HomeMy WebLinkAboutNo 873 Environmental Preservation and Protection of Trees and Woodlands
Ordinance 873
ENVIRONMENTAL PRESERVATION AND PROTECTION
OF TREES AND WOODLANDS
Purpose. The city desires to protect the trees and woodlands in the City of Maplewood. Trees
and woodlands provide better air quality, scenic beauty, protection against wind and water
erosion, natural insulation for energy conservation, and are beneficial in watershed
management. Trees and woodlands also provide wildlife habitat, privacy as screening, act as
natural sound and visual buffers, and increase property values. It is therefore the city’s intent to
protect, preserve, and enhance the natural environment of Maplewood and to encourage a
resourceful and prudent approach to development in the city; thereby, promoting and protecting
public health, safety, and welfare of the citizens of Maplewood. The purpose of this article is to
establish a tree preservation and protection ordinance to assure the continuance of significant
natural features for present and future generations which:
1. Preserve the natural character of neighborhoods (in developed and undeveloped areas).
2. Protect the health and safety of residents.
3. Protect water quality and minimize storm water runoff.
4. Prevent erosion or flooding.
5. Assure orderly development within wooded areas to minimize tree loss and environmental
degradation.
6. Establish a minimum standard for tree preservation and mitigation of environmental
impacts resulting from tree removal.
7. Establish and promote an on-going tree planting and maintenance program within the city
to assure trees and woodlands for future generations.
Applicability.
1. This article shall apply to any individual, business, or entity that engage in a building or
development project which requires issuance of a grading permit or new building permit.
This includes all sites of new development that contain significant trees or woodlots.
Platting and adding new roadway and right of way are subject to this ordinance.
2. The following are exceptions and are exempt from the requirements of this ordinance:
a. Minor home additions, general home improvements, and constriction of accessory
buildings (i.e. garage, shed).
b. Tree removal related to city public improvement projects to existing roadways, sewers and
other infrastructure, utility/infrastructure work or repair.
c. Emergency removal of a tree(s) to protect public health.
d. Restoration of land to native prairie. Prairie restoration must be approved by the
environmental manager or city forester.
e. Commercial tree nursery and landscape operations.
f. Removal of dead or dying trees.
Definitions.The following words, terms and phrases, when used in this article, shall have the
meanings ascribed to them in this section, except where the context clearly indicates a different
meaning:
Applicant means developer, builder, contractor or homeowner who applies for a building or
grading permit.
Caliper means a tree trunk measurement of nursery stock measured six (6) inches above
ground for tree trunks up to four (4) caliper inches. Tree trunks over four (4) caliper inches
measured at six (6) inches in height, move measurement point to twelve (12) inches above
ground to measure trunk caliper. Trees greater than four (4) caliper inches may have diameter
measurements.
City Forester means a tree inspector/forester certified by the State of Minnesota who is
employed by the city, or appropriate agent or independent contractor designated by the city.
Must meet the definition of a Maplewood Registered Forester.
Coniferous/Evergreen Tree means a woody plant having foliage on the outermost portions of
the branches year-round which at maturity is at least twelve (12) feet or more in height.
Tamaracks and Larch are included as coniferous tree species.
Critical Root Zone (CRZ) means an imaginary linear circle surrounding the tree trunk with a
radius distance of one (1) foot per one (1) inch of tree diameter (e.g., a sixteen (16) inch
diameter tree has a CRZ with a radius of sixteen (16) feet.
Deciduous Tree means a woody plant, which sheds leaves annually, having a defined crown
and at maturity is at least fifteen (15) feet or more in height.
Diameter means a standard point of measurement of tree size, measurement of tree trunk in
inches at a height of four and one half (4.5) feet above ground. Measure the circumference of a
tree trunk in inches at four and one half (4.5) feet above ground and divide by (3.14) to
determine diameter.
Drip Line means the farthest distance around and away from the trunk of a tree that rain or dew
will fall directly to the ground from the leaves or branches of that tree.
Environmental Manager means an employee of the city who manages city-wide environmental
programs, or appropriate agent designated by the city.
Hardwood Deciduous Tree means the following tree species: ash, basswood, birch, black
cherry, catalpa, hackberry, hickory, ironwood, hard maples (sugar maple or red maple), locust,
oak, and walnut.
Major Home Addition means an addition on a single or double dwelling lot of which the addition
or accessory building is more than a sixty (60) percent increase in the footprint of the single or
double dwelling structure on said lot.
