Developing a Tree Care Program
Golf courses with good reputations for their tree plantings
realized long ago the value of a comprehensive program to care
for existing trees and properly plan for new tree plantings when
and where they become necessary. Those efforts have paid off
handsomely with balanced age classes of healthy, well-formed tree
species and a minimum of tree-related agronomic problems. This
article will examine strategies that can be used to develop the
foundation for a good tree maintenance program, and examine
specific pruning practices that can be used to maintain
healthier, more attractive trees and help rectify agronomic
There are several ways to develop a tree care program. Golf
courses that choose to complete the majority of work with their
own staff will employ a full-time arborist or tree specialist who
has both the knowledge and experience to help develop and
complete the practices. The extent of the work completed will
vary depending on experience, available equipment, and the amount
of liability the golf course is willing to assume. In many
instances the arborist/tree specialist will complete smaller
scale pruning, tree removal, and pest management work, and have
the larger spray operations, climbing/bucket work, and major tree
removals completed by outside contractors.
A large number of colleges and universities offer degree programs
in forest and shade tree management and arboriculture. Graduates
from such programs would be well suited for the position.
Students might also be available for summer placement jobs on the
golf course and eventually work into a full-time position as they
gain experience. The position requires overall knowledge of trees
and their specific requirements, including pruning, fertility,
irrigation, and pest management needs. Tree pruning and removal
skills are a must, as is the ability to properly identify and
evaluate hazardous trees.
This is not to say that a good tree maintenance program cannot be
developed without first hiring an experienced arborist. The golf
course superintendent may have the necessary background to
develop and oversee a relatively good program if he is fortunate
enough to possess the skills mentioned above and have the
necessary time. An even larger amount of the work would probably
be completed by outside contractors with a program organized in
A tree inventory is beneficial for any level of tree maintenance
completed on the golf course. You have to know the tree species,
its specific requirements, and the life expectancy in order to
plan and prioritize pruning work and other maintenance and
planting programs. This information is critical even if the
primary maintenance work is completed by outside contractors. The
inventory should identify tree species, map their locations,
estimate approximate age class and tree condition, provide site
characteristics, and any other pertinent notes. The tree's
estimated intrinsic and monetary values might also be included in
the inventory. Computer software, such as the Trims Tree
Management Program, can be helpful in producing the inventory.
Identifying the various tree species may be the most intimidating
hurdle in completing the inventory. The services of an arborist
or employee with training in tree identification are definitely
recommended, especially if a superintendent's dendrology
skills have faded. The inventory might serve as a good project
for a summer placement student with knowledge in tree
identification. There are also many good books and keys available
to aid in the identification process. University specialists,
extension agents, or local nursery personnel can also provide
assistance if the challenge is too great. Estimating monetary
values is more complex and should be left to an experienced
The tree plantings should be thoroughly inspected on an annual
basis to evaluate their condition and establish maintenance
priorities. The inspection would determine where tree pruning
work, individual tree removals, stand thinning, and new tree
plantings may be required. Fertility, pest management, and other
maintenance programs should be developed based on the results of
the evaluation. Information from the evaluation and tree
inventory, together with input from the superintendent, golf
professional, and green committee members should be used to
target sites where trees affect turf quality or negatively
Pruning work is a primary part of tree maintenance programs.
Unfortunately, the work is not fully utilized in many golf course
tree care programs. Pruning is used to enhance or modify a
tree's natural growth form. Remedial pruning is completed
regularly to remove diseased, damaged, poorly attached, or
crowded branches to improve a tree's structure and
appearance. Tree size can be maintained to a certain extent with
pruning. Pruning is also used to help train young trees. Pruning
can stimulate flowering in ornamental trees and vigor in stressed
or stagnated trees. Selective pruning is frequently completed on
golf courses to increase light penetration and air flow to the
tree and surrounding areas. Tree canopies are also raised from
the ground to gain more air movement and access below the tree.
Finally, root pruning is used to remove girdling roots from the
base of tree trunks and where tree roots are aggressively
competing with the turf.
The impact of the pruning work on the tree can be minimized by
properly positioning and completing the cut. The old standard
flush cut is no longer recommended except for adventitious water
sprouts or sucker branches. Branches should instead be cut along
the outside edge of branch bark ridge (shoulder rings) and collar
to minimize the wound's size and allow the tree to callus
over the cut more quickly. There are several techniques followed
to make a proper cut, depending on branch size. Smaller branches
are often cut with hand shears or hand saws, while large hand
saws or chain saws are used for larger cuts. Larger branches
require a series of cuts to prevent the bark and wood from
tearing and splitting back into the tree. The first cut is made
on the lower side of the branch, usually 1 to 2 feet from the
crotch. The cut is made upward about a quarter of the diameter or
until the saw begins to bind. The second cut is completed on top
of the branch and placed outside the first cut by 1 or 2 inches.
