound dressing (10). O’Hara (2007) provided
a review of the literature on this topic, emphasizing wound
response and the goal of producing clear wood in timber.
Modern research activity in this area might begin with Shigo and
Larson’s (1969) photographic summary of the patterns of discolor-
ation and decay in hardwoods of the northeastern U.S. This report
focused on the relationship of external appearance to wood quality.
It was observational in nature, rather than founded in experimen-
tation. One finding was that covering pruning wounds with “dress-
ings” neither improved closure nor reduced the presence of decay.
In 1977, Shigo and Marx released their seminal report Com-
partmentalization of decay in trees, which introduced the CODIT
concept. Shigo et al. (1979) then reported on the relationship of
flush cuts to the development of internal decay and other defects
in black walnut (Juglans nigra). The authors noted, “When prun-
ing is done late in the life of a tree, care must be taken not to
remove the branch collars that form about the bases of dead and
dying branches.” Also in 1979, Shortle expanded on the compart-
mentalization model with very well-illustrated paper. He posed
the “heartrot” concept, describing how external wounds allow
decay fungi to enter and become established in the tree. Devel-
opment of the CODIT model culminated with two publications:
How tree branches are attached to trunks (Shigo 1985) and Com-
partmentalization: A conceptual framework for understanding
how trees grow and defend themselves (Shigo 1984). As noted
previously, the vast bulk of this work was observational in nature.
Shigo was neither the only scientist interested in tree re-
sponse to wounding nor the first to examine it. For example,
foresters have long had an interest in tree response to pruning
and wounding (McQuilkin 1950; Herring et al. 1958; O’Hara
2007). Von Aufsess (1975) noted the formation of a protective
zone at the base of branches. Neely (1970; 1979) observed that
production of callus (i.e., woundwood) at the margins of prun-
ing wounds was related to tree vigor, as measured by growth.
Research on the topic of tree wound response and its man-
agement continued through the following decades. Experiments
Table 1. Examples of annotations included in the literature
review.
Gilman, E.F., and G. Knox. 2005. Pruning type affects decay and structure
of crapemyrtle. Journal of Arboriculture 31:38–47.
Established Lagerstroemia × Natchez trees were topped, pollarded
or unpruned for four years. Topping resulted in more dead stubs and
discolored wood than pollarding which had limited decay development.
Recommended developing pollards rather than routine topping. Nice
photos. Florida US.
Neilsen, W., and E. Pinkard. 2003. Effects of green pruning on growth Pinus
radiata. Canadian Journal of Forest Research. 33:2067–2073.
Crowns of 6- to 8-year-old, plantation Monterey pine were raised. Rais-
ing to 45% of tree height had no effect on growth which was reduced
with greater crown removal. Suggests maintaining a live crown ratio of
55%. Tasmania Australia.
Schwarze, F., J. Gruner, M. Schubert, and S. Fink. 2007. Defence reactions
and fungal colonization in Fraxinus excelsior and Tilia platyphyllos after
stem wounding. Arboricultural Journal 30:61–82.
Describes the anatomy of the barrier zone (= CODIT wall 4), suggesting
that differences in this zone account in part for species differences in de-
cay resistance. Strong within species variation in discoloration associated
with both increment borer holes and chain saw cuts to the stem. Also
isolated fungi from around the wounds. Excellent photos. Good discus-
sion of fungal development and tree response. Freiburg Germany.
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Clark and Matheny: The Research Foundation to Tree Pruning
©2010 International Society of Arboriculture
112
focusing on application of wound dressings generally found ma-
terials to be ineffective. There has been excellent work study-
ing the development of reaction and barrier zones in response
to wounding of all types. Dujesiefken et al. (1999), Barry et
al. (2000), Pearce (2000), Schwarze (2001), and Schwarze
et al. (2007) provide detailed, very well-illustrated analyses.
The question of whether to employ flush or natural tar-
get (i.e., collar) cuts has generally sided with the latter (De-
florio et al. 2007). O’Hara (2007) suggested that one type or
style of cut may not meet all management needs. Researchers
tend to agree that smaller pruning wounds are preferable to
larger ones, and pruning is most appropriate on young trees.