Maplewood Registered Forester means a person who is registered with the city as a consulting
forester and holds a minimum of a Bachelor of Science degree in arboriculture, urban forestry or
similar field from an accredited academic institution or is registered with the International
Society of Arboriculture as a certified arborist/forester.
Minor Home Addition means an addition on a single or double dwelling lot of which the addition
or accessory building is less than a sixty (60) percent increase in the footprint of the single or
double dwelling structure on said lot.
Ornamental Tree means a woody plant, which is grown for its beauty of its foliage and flowers.
Retaining Wall means a structure utilized to hold a slope in a position in which it would not
naturally remain.
Specimen Tree is a healthy tree of any species twenty-eight (28) inches in diameter or greater.
These trees are considered Significant Trees.
Significant Natural Feature means a significant water body, woodlot, significant slope, or a site
of historical or archeological significance that has been recorded with the state.
Significant Tree means a healthy tree measuring a minimum of six (6) inches in diameter for
hardwood deciduous trees, eight (8) inches in diameter for coniferous/evergreen trees, twelve
(12) inches diameter for softwood deciduous tree, and specimen tree of any species twenty-
eight (28) inches in diameter or greater as defined herein. Buckthorn or other noxious woody
plants as determined by the environmental manager are not considered a significant tree
species at any diameter.
Slope means the inclination of the natural surface of the land from the horizontal; commonly
described as a ratio of the length to the height.
Structure means anything manufactured, constructed, or erected which is normally attached to
or positioned on land, including portable structures.
Softwood Deciduous Tree means the following tree species: box elder, cottonwood, elm,
poplar/aspen, silver maple, and willow.
Tree Preservation Plan means a plan prepared with the assistance of a certified forester, which
clearly shows all trees in the area to be developed or within the parcel of record. The plan
should include all significant trees to be preserved and measures taken to preserve them. The
plan will also include calculations to determine the number of replacement trees as required by
the tree mitigation schedule and a proposed re-forestation landscape plan.
Utility means electric, telephone, telegraph, cable television, water, sanitary or storm sewer,
solid waste, gas or similar service operations.
Vegetation means all plant growth, especially trees, shrubs, native wildflowers, mosses or
grasses.
Wetlandas defined in the city’s wetland ordinance.
Wilding Tree means a tree that was not grown or maintained by a nursery.
Woodlotmeans a treed area of at least one- quarter (1/4) acre on a vacant lot, which includes
significant tree(s).
Woodlot alteration permit. A woodlot alteration application shall be submitted to the
environmental manager for review prior to removal of any living trees on a woodlot that is not
reviewed by another application. The applicant shall submit a tree plan and any other
information needed to determine compliance with this ordinance. Specific requirements shall be
stated on an application form in the office of the environmental manager. An application fee
shall be established yearly by the city council by resolution. Failure to submit an approved
woodlot alteration application before removal of any trees will result in a two-year
moratorium for issuance of a city grading or building permit. In addition, a total tree
replacement for the parcel as outlined in the tree mitigation/replacement schedule with
the assumption that all trees that were removed are significant trees.
The environmental manager may approve a woodlot alteration permit that complies with this
ordinance and receive recommendations from the city forester concerning the proposed woodlot
alteration. The applicant may appeal environmental manager’s decision to the environmental
committee in writing within fifteen (15) days of the environmental manager’s written decision.
The applicant may appeal the environmental committee decision in writing within (15) days of
the environmental committee written decision to city council for final decision. Applicant must
first approach environmental manager then environmental committee before city council will
review.
Tree preservation plan. A tree preservation plan is required for any project which
requires any land use permit, grading permit, or building permit; excluding minor home
additions and the removal of dead, diseased, dying or hazardous trees of any size. A tree
preservation plan shall reflect the applicant’s best effort to determine the most feasible and
practical layout of buildings, parking lots, driveways, streets, storage and other physical
features, so that the fewest significant trees are destroyed or damaged and to minimize the
negative environmental impact to the site. All tree replacements will be in addition to landscape
tree planting standards. An applicant may request a waiver from the environmental manager
from preparation of a tree preservation plan.
Tree preservation plans shall include the following:
1. A tree inventory overlay on the site plan that shows size, species, general health, and
location of all significant trees located within the area to be developed or within the parcel
of record. Location of groups of standing dead or diseased significant trees shall be noted
on inventory overlay.
All tree inventories shall be performed by a certified forester and shall be consistent with
the engineer’s grading plan contours.