The second cut allows the branch to break cleanly off the tree.
The final cut is then made at the crotch, as recommended above.
Heavier branch stubs may need to be undercut and/or supported
during the final cut to avoid tearing the bark.
Applying wound dressing is no longer recommended. The dressings
may actually delay the process by which the tree recovers from
the wound. Paints are sometimes used to mask or improve a
wound's appearance, but those too will have no other
beneficial effects. Trees naturally isolate the wounds by
developing a chemical barrier in a process termed
compartmentalization. The barrier prevents most decay fungi and
bacteria from entering surrounding wood as the tree produces
callus tissue which in time will cover over the wound.
The timing of the pruning operations depends on the purpose of
the pruning work, the type of tree, and its condition. Minor or
light pruning work can be completed at any time of the year.
Dead, diseased, weak, or heavily shaded branches can also be
removed at any time with little negative effect on the tree.
Plant development will be affected least if the pruning work is
completed prior to the period of most rapid growth. The majority
of deciduous trees can therefore be pruned during, winter
dormancy and until spring growth resumes to correct structural
problems. Evergreen trees should be pruned just prior to spring
growth to minimize the chance of cold temperature injury around
the wounds. Trees such as maples, birch, and elm can bleed
heavily if pruned in early spring. The bleeding can be minimized
if pruning is completed in very late fall, early winter, or
mid-spring. Heavy bleeding can create unsightly stains and delay
the onset of callus tissue formation.
Reducing the tree's growth rate and size is accomplished most
effectively if pruning work is completed after the season's
growth flush has occurred. Pruning work should be scheduled in
spring to midsummer for this purpose. Keep this in mind when
thinning tree canopies to gain additional light and air flow.
Late summer and fall pruning work is least favorable, as larger
wounds recover more slowly and are more susceptible to the decay
fungi that sporulate in fall. Callusing is most rapid if pruning
work is completed prior to or soon after tree growth resumes in
spring. Use even more care when completing pruning cuts during
and immediately following the rapid spring growth period, as the
bark is particularly tender and is easily torn.
Nursery stock should have relatively good growth form. Do not
accept planting material if the structural branches are not
uniformly spaced, are too close together, or are poorly attached.
However, even good quality nursery stock will likely require some
pruning work as the trees mature to maintain good structure and
branching. Pruning should be minimal at the time the tree is
planted. Broken or damaged branches can be removed, as can
adventitious shoots. It is best to complete major pruning work
during the tree's early establishment period, as pruning
wounds are smaller and the work easier to complete. Large-scale
corrective pruning should be spread over several years to avoid
excessive stress on younger trees.
Training very young trees is a complex matter requiring knowledge
of the tree's growth form and function on the golf course.
Young trees should be inspected for uniformly spaced vertical and
radial branching and sound branch attachments along the main
leader. Remember, these young branches serve as the main scaffold
branches as the tree matures. Larger growing trees should have
wider spaced main or scaffold branching along the trunk for
optimum strength, while smaller growing trees should have more
closely spaced branching. The lateral branches should not be
larger than the trunk or main leader, as they compete for
dominance and result in a weak attachment. Horizontal branching
and wider angle branch attachments usually result in stronger
connections, which are more desirable.
Corrective pruning measures required for mature plantings
generally are more severe and costly to complete, especially if
the trees received little care in the past. Inspect the tree
canopy and specifically look at scaffold or main branching to
make sure the tree's canopy is well formed and in balance.
Poor quality branches, or those that are diseased, dead, or
interfering with each other should be removed. This process is
often referred to as dead wooding. Tree canopies that create
excessive shade, block air movement, affect play, or crowd each
other can be addressed through crown reduction or crown thinning.
Raising the crown is the term used for pruning work completed to
raise the tree canopy off the ground to increase light
penetration and air movement.
Dead wooding is especially important for older trees that contain
hazardous branching or decayed wood. Such wood should be removed,
along with any vines or foreign material. This type of pruning is
often completed prior to initiating crown thinning or reduction
work. Removing the weaker branches and dead wood makes it easier
to determine the additional pruning work required. Dead wooding
also is an excellent tool used to manage certain pests. However,
diseases such as fire blight and other canker-forming disorders
can be spread through pruning wounds, making it necessary to
disinfect pruning tools following each cut.
Crown thinning is completed to highlight a tree's branching
and to increase light penetration and air movement through the
canopy. Trees with overly dense canopies benefit from opening the
canopy. The additional light promotes stronger growth of the
remaining branches, encourages lateral branch development, and
increases branch tapering to make the tree less susceptible to
storm damage. Wind resistance can also be reduced by selective
thinning work. Crown thinning can result in the removal of a
third or more of the tree's canopy, which should not affect
vigorous deciduous trees. However, beech, birch, hornbeam,
eucalyptus, walnut, and most conifer trees are less tolerant of
severe pruning and therefore should have less of the canopy
removed at any one time.