Research in the area of wound response has also involved ex-
aminations of branch structure and strength. Eisner et al. (2002b)
characterized the relative size of branch to stem as aspect ratio
and used this measure to assess response to pruning. Removal of
branches with aspect ratios greater than 0.39 in red maple (Acer
rubrum) and 0.59 in southern live oak (Quercus virginiana)
resulted in greater discoloration in the parent. Branches with a
more vertical orientation were more likely to have pith continuous
with the stem. Removal of limbs with this pith connection resulted
in more discoloration in the parent stem. Gilman
and Grabosky (2006) observed that as aspect ratio
increased, the amount of discoloration and decay
also increased. Another key finding was the obser-
vation that pruning can slow down the growth of
a codominant stem to the extent that a branch pro-
tection zone forms. Another facet of branch struc-
ture research has been the documentation that as
aspect ratio increases, strength decreases (Gil-
man 2003; Kane 2007; Kane and Farrell 2008).
At the current time, the Hamburg Tree Prun-
ing System (Dujesiefken and Stobbe 2002;
Dujesiefken et al. 2005a) may best represent
the evolution of research into wound response.
It is based on observations of 750 wounds on
115 mature street and park trees. The system is
based on the natural target pruning approach
and has been integrated into German standards.
Another important topic encountered in the
review was pruning around overhead utility
lines (16 citations). The topic first appeared in
the Journal of Arboriculture in conference pa-
pers during the 1980s (Holewinski 1983; John-
stone 1983). Both raised ideas of using what has
become known as either natural or directional
pruning rather than traditional roundover trim-
ming. Goodfellow et al. (1987) demonstrated
that directional pruning resulted in less regrowth
than roundover. Johnstone (1988) followed with
a description of how directional pruning could
be successfully integrated into a utility’s vegeta-
tion management program. Directional pruning
certainly came of age with the publication of
Pruning trees near electrical utility lines (1990),
also known as Shigo’s “yellow book.” Although
it was not a research-based publication, the yel-
low book became a key element of utility prac-
tice. It has largely been superseded by Kempter’s
(2004) summary of best management practices.
In recent years, research in the utility side
of arboriculture has focused on three areas: 1) service reliabil-
ity (Galvin 2005; Guggenmoos 2007), 2) impacts of pruning on
tree structure and stability (Browning and Wiant 1997; Dahle
2006a; Dahle 2006b), and 3) the response of property owners
to changes in practice (Close 2001; Kuhns and Reiter 2007).
Outside of the U.S., there has been essentially no research in
the utility arboriculture area, at least that which has been pub-
lished in English language journals. One exception was Millet and
Bouchard’s (2003) application of the French architectural analy-
sis methods to the utility setting. They suggested species architec-
tural patterns should be considered in making pruning decisions.
Municipal arborists have benefited from research deal-
ing with pruning of street trees (10 citations). In 1981, Miller
and Sylvester addressed the question: What is the appropriate
length of the pruning cycle for municipal trees? Using Milwau-
kee, WI, as a test case, they concluded four to five years was
the appropriate pruning cycle. They observed that tree condi-
tion declined as the length of the pruning cycle increased. Tous-
saint et al. (2002) provided a somewhat similar assessment for
European linden (Tilia × europaea) street trees in France. They
Table 2. Journals referenced in the pruning bibliography.