All significant trees included in the tree inventory must be tagged in the field for reference
on the tree preservation plan. These significant trees should be identified on the plan
sheet(s) in both graphic and tabular form. Trees growing in clump form are considered
individual trees and each stem/trunk is measured as individual trees.
2. A certified forester must approve the tree preservation plan.
3. The tree preservation plan must be drawn at the same scale as the other site plan
submittals.
4. A tree preservation plan that coincides with necessary engineering documents such as
topography, wetland information, grading plans, road, and building locations must include:
a. A list of total diameter inches of all healthy significant trees inventoried.
b. Listing of the total diameter inches of healthy significant trees removed.
The name(s), telephone number(s), and address(s) of the person(s) responsible for tree
preservation during the course of the development project.
5. Outer boundaries of all contiguous wooded areas, with a general description of trees not
meeting the significant tree size threshold and any indication of the presence of epidemic
tree diseases.
6. Delineation of all limits of land disturbance, clearing, grading and trenching.
7. Locations of the proposed buildings, structures, or impervious surfaces.
8. Location of trees protected and the proposed measures for protection including delineation
of tree protection fencing, tree protection signs, location for material storage, parking,
debris storage, and wash out area for redi-mix trucks.
9. Written description of tree preservation and safeguarding measures planned for the site.
10. Size, species, number, and location of all replacement trees proposed to be planted on the
property in accordance with the tree mitigation/replacement schedule.
11. Signature of the person(s) preparing the plan.
The tree preservation plan shall be reviewed by the environmental manager, with advisement
from the city forester, for compliance with this ordinance. Reasons for denial shall be noted on
the tree preservation plan, or otherwise stated in writing.
Tree Preservation and Safeguarding Tree Measures.
1. All developments within the city shall be designed to preserve significant trees and
woodlots, where such preservation would not affect the public health, safety or welfare of
Maplewood citizens. The city may prohibit removal of all or a part of a woodlot or
significant tree subject to the limitations as defined in this chapter. This decision shall be
based on but not limited to the following criteria:
a. Size.
b. Species, health, and attractiveness of the trees, including:
1) Sensitivity to disease.
2) Life span.
3) Nuisance characteristics.
4) Sensitivity to site grading.
5) Potential for transplanting.
6) Need for thinning a woodlot.
7) Effects on the functioning of a development.
8) Fragmentation of wooded area and effects on wildlife corridors.
9) The public health, safety and welfare.
10) Effects on wetlands and/or watershed.
11) Native Prairie Restoration.
2. Safeguarding preserved trees: the tree preservation plan shall delineate the location of
(existing) significant trees that are to be preserved with location and type of protective
fencing.
a. Tree protective areas shall be located at a minimum of the CRZ of trees or drip line
whenever possible. Use of tree-save islands and stands are encouraged rather than the
protection of individual trees scattered throughout a site.
b. Suitable tree protection fencing in active areas includes use of orange polyethylene
laminar safety fencing or woven polyethylene fabric (silt fencing). Fencing must be self-
supportive. All active tree protection areas shall be designated as such with “Tree Save
Area” signs posted in addition to the required fencing.
c. Use of passive forms of tree protection requires approval from environmental manager in
writing. Passive forms of tree protection fencing include use of continuous rope or flagging
(heavy mil plastic four (4) inches or wider) with visible signage stating “Keep Out” or “Tree
Save Area”.
d. Sings requesting subcontractor cooperation and compliance with tree protection standards
are required at site entrances.
e. No construction work shall begin until tree protection fencing has been installed,
inspected, and approved by the city forester. At least three (3) working days prior to
construction or grading, applicant shall be required to request inspection of on-site
protective measures by city forester. Once city forester approves tree protection fencing or
devices it must not be altered or removed without prior written approval.
f. Tree protection fencing shall be maintained and repaired by the applicant for the duration
of construction. No grade change, construction activity, storage or staging of materials
shall occur within this fenced area.
g. Use of custom grading, retaining walls or tree wells to maintain existing grade for
preserved trees.
h. Layout of the project site utility and grading plans should accommodate the tree
preservation areas. Utilities recommended along corridors between tree preservation
areas and use of common trenches or tunnel installation if possible.
i. Minimize tree wounding by felling or removing trees away from trees remaining on site.
j. Construction site activities such as parking, material storage, concrete washout,
placement of holes, etc., shall be arranged so as not to encroach on tree protection areas.
k. Identify and prevent oak wilt infection. Treat all known oak wilt infected areas with current
accepted guidelines including root cutting and tree removal. If pruning oaks is required
between April 1 and July 1 cover fresh wounds with nontoxic tree wound sealant or latex
paint.
l. Use of wood chip mulch to a depth of six (6) to eight (8) inches adjacent to tree protection
areas to minimize soil compaction and desiccation.
m. Concrete washout, leakage or spillage of fuels or paints, or other materials that would
result in detrimental change in soil chemistry is prohibited in tree preservation areas.
n. Post construction tree care to mitigate construction damage:
1) Tree root aeration, fertilization, and/or irrigation systems.
