Attachment 2- Diseased Trees (Amendment to Chapters 13 cc report Rev1) Y
� w
9 S CITY OF ClIANIIASSEN
Chanhassen is a Community for Life-Providing for Today and Planning for Tomorrow
MEMORANDUM
TO: Todd Gerhardt, City Manager
FROM: Jill Sinclair, Environmental Resources Specialist
DATE: September 25, 2017
SUBJ: Amendments to Chapter 13, Article IV—Control and Prevention of Diseased
Trees
ISSUE
In advance of the confirmation of emerald ash borer(EAB) in Chanhassen,the city should
update the Diseased Tree ordinance to include future epidemic pests and diseases. Additionally,
the city is routinely contacted by residents who are concerned about the potential risk posed to
their safety and property by their neighbor's hazard trees.
BACKGROUND
The city's existing diseased tree ordinance targets specific diseases which means that the city
lacks an enforcement mechanism for addressing emerging threats to the city's trees, such as
EAB. Current city code references the specific epidemic diseases Dutch elm disease and oak
wilt,but does not include insect pests that are epidemic. Revising the city code to reflect all
potential tree epidemics, including pests and other diseases, allows the city the flexibility to
respond to any threats upon our urban forest as identified by the Minnesota Department of
Agriculture.
Trees which have contracted epidemic diseases or pest infestations can present a risk of infection
to other healthy trees within the community. The specific nature of the existing ordinance means
that staff cannot always act proactively to address emerging threats to our tree inventory. The
inability to act at the first signs of an epidemic pest or disease increases the chances that the pest
or disease will become established more quickly within our community, potentially resulting in
substantial loses to our tree inventory.
Additionally, dead and dying trees can impact public safety through their fall risk. Citizens
regularly contact the city requesting that we address hazard situations created by dead or dying
trees located on adjacent properties. Often times when investigating citizens' concerns about the
potential safety risks proposed by diseased or dead trees, staff is unable to address the issue
PH 952.227.1100• www.ci.chanhassen.mn.us• FX 952.227.1110
7700 MARKET BOULEVARD • PO BOX 147 • CHANHASSEN • MINNESOTA 55317
Todd Gerhardt
Amendments to Chapter 13, Article IV—Control and Prevention of Diseased Trees
September 25, 2017
Page 2 of 7
because the tree in question does not fall into one of the two categories stipulated by the
ordinance.
Attached are the changes requested by staff. The changes reflect an update to City Code to allow
staff to address public health and safety issues related to broader epidemic pests/diseases and
citizen concerns regarding hazard trees.
SURVEY OF COMPERABLE CITIES
List of KFS Cities' Existing Nuisance Tree Ordinances
Hazzard Trees '
Oak Wilt Dutch Elm EAB General Clause* Specific General**
Chaska Yes Yes Yes No No Yes
Cottage Grove Yes Yes Yes No No No
Elk River Yes Yes Yes Yes No No i
Inver Grove Heights Yes Yes Yes No No Yes
Lino Lakes Yes Yes Yes No No Yes
Prior Lake No No No Yes Yes No
Rosemount No No No Yes Yes No
Savage Yes No No Yes Yes No
Shakopee Yes Yes Yes Yes No No
Stillwater Yes No No No Yes No
Chanhassen's Existing Nuisance Tree Ordinances
Chanhassen Yes Yes No No No No
*Cities with a general disease and pest clause classify any tree infected with an infectious disease
or pest as a nuisance.
**Cities with a general hazard tree provision do not specifically address trees,but have general
nuisance clauses which could be used to require the abatement of hazard trees.
ANALYSIS
Both Hennepin and Scott Counties are located in Minnesota's EAB quarantine zone and it is
only a matter of time until EAB is confirmed in Caver County. It is also likely that other
epidemic tree diseases and pests will emerge to further threaten our forests.
The best way to control for EAB and other emerging threats is to be able to proactively respond
to the first signs of an infestation or infection. Expanding our city's nuisance ordinance to
include EAB and all other epidemic tree diseases and pests will allow us to proactively address
these situations and increase the odds that we can slow or reduce their impact on our city.
Todd Gerhardt
Amendments to Chapter 13, Article IV—Control and Prevention of Diseased Trees
September 25, 2017
Page 3 of 7
The proposed changes to Chapters 13, Article IV of the city code reflect the need for the city
code to be more inclusive to future urban forests threats. The current code pertains to Dutch elm
disease and oak wilt specifically, with references to general diseases,but not pests, as noted by
the MN Dept. of Agriculture. While this allows us to address the most pervasive disease threats
to shade trees, staff recommends that the ordinance be amended to include a broader coverage of
diseases that includes pests in order to accommodate emerging and future forestry issues.
In addition to being focused on a small number of shade tree diseases, the current code does not
have any provisions allowing the city to address trees which present a safety risk to people or
property. Many times staff is left in the position of agreeing with a concerned citizen that a
neighbor's dead, damaged, or dying tree possess a risk to their property,but lacking the capacity
to address hazardous trees located on private property.