Journal Origin No. of Citations
Acer Italy 7
Agroforestry Systems Netherlands 1
Allgemeine Forstzeitschrift Germany 1
American Journal of Botany United States 1
Annals of Applied Biology United Kingdom 3
Annals of Botany United Kingdom 1
Annual Review of Phytopathology United States 1
Arboricultural Journal United Kingdom 9
Arboriculture & Urban Forestry United States 12
Biological Conservation United Kingdom 1
Biotechnology Agronomy Society & Environment Belgium 1
Canadian Journal of Botany Canada 1
Canadian Journal of Forest Research Canada 7
European Journal of Forest Pathology Netherlands 1
European Journal of Forest Research Germany 1
Forest Ecology and Management United States 5
Forest Pathology United States 1
Forest Science United States 1
Forestry United Kingdom 1
Forst und Holz Germany 1
Forstwissenschaftliches Centralblatt Germany 3
Holz als Roh- und Werkstoff Germany 1
Holzforschung Germany 2
HortScience United States 3
International Association Wood Anatomy Bulletin United States 1
Journal of American Society Horticultural Science United States 2
Journal Applied Ecology United Kingdom 1
Journal of Arboriculture United States 51
Journal of Forestry United States 5
Journal of Wood Science United States 1
Neue Landschaft Germany 1
New Forests United Kingdom 1
New Phytologist United Kingdom 1
New Zealand Tree Grower New Zealand 1
Phytopathology United States 1
Proc. American Society of Horticultural Science United States 1
Schweizerische Zeitschrift fur Forstwese Germany 1
Sherwood Italy 4
Silva Fennica Finland 2
Tasforests Australia 1
Tree Physiology United Kingdom 1
Trees - Structure & Function Germany 4
Urban Forestry & Urban Greening Denmark 5
Western Journal Applied Forestry United States 1
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contrasted the costs of routine pruning to those associated with
topping, finding the former both less expensive and less dam-
aging in the long-term. Campanella et al. (2009) followed this
with an assessment of the long-term costs of roundover, resto-
ration, and thinning of European linden street trees in Belgium.
Nowak (1990) evaluated the results of street tree inventories
from 11 tree species in the U.S. He observed strong species-
specific results in pruning requirements, suggesting that prun-
ing cycle may be species-specific. American elm (Ulmus amer-
icana) and boxelder (Acer negundo) had the most urgent need
for pruning, with London plane (Platanus × acerifolia) and
honeylocust (Gleditsia triacanthos f. inermis) the least urgent.
Ehsen (1987) described street tree pruning in Germany
with a focus on how pruning needs change over the tree’s
life-span, moving from a focus on training in young trees to
maintenance (e.g., cleaning and raising) on mature trees to
reduction in overmature trees. Balder et al. (1997) summa-
rized street tree selection and management in Germany, using
Berlin as an example. Mascelli et al. (2008) used street trees
in Prato, Italy, as a case study of pruning and management.
The research foundation for the range of types or styles of
pruning varies widely. In some areas, research is only now catch-
ing up with long-time practice. In others, research provided clear
direction to practice. Where to make cuts and the need to use
wound dressings is but one example. The methods for, and value
of, pruning young trees to develop good structure has been well-
documented whether pruning involves retaining low branches
(Leiser et al. 1972), or selective bud removal (Oleksak et al. 1997).
In contrast, other pruning practices have less well-devel-
oped foundation. There is no research to suggest crown thin-
ning improves either tree health or structural stability. And,
while it has been common practice for many years, reduc-
tion pruning to a branch at least one-third the diameter of
the stem lacked a scientific basis. It was not until Grabosky
and Gilman (2007) evaluated reduction cuts on two ma-
ture oak species that a tentative basis could be established.
The architectural style of pruning is common in France
(Stefulesco 1995; Drenou 1999; Drenou 2000). In many
ways, research has followed practice, as this pruning tech-
nique is quite old. Timing and techniques of architectural
pruning have been elucidated by the research of scien-
tists such as Bory et al. (1996) and Clair-Maczulajtys et al.
(1999) who have focused on carbohydrate storage patterns
in trees. Pollards are also a common feature of the Euro-
pean landscape. Both Austad and Hauge (2007) and Fer-
rini (2006c) discuss their physiology and management.
Much of the work with crown-raising has occurred in for-
estry, where the objective is to have the lower trunk free of
branches. From Slabaugh (1957) to Neilsen and Pinkard
(2003), research has documented that removal of up to
50% of the live crown of young trees by lifting does not ad-
versely impact growth. In summarizing the results from
8 field studies with Douglas-fir (Pseudotsuga menziesii),
O’Hara (1991) suggested 33% crown removal as the limit.