2) Therapeutic pruning.
o. Soil compaction mitigation by:
1) Mulch drive lanes with eight (8) to ten (10) inches of woodchips.
2) Soil fracturing with deep tillage or other similar methods.
3) Inclusion of organic matter to existing soil.
4) Core aeration.
p. Transplant existing trees to a protected area for future transplanting onto permanent sites
within the construction area.
3. If any significant tree stated as preserved (protected) in the approved tree preservation
plan is cut, damaged, or encroached upon by grading equipment or during the
construction process without city authorization and is determined by the environmental
manager that the damaged tree(s) will probably not survive, the said damaged tree(s) shall
be removed by the applicant at their expense and replacement tree(s) required at a rate of
two (2) times the tree mitigation/replacement formula.
Tree Mitigation/Replacement Schedule.
If less than twenty percent (20%) of significant tree diameter inches is removed, the applicant
shall replace one (1) tree per significant tree removed. Tree replacement shall be a minimum of
two (2.0) caliper inches in size.
If twenty percent (20%) or more total diameter inches is removed, applicant shall mitigate all
significant diameter inches using the tree mitigation/replacement schedule in accordance with
the following formula:
A = Total Diameter Inches of Significant Trees lost as a result of the Land Alteration
B = Total Diameter Inches of Significant Trees situated on the property.
C = Tree Replacement Constant (1.5)
D = Replacement Trees (Number of Caliper Inches)
((A/B - .20) x C) x A = D
Example
A = 379
B = 943
C = 1.33
D = 160
((379 / 943 - 0.20) x 1.5) x 379 = 114.7 caliper inches
The trees required to be replaced pursuant to this chapter shall be in addition to any other trees
required to be planted pursuant to any other provision of city code.
Once the total caliper inches for replacement trees are determined, the developer/applicant
shall mitigate tree loss by either:
1. Plant replacement trees in appropriate areas within the development in accordance with
the tree replacement schedule.
2. Plant replacement trees on city property under the direction of environmental manager or
city forester. Must be approved during the review process prior to issuance of permit(s).
3. Pay the city a sum per diameter inch in accordance with the tree replacement schedule
with written approval from city staff. The fee per diameter inch shall be set forth in the city
fee schedule set annually by city council resolution. Payment shall be deposited into an
account designated specifically for tree planting on public property within the city. The form
of mitigation to be provided by the applicant shall be determined by city staff. This
provision may only apply if all other measures in this ordinance have been exhausted.
4. The developer shall be required to maintain trees for two (2) years after planting. Should
any tree require replacement during this two (2) year period, the replacement period shall
start at the date of replacement. Trees required to be planted pursuant to any other
provision of city code are not included in this and must be replaced according to such
code.
5. Species requirements: Where ten (10) or more replacement trees are required, not more
than thirty (30) percent shall be of the same type of tree without the written approval of the
environmental manager. Native tree species to the Maplewood area are preferred.
6. Sources of trees: Replacement trees shall consist of certified nursery stock as defined by
Minnesota Statues, Section 18.46 hardy for this USDA plant hardiness zone (Zone 2,3, or
4 hardiness rated trees) or other trees including wilding trees, so long as such wilding
trees comply with the following standards and are approved by the environmental
manager or city forester. All replacement trees shall be healthy and free from insect or
disease infestation. A wilding tree measured in caliper inches shall not exceed the
maximum height as shown on the table below:
CALIPER INCHES MAXIMUM HEIGHT (FEET)
2-3 18
3-4 20
4-5 24
The lowest branch of a wilding tree shall not be at a height above the surface of the
ground more than one-half (1/2) the total height of the tree (e.g., a fourteen (14) foot tree
must have a branch within seven (7) feet of the surface of the surrounding ground).
7. Tree replacement size must be no less than two (2) caliper inches deciduous or six (6) foot
evergreen tree unless pre-approved by the environmental manager. Evergreen or
coniferous tree height convert to caliper measurement as follows: the first six (6) feet of
growth equals two and one-half (2.5) caliper inches for each additional two (2) feet in
height equals one (1) additional caliper inch. Trees required