The city's current nuisance ordinance defines a nuisance as anything that"annoys, injures or
endangers the health, safety, comfort or repose of the public", "depreciates the value of the
property of the inhabitants of the city", or"in any manner renders the inhabitants of the city
insecure in life or in use of property."While arguing that the aesthetics of diseased and dying
trees creates a sufficient depreciation of property values to deserve classification as a nuisance
may be not the foremost concern, the fall risk presented by some of these trees can be significant.
Staff feels that including hazard trees, defined as dead or dying trees that have the potential to
fall on a target, such as people or property, in the city's nuisance ordinance would be in line with
the intent of the ordinance and with other nuisances defined therein.
Of the 10 similar cities staff investigated, nine had an ordinance capable of addressing EAB, and
six had structured their ordinance so that it could address any epidemic tree infection or
infestation. Seven of the ten cities also had a clause which could be used to require the abatement
of hazard trees. Four of these seven addressed hazard trees specifically, while the other three had
general clauses which could conceivably be applied to hazard trees. The proposed amendments
to the city code would be in line with those passed by other similar cities.
In summary,the proposed amendments included:
• Expanding the list of nuisances to include not only diseased trees,but also invasive pests
and insects and hazard trees;
• Include definition of hazard trees;
• References to Dutch elm disease and oak wilt are replaced with 'tree diseases and pests'
to be inclusive of future tree threats as directed by the MN Dept. of Agriculture.
Todd Gerhardt
Amendments to Chapter 13, Article IV—Control and Prevention of Diseased Trees
September 25, 2017
Page 4 of 7
ALTERNATIVES
1) Do nothing. The current code allows us to address epidemic shade tree diseases, such
as Dutch elm disease and oak wilt.
2) Amend Chapter 13 to allow staff to better address all the diverse forms of pests and
diseases that affect trees as well as hazard trees.
RECOMMENDATION
Staff recommends approval of the attached amendment to Chapters 13. All new language is
colored and deletions have been struck through.
The proposed revisions are as follows:
ARTICLE IV. - CONTROL AND PREVENTION OF DISEASED TREES
Sec. 13-27. -Declaration of policy.
The City of Chanhassen has determined that the health of the elm and oak trees within the
municipal limits is threatened by Epidemic Diseases and Pests. the fatal diseases known aJ
. - -- . -, e. . - . - - .•. -- . - .. -- . It has
further determined that the loss of elm and oak and othcr shads trees growing upon public and
private property will substantially depreciate the value of property within the city and impair the
safety, good order, general welfare and convenience of the public. It is declared to be the
intention of the council to control and prevent the spread of these diseases and pests, and this
article is enacted for that purpose, to conform to the policies and procedures embodied in
Minnesota Statutes, Chapter 89, as amended, and rules promulgated there under.
(Ord. No. 229, § 1, 11-28-94)
Sec. 13-29. - Shade tree disease program.
It is the intention of the city council to conduct a program of plant pest control pursuant to
the authority granted by M.S. § 18G.16 18G.01. This program is directed specifically at the
control and elimination of tree diseases and pests Dutch Elm disease fungus and elm bark
beetles and Oak Wilt fungus and is undertaken at the recommendation of the commissioner of
agriculture. The city forester shall act as coordinator between the commissioner of agriculture
and the city in the conduct of this program.
(Ord. No. 229, § 1, 11-28-94; Ord. No. 395, § 5, 5-9-05)
Sec. 13-30. -Nuisances declared; abatement; firewood storage,
Nuisances declared. The following are public nuisances whenever they may be found within
the City of Chanhassen:
(1) Any living or standing elm tree or part thereof infected to any degree with the Dutch
Elm disease fungus Ceratocystis ulmi (Buisman) Moreua or which harbors any of the
elm bark beetles Scolytus multistriatus (Eichh.) or Hylurgopinus rufpies (Marsh).
Todd Gerhardt
Amendments to Chapter 13, Article IV—Control and Prevention of Diseased Trees
September 25, 2017
Page 5 of 7
(2) Any dead elm tree or part thereof, including logs, branches, stumps, firewood, or other
Elm material from which the bark has not been removed as provided in M.S. § 4:93
1 8G.04.
(3) Any living or standing oak tree or part thereof infected to any degree with the Oak Wilt
fungus Ceratocystis fagacearum.
(4) Any dead tree in the Red Oak group, or part of any such tree, including logs, branches,
stumps, firewood, or other Red Oak material from which the bark has not been
removed.
(5) Other f;hadc trees with epidemic diseases or any insect and/or pest that threatens the
health of trees.
(6) Any tree which, in the opinion of the Tree Inspector has become or threatens to
become a hazard so as to adversely affect the public safety, whether such tree shall
be on public or private property.
(Ord. No. 229, § 1, 11-28-94)
Sec. 13-31. - Abatement.
It is unlawful for any person, firm, or corporation to permit any public nuisance as defined
in section 13-30 to remain on any premises owned or controlled by such person or entity him
within the City of Chanhassen. Such nuisance may be abated in the manner prescribed by this
article in addition to the criminal penalties provided for in this article.