Pruning is considered one of the important tools in the prac-
tice of plant health care. Svihra (1994) summarized the litera-
ture regarding eradicative pruning (i.e., the removal of infested
and infected branches). Pruning has been used to manage dis-
ease problems such as Dutch elm disease (Gregory and Al-
lison 1979) and oak wilt (Appel 1994; Camilli et al. 2007). It
is also important in the management of bronze birch borer
(Ball 1992) and bark beetles (Barger and Cannon 1987). One
of the key results of such work is the knowledge that many
insects are attracted to fresh pruning wounds. For this rea-
son, pruning should take place when insects are not active.
Arborists have long believed that proper pruning reduced
the likelihood of damage during storms. Duryea et al. (1996)
documented the effects of Hurricane Andrew in Florida, sup-
ported this observation for some species. Luley et al. (2002)
documented branch failures in sweetgum (Liquidambar
styraciflua) trees in Rochester, NY, over an eight-year period.
Pruning did not reduce the number of failures (most of which
occurred while the tree was in leaf), but did result in fewer
service requests. Kane (2008) examined the pattern of tree
failure following a severe windstorm in Massachusetts find-
ing that pre-storm pruning “had little effect on (tree) failure.”
Pruning has been used as a tool in evaluating tree response to
wind, particularly related to the affect on trunk movement. Smiley
and Kane (2006), Pavlis et al. (2008), and Gilman et al. (2008a;
2008b) simulated wind conditions to evaluate trunk movement
of young trees in response to crown thinning, raising and reduc-
tion pruning. Both crown reduction and crown thinning reduced
trunk movement (Gilman et al. 2008a; Gilman et al. 2008b) and
wind load (Smiley and Kane 2006). Essentially, the more crown
mass removed, the lower the trunk movement or wind load.
Gilman et al. (2008a) noted the response was a complex one,
and the authors cautioned against extrapolating to larger trees.
Moore and Maguire (2005) examined the effects of crown-
raising on movement of 14 m to 20 m Douglas-fir trees. Nat-
ural sway frequency increased as pruning level increased,
although this was not noticeable until 80% of the canopy
had been removed. Changes in sway frequency were related
to how crown mass was distributed. They noted that treat-
ing branches as a lumped mass may not be appropriate.
Standards for pruning are found in the U.S. (ANSI 2008), the
United Kingdom (British Standards Institute 1989), and Germa-
ny (ZTV-Baumpflege 2001). In each case, the standard provides
a common vocabulary and procedures for pruning activities. In
the U.S., the International Society of Arboriculture (Gilman and
Lilly 2002; Kempter 2004) produced a companion volume to the
standard, aimed at defining best practice. In a somewhat similar
manner, the European Arboricultural Council (2008) recently up-
dated the European Tree Pruning Guide. In Italy, the concept of
industry standards remains under discussion (see di Lobis 2003).
RESEARCH TOPICS FOR THE FUTURE
Arboricultural practice should have a foundation in research.
In the area of pruning, a foundation is present to some extent.
It seems clear that employing removal and reduction cuts has
been documented by experimentation and careful observa-
tion. Research by Shigo and more recently by Dujesiefken
has supported use of the branch collar, natural target ap-
proach to selecting the location of a removal cut. Although
less well-defined, the same is true for reduction pruning, pri-
marily through work of Ed Gilman and Jason Grabosky.
In utility arboriculture, reduction cuts take the form of di-
rectional pruning—the effort to use a tree’s natural growth
pattern to aid in maintaining clearance. The literature docu-
ments the value of directional pruning and the problems as-
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Clark and Matheny: The Research Foundation to Tree Pruning
©2010 International Society of Arboriculture
114
sociated with topping and traditional roundover trimming.
Future research could further validate the few experiments
in this area. In addition, research along the line of Millet and
Bouchard’s (2003) application of architectural analysis to
line clearance would enhance the idea of directional growth.
Additional research is needed to support the use of pruning
in the area of plant health care. Although effectiveness of sanita-
tion or eradicative pruning has been documented, use of cleaning
and thinning to improve overall plant health has not. In a similar
manner, an answer to the question, “Does pruning reduce the po-
tential for windthrow, windsnap, or failure during storms?” has
not yet been developed. Most recent research has been with rela-
tively small trees rather than mature individuals. A recent article
by Kane and Harris (2008) reviews the research on this topic.
Access to non-English language journals and those in fields
such as forestry is ever-increasing but is not without its limitations.