Crown reduction is also a relatively common procedure used to
keep trees within size requirements. This type of pruning is
often used to overcome earlier mistakes in planting judgement.
Tree size can be controlled most effectively if pruning is
initiated before the tree reaches the desired size. Pruning cuts
will be smaller and the tree's appearance less affected.
Trees that require frequent crown reduction work probably should
be replaced, as their natural appearance will be altered. Crown
reduction also can be an effective means to address overcrowded
tree stands. The canopies of the smaller and less desirable trees
should be severely pruned, allowing the surrounding trees to
develop properly The pruned trees eventually will be removed as
the preferred trees develop.
Thinning-out, heading, and pollarding are pruning techniques used
in crown reduction. Thinning-out is the preferred technique when
the tree's natural growth form is to be maintained. It
involves pruning branches back to lower laterals (drop-crotching)
that are at least a third the diameter of the branch being
removed. Heading is used to drastically reduce canopy size. It
involves pruning the main branches back to stubs. This form of
pruning can leave very large wounds that may never callus, thus
providing sites for decay. It also results in very dense,
upright, and vigorous branching immediately below the cut. The
resulting branching is unnatural in appearance, poorly attached,
and generally not safe. It is not a recommended technique for
most situations. Pollarding is a type of heading operation used
in more formal landscape situations to keep larger growing trees
under size control. This technique is rarely used on golf
Raising the crown is often completed on conifer trees whose lower
branch whorls affect maintenance or play, or block sun and air
flow. This is completed by removing lower branches completely or
pruning them back to the next largest, up-right lateral branch to
reduce weight. Similar work is completed on deciduous trees
during the growing season when the branches are in full leaf.
This operation is often objectionable to many people, who dislike
the unnatural appearance it can create. It is possible to raise
the canopy height and still maintain a somewhat natural
appearance if the work is done carefully and extended over
Root pruning is another common practice on golf courses where
tree root competition reduces turf quality. Individual tree roots
may also have to be pruned manually if they begin to girdle the
tree. Tree roots are severed at a 12- to 20-inch depth using a
power trencher, vibratory plow, backhoe, or root cutting saw.
Standard recommendations are to provide 1 foot of distance
between the pruning trench and tree per inch of tree diameter at
chest height. Recent studies indicate, however, that pruning
along one side of moderately sized, healthy trees can be
completed at distances of 3 feet and closer without seriously
affecting the tree's growth rate or survival as long as the
remaining root system is intact and unrestricted. Larger and
slower growing trees might show more severe effects from such
close pruning. The study also demonstrated that the negative
effects of severe single- and multiple-side root pruning could be
reduced by thinning the tree's crown following the operation.
Pruning more than one side of a tree in a given year will cause
more stress and could leave the tree less stable.
Trees will continue to be a very important part of most golf
courses. Hopefully, this article has changed the way you look at
trees and tree care programs at your golf course. It is important
to remember that the passion reserved for trees does not have to
be devoted entirely to new planting programs. Institute a new
philosophy for trees that addresses maintenance needs equally
with new planting programs. Develop a tree inventory and, if
possible, add a tree specialist to your staff, or become more
familiar with trees yourself to better develop and implement
pruning and other maintenance programs. The existing trees will
definitely benefit, as will new plantings, which will be made
with more scrutiny Turf and trees can coexist nicely, especially
if we do not allow blind affection to get in the way of reality.
Harris, R. W. 1983.
Arboriculture Care of Trees, Shrubs, and Vines in the
Englewood Cliffs: Prentice Hall, Inc.
Harris, R. W.
Arboriculture: Integrated Management of Landscape Trees,
Shrubs, and Vines.
2nd ed., Regents/Prentice Hall, Englewood Cliffs, LCC#91-19477.
Miller, Jr., E D., and Neely, D. 1993.
The Effects of Trenching on Growth and Plant Health of
Selected Species of Shade Trees.
"J. Arboriculture" 19(4):226-229.
Sinclair, W. A., Lyon, H. H., and Johnson, W. T. 1987
Diseases of Trees and Shrubs.
Ithaca/London, Cornell University Press.
Tuffs, L. October, 1994.
Truce in the Trenches.
TREES are very important parts of most golf courses. Many golfers
will protect trees with a zeal matched only by their love for the
game itself. This blind affection for trees can result in poor
judgement or misguided priorities in tree planting and
maintenance programs. Proper planning and maintenance often
become secondary as the emphasis is placed on planting more and
more trees. This philosophy often leads to hasty decisions with
new plantings, resulting in poorly positioned trees that consist
of species that may not be well suited for the golf course or the
particular planting site. This can create immediate maintenance
headaches with the trees and will likely lead to future agronomic
problems with the turf. The lack of a good preventative
maintenance program also is apparent at such golf courses, as
many of the existing trees have structural problems or poor
growth form and appearance.