The trees of our urban forests
provide shelter, purify the air we breathe, increase property
values, conserve energy, and enhance quality of life in our cities.
Trees inspire strong emotional reactions in the people who live,
work and recreate under their branches. Strong emotions coupled
with competing interests often result in a trip to the lawyer's
office. Sooner or later one of your clients will have a legal
dilemma involving a tree. The purpose of this article is to provide
you with a framework to analyze the problem.
Nuisance Trees: Encroaching
Branches or Roots
The primary legal questions involve issues of nuisance, negligence,
and trespass. But the analysis starts by identifying: Whose
tree is it?
In general, the location of the tree trunk determines who owns
the tree. A tree that stands solely on your client's property
belongs to your client. Disputes arise when trees straddle a
boundary line or when the branches of your client's tree encroach
onto the neighbor's property. Jurisdictions differ on boundary
trees. In some states, trees standing along a boundary line are
the common property of the neighbors on either side of the boundary,
and neither neighbor can remove the tree without the consent
of the other. This includes the tree that starts out in one yard
and grows into the boundary of the neighbor's yard.
In Minnesota, the mere presence of a tree trunk on the boundary
line does not create a boundary tree or determine ownership.
Instead, the court looks at the intention of the neighboring
property owners. A tree is a boundary tree if it was planted
jointly or treated as common property by agreement, acquiescence,
or course of conduct.1 For example, adjoining
owners who split the costs of pruning and maintaining a boundary
tree or hedge would probably be considered co-owners of the tree
or hedge. So, when a broken limb or a tree disease becomes a
problem, the co-owners share responsibility for fixing the problem.
Branches that overhang your client's property or tree roots
that push up a sidewalk or clog a sewer are considered a nuisance.
"Anything which is injurious to health, or indecent or offensive
to the senses, or an obstruction to the free use of property,
so as to interfere with the comfortable enjoyment of life or
property, is a nuisance."2
The leading Minnesota case on nuisance trees is Holmberg v.
Bergin.3 In that case, a Minneapolis
homeowner planted an elm tree within 15 inches of the property
line. Over the course of 26 years, the tree grew to be 30 inches
in diameter and 75 feet high. The trunk grew across the boundary
line, pushing the fence out of alignment. The roots extended
into the neighbors' yard and caused the sidewalk to tip toward
the house, resulting in a drainage problem in the neighbors'
basement. The Holmberg court found that the tree was not
a co-owned boundary tree but was a nuisance, because the tree
roots obstructed the neighbors' free use and enjoyment of their
property. The neighbors sued for monetary damages and an injunction
to prune the roots or remove the tree. Experts for both sides
acknowledged that corrective action to restore the grade would
damage the roots and either kill the tree or make it dangerously
unstable. The court ordered the tree cut down, because the alternative
-- severe root pruning -- would have weakened the tree or caused
the tree to die, endangering the neighbor's home if the tree
blew over in a windstorm. The court disallowed money damages,
because the neighbors had failed to take advantage of earlier
opportunities to exercise self-help and remove the invading roots.
Using Self-Help. Property owners in every state
have the right to use self-help to prune branches or roots of
a neighbor's tree that encroach onto their property. Some states
follow the Massachusetts Rule, where self-help is the exclusive
remedy for encroaching branches or roots.4
Self-help is an alternative to going to court.
The rationale is that self-help prevents the wasteful, needless
use of the judicial system and vexatious lawsuits.5
It's a tradeoff: your client fixes her problem at her own expense,
instead of slogging through the expense and uncertainty of the
Minnesota courts do not follow the Massachusetts Rule. In Minnesota,
self-help is encouraged, with discretion, but it is not the exclusive
remedy. Equitable remedies to abate the nuisance are available.
"The law is clear that one cannot exercise his right to
plant a tree in such a manner as to invade the rights of adjoining
landowners. When one brings a foreign substance on his land,
he must not permit it to injure his neighbor."6
When self-help is not practical or reasonable, your client can
go to court for an injunction or other equitable remedies to
have the nuisance abated.
Your client's guidelines for self-help include:
- Prune only up to the boundary line -- at your client's own
- Don't trespass. Get permission to enter onto the neighbor's
property to do the pruning, unless the encroaching branches or
roots threaten to cause imminent harm to your client's property.
- Don't cut down a tree whose trunk is located on the neighbor's
property, even if the branches stray onto your client's property.
- Maintain, don't destroy. Don't jeopardize the health of the
tree or cause foreseeable injury. For example, pruning an oak
tree from April through September could make the tree vulnerable
to oak wilt, a virulent disease. Or pruning a tree's roots could
destabilize the tree and cause it to topple over.