First, many but not all journals have some online presence. Ab-
stracts can generally be accessed free of charge. Articles, however,
must be purchased. A second limitation to a broader application
of the world-wide literature is the lack of a common vocabulary.
Is early pruning the same as formative pruning? Is forestry’s green
pruning equivalent to crown raising? Comparison of professional
standards will reduce confusion about terms. A third limitation is
language, as only few journals provide abstracts in other languag-
es. Fewer still offer table and figure captions in a second language.
Acknowledgments. The authors very much appreciate the comments
and suggestions of two anonymous reviewers as well as those of the
editor. We acknowledge the encouragement and support of the ISA Sci-
ence and Research Committee, particularly Greg McPherson and Sharon
Lilly. Thanks to the Department of Plant Biology, University of Califor-
nia (Davis) for providing access to the campus library.
LITERATURE CITED
Harris, R., J. Clark and N. Matheny. 2004. Arboriculture—Integrated
management of landscape trees shrubs and vines. 4th edition. Pren-
tice Hall. Upper Saddle River NJ.
Kane, B., and R. Harris. 2008. Does pruning reduce the risk of tree fail-
ure? Arborist News 17:46-48.
Shigo, A. 1989. Tree Pruning—A worldwide photo guide. Shigo and
Trees Associates. Durham NH.
James R. Clark (corresponding author)
HortScience, Inc.
P.O. Box 754
Pleasanton CA 94566, U.S.
jim@hortscience.com
Nelda Matheny
HortScience, Inc.
P.O. Box 754
Pleasanton CA 94566, U.S.
Résumé. Deux cents une publications de recherches, incluant 152
articles de journaux, ont été compilés. Quarante-quatre journaux étaient
représentés, et le Journal of Arboriculture, le Arboricultural & Urban
Forestry ainsi que le Arboricultural Journal étaient les plus fréquemment
cités. La compartimentation, les blessures, la réaction aux blessures, le
développement de la carie et le traitement des blessures étaient les sujets
les plus fréquemment traités.
La bibliographie a été montée sur Zotero, une application faisant ap-
pel au navigateur Firefox. Les mots-clés ont été identifiés pour chacune
des publications. Lorsque l’article ou le résumé était disponible, une an-
notation a été inscrite. Cet article décrit les sujets majeurs traités qui ont
été identifiés dans cette revue et présente une discussion des directions
futures en ce qui regarde l’élagage.
Zusammenfassung. 201 Forschungspublikationen, einschließlich
152 Journalartikel wurden zusammengestellt. 44 Journale, einschließlich
Journal of Arboriculture, Arboricultural & Urban Forestry, und Arbori-
cultural Journal als die meist zitierten, wurden präsentiert. Kompartmen-
talisierung, Verletzung, Wundreaktion, Fäuleentwicklung und Wundbe-
handlung waren die häufigsten Themen.
Die Bibliographie wurde in Zotero organisiert, eine Applikation
von dem Browser Firefox, welcher die Schlüsselworte in jeder Publika-
tion identifiziert. Wo entweder der Artikel oder sein Abstrakt erhältlich
war, wurde ein Vermerk gemacht. Diese Studie beschreibt die Haupt-
themengebiete, die in der Durchsicht identifiziert wurden und diskutiert
die zukünftigen Richtungen für die Baumpflege.
Resumen. Se compilaron 201 publicaciones de investigaciones in-
cluyendo 152 artículos de journal. Cuarenta y cuatro jornals estuvieron
representados por el Journal of Arboriculture, Arboricultural & Urban
Forestry, y Arboricultural Journal como los más frecuentemente cita-
dos. Compartimentación, herida, respuesta a la herida, desarrollo de la
descomposición y tratamiento de heridas fueron los tópicos más fre-
cuentes. La bibliografía estuvo organizada en Zotero, una aplicación que
usa el navegador Firefox. Se identificaron palabras claves para cada pub-
licación. Cuando el artículo o su abstract estuvieron disponibles, se creó
una anotación. Este trabajo describe los tópicos principales identificados
en la revisión y discute las direcciones futuras para la investigación sobre
la poda.
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