(Ord. No. 229, § 1, 11-28-94)
Sec. 13-33. - Inspection and investigation.
(a) Annual inspection. The forester shall inspect all premises and places with the city as often as
practicable to determine whether any condition described in section 13-30 of this article
exists thereon. He/she shall investigate all reported incidents of infestation by Dutch Elm
fungus or elm bark beetles, or Oak Wilt, or other epidemic diseases or pests of shade trees
or hazardous trees.
(b) Entry of private premises. The forester or his/her duly authorized agents may enter upon
private premises at any reasonable time for the purpose of carrying out any of the duties
assigned him/her under this article.
(c) Diagnosis. The forester or his/her duly authorized representative shall identify diseased or
infested trees by generally accepted field symptoms such as, but not limited to, wilting,
yellowing of leaves, evidence of larva or insects, or staining of wood in accordance with
Minnesota Department of Agriculture Rules and Regulations AGR 106. Laboratory
confirmation by the Minnesota Department of Agriculture will be used only when it is
necessary.
(d) The Tree Inspector shall assess potentially hazardous trees. A hazard tree is a tree that
has structural defects in the roots, stem or branches that may cause the tree or part
Todd Gerhardt
Amendments to Chapter 13,Article IV—Control and Prevention of Diseased Trees
September 25, 2017
Page 6 of 7
thereof to fail, where such failure may cause personal injury or property damage to a
target. A `target' includes, but is not limited to people, vehicles, buildings, property,
etc. Trees without targets are not considered hazards even if they are likely to fail and
can be considered beneficial to habitat protection.
(Ord. No. 229, § 1, 11-28-94)
Sec. 13-34. - Abatement of shade tree disease nuisances.
In abating the nuisances defined in section 13-30, the forester shall cause the infected or
infested tree or wood to be spr-aye€1 treated,removed,burned, or otherwise effectively treated so
as to destroy and prevent as fully as possible the spread of epidemic diseases and pests of e,hadc
trees, including, but not limited to, Dutch Elm disease fungus, elm bark beetles, and Oak Wilt
Disease. Such abatement procedures shall be carried out in accordance with current technical and
expert opinions and plans as may be designated by the commissioner of agriculture.
(Ord. No. 229, § 1, 11-28-94)
Sec. 13-35. - Procedure for removal of infected trees and wood.
(a) Forester's abatement order. Whenever the forester finds with reasonable certainty that one or
more of the infestations defined in section 13-30 exists in any trees or wood in any public or
private place, the owner shall be notified by mail and ordered to remove, not more than 20
days from the date of the mailing of such notice, the same in a manner approved by the
forester. If the forester identifies a hazard tree, the property owner shall be notified by
mail and be leaving a notice on the property that the nuisance must be abated within a
specified time. If the owner fails to comply with the order, the city manager may act to
abate the nuisance. In the event that the owner cannot be contacted, the city shall send notice
by certified mail to the last known address of the owner of record, and shall then proceed
forthwith to abate the nuisance.
(b) Methods of disposal of diseased elm or infested trees. All diseased elm or infested trees
including the above ground parts thereof shall be properly disposed of by such methods
including debarking, chipping, and utilization as recommended by the MN Dept. of
Agriculture.
(c) Removal and disposal of diseased trees in the Red Oak group. All diseased oak trees in the
red oak group that wilt in July and August shall be identified, marked, and removed by April
1 of the following year in order to eliminate any spore formation on them the following May
or June. Trees in the northern red oak group include the northern red oak (Quercus rubra),
northern pine oak (Quercus ellipsoidalis), black oak (Quercus velutina), and scarlet oak
(Quercus coccinea). Methods of disposal include chipping and utilization.
(d) Control of overland spread of Oak Wilt. To control the overland spread of the disease, the
city shall avoid pruning or other mechanical damage during the most susceptible period of
May and June. The city forester may determine that emergency pruning by utility companies
is necessary during this susceptible period if trees interfere with utility lines. If wounding is
Todd Gerhardt
Amendments to Chapter 13, Article IV—Control and Prevention of Diseased Trees
September 25, 2017
Page 7 of 7
unavoidable during this period, as in the aftermath of a storm or when the tree interferes
with utility lines, a tree wound dressing shall be applied.
(e) Stumps of diseased elms and oaks and other trees affected by arboreal disease. Stumps of all
elm and oak trees shall be removed or debarked to the groundline to eliminate all
possibilities of beetle habitation or possibilities of spore formation.
(f) Special assessments. From time to time, the city shall list the total unpaid costs of abatement
attributable to such separate lot or parcel of land in this city. The council then may spread
said costs or any portion thereof against the property involved as a special assessment under
M.S. ch. 429 and other pertinent statutes, for certification to the county auditor and
collection the following year along with current taxes. The council may consider deferments
for hardship. The assessment may be deferred on homestead property if the owner is a
person 65 years of age or older who is retired and/or by virtue of total or permanent
disability for whom it would be a hardship to make the payments for tree removal(s).
(Ord. No. 229, § 1, 11-28-94)
g:\plan\city code\2017\various\amendment to chapters 13 cc report revl.doc