- Advise your client to seek the opinion of a certified arborist,
a specialist in the care of individual trees, about the tree's
condition. Look in the Yellow Pages under "tree service,"
and look for the arborist's membership in professional organizations,
such as the Minnesota Society of Arboriculture (MSA), the International
Society of Arboriculture (ISA), or the National Arborist Association
The trend in tree law is toward the California Rule or "self-help
nice." Minnesota courts have not expressly adopted the California
Rule, but it appears to be a natural outgrowth of Holmgren
v. Bergin, supra. In appropriate circumstances, a neighbor
who is being injured by a nuisance may protect himself by unilaterally
abating the nuisance. However, the abater must act in a reasonable
manner at reasonable time, and must avoid causing foreseeable
injury to the tree. A showing of malice on the part of the abater
evidences a strong indication that the self-help was unreasonable.7
Leaves Happen. Another area of contention is
tree debris: leaves, acorns, fallen fruit, branches, sap. There
is not a Minnesota case directly on point. However, other jurisdictions
have recognized that the natural growth of trees includes shade,
invading roots, leaves, and overhanging boughs,8
and that liability is reasonable when there is "sensible
damage,"9 such as a damaged roof,
not mere debris from a healthy tree. Your client, who is sick
and tired of sweeping the apple blossoms off his driveway after
they have fallen from his neighbor's tree, probably has no cause
of action. Going to court to have the neighbor ordered to pick
up fallen debris is not practical or economical, and is probably
why there is not much precedent on this issue.
Fruit of the Neighbor's Tree. Neighbors may
disagree as to who has the right to the apples or other fruit
growing on an encroaching tree branch. The rule of thumb is that
if the tree trunk stands in a neighbor's yard, all of the fruit
wherever it is hanging belongs to the neighbor.10
Picking the fruit may not be so simple. Ownership of the fruit
does not give the neighbor any right to trespass onto your client's
property to retrieve the fruit. Courts would probably weigh the
right to keep trespassers out of your client's yard against the
tree owner's right to harvest the fruit of her tree. The orchard
owner whose livelihood depends upon the harvest probably has
a stronger claim than an urban gardener.
Trees and Limbs
The law is also unclear on the issue of fallen fruit. As a practical
matter, it would not be worthwhile for a neighbor to sue your
client for keeping fallen fruit, because it would have nominal
value. The courts would probably hold the tree owner responsible
for making advance arrangements to harvest the fruit if it had
sufficient value to bother with. Your client is probably safe
to keep the fallen fruit if his neighbor says nothing about it.
As with most neighbor disputes, the best counsel you can give
is to encourage communication and neighborliness.
The trend across the country is to hold tree owners legally
responsible for damage caused by unsound or "hazard trees."11 A hazard tree is a tree with a defect plus
a target, such as a sidewalk, a car, or a house in the path of
an unstable or decaying tree.
Minnesota cases involving negligence in tree law tend to fall
into two categories: damage caused by trees or damage
done to trees. Foreseeability is the common thread that
runs through both types of claims. In both instances, courts
will look at what should have been obvious to the tree owner
about the tree's condition.
Damage Your Client's Tree Causes. If a neighbor's
tree is unsound and threatens your client's property, the neighbor
may be liable for any damage that occurs. The test is whether
the tree owner knew or should have known that damage was likely.
A tree owner is not expected to be a tree expert, but she is
expected to recognize obvious symptoms of a problem, such as
the unseasonal lack of leaves, a dead limb, visible decay, or
a tree leaning dangerously to one side. If the potential for
damage is foreseeable and if the tree owner fails to take corrective
action, the courts will likely hold the owner legally responsible
for damage caused to people or property.
In an unpublished opinion, the Minnesota Court of Appeals found
that a landowner was not liable in a personal injury case where
the landowner's tree did not pose an obvious danger.12
In that case, a tree trimmer was injured when a decaying branch
broke. Liability was not imposed, because the branch appeared
to be sturdy and showed no signs of decay. In another case, a
landowner was found to owe no duty to protect a pedestrian from
a low-hanging branch that was clearly visible.13
What's Entropy Got to Do With It? A Georgia
case that reaches the same conclusion about foreseeable danger
is worth quoting. Taking judicial notice of the Second Law of
Thermodynamics, the court said,
This law tells us that all in the universe, trees, human beings,
plants, animals, buildings, and all else are headed downward
from complexity to simplicity toward decay, deterioration, decadence,
and death. Everything heads towards decay; for example, a tree
decaying, which is an increase of entropy, or uselessness. We
are specifically limiting liability to patent, visible decay,
and not the normal, usual, latent, micro-nonvisible, accumulative
decay. In other words, there is no duty to consistently and constantly
check all pine trees for non-visible rot, as the manifestation
of decay must be visible, apparent, and patent so that one could
be aware that high winds might combine with visible rot and cause
Damage Done TO Trees. In a leading Minnesota
case on negligent damage to trees arose when a church hired a
road contractor to expand a parking area. The contractor piled
soil over the roots of a grove of oak trees, smothering the trees.15 In finding negligence, the court held that
the contractor knew or should have known the consequences of
mounding soil over tree roots. This case also set a new standard
for awarding damages in negligence cases.
Damages. In deciding how to compensate a property
owner for damaged trees, Minnesota courts have distinguished
between ornamental trees and standing timber or ill-formed trees.
If trees that are ill-formed or serve merely to prevent erosion
or curtail noise are injured, the courts have based damages on
diminution in land value, i.e., the difference in the
land value before the injury and afterward. If trees are primarily
ornamental or shade trees, the court has said that the jury may
consider replacement cost, to the extent that the cost is reasonable
and practical, as an alternative measure of damages. "Reasonable
and practical" replacement cost has been defined as:
The cost to replace the number, size, and species of trees
destroyed to the extent that: 1) replacement serves to substantially
restore the character and quality of the property appropriate
for the owner's enjoyment and intended use and 2) the cost of
replacement is not greatly disproportionate to the resulting
restoration of the owner's enjoyment and intended use of the
Act of God. A frequently heard excuse is that
damage caused by a fallen tree was an act of God. Not every tree
that falls over in a strong wind and causes damage is the result
of an act of God.17 To qualify as an act
of God in negligence cases, all of the following elements are
needed: 1) the accident must have happened from a force of nature
that was both unexpected and unforeseeable; 2) that force must
have been the sole cause of the accident; and 3) the accident
could not have been prevented by using reasonable care.18 A bolt of lightning is an act of God, if
it is the sole cause of an injury. However, a person is liable
if his own prior negligence combined with the act of God to cause
Trespass and Wrongful
Trespass to trees is a tort recognized separate from trespass
to land and carries a heavy penalty. Cutting a tree on someone
else's land without her permission is a trespass to the tree.19 The penalty for intentional, wrongful tree
removal is treble damages. In Minnesota, a landowner whose trees
were bulldozed and buried on his land without his permission
was awarded both treble damages for the trespass to his trees
and punitive damages for the trespass to his land.20
An example of involuntary or casual trespass to the tree is illustrated
in a Minnesota court case where a driver had a heart attack and
drove into a grove of Colorado Spruce trees.21
Although the tree damage or "trespass" was not malicious,
it occurred without the permission of the trees' owner and the
court awarded him single damages. There are also penalties for
criminal trespass and criminal damage to property.22
Utility Company Pruning. A common urban sight
is the row of trees under a power line cut in a deep v-shape.
You may have a client who wants to sue a utility company for
its tree-trimming techniques or its removal of a tree. Your case
assessment should weigh aesthetics against the utility company's
duty to meet public demand to prevent power failures caused by
fallen tree limbs during storms.
Utility companies have easements across property in order to
provide electricity. Courts recognize the right of utility companies
to trim or remove trees within their easement, as long as the
work is reasonable and necessary to construct, use, operate,
or maintain power lines in the easement area.23
However, the utility company has a duty to remove power line
obstructions in a way that causes the least damage to the property
the power lines cross.
In a recent Minnesota case,24 the Supreme
Court confirmed that a property owner has an interest in the
trees on city land in front of her property and standing to sue
the utility company that removed a boulevard tree. However, the
Court also found that this right is subordinate to a utility's
right to trim or remove the trees to keep power lines clear.
The Court of Appeals decision that preceded the Supreme Court
case should be mandatory reading for any "budding"
tree lawyer, if only to brush up on clever tree puns, such as:
"stumped by the dismissal," "out on such a limb,"
"sapping the meaning," "fell on wooden ears,"
and "rooted in the common law."
In conclusion, even if you don't think of yourself as a tree-hugger,
you'll be acting in your client's best interests and protecting
our urban trees by giving the following advice: "Work it
out with your neighbor, or chat before you chop."
Steve Pihlaja is a solo practitioner in Minneapolis,
practicing in the areas of criminal defense and civil litigation.
He is a 1979 graduate of William Mitchell College of Law.
Lorrie Stromme is a lawyer, tree care advisor/master
gardener, president of the Minnesota Shade Tree Advisory Committee,
and a Hennepin County planner. She is a 1981 graduate of William
Mitchell College of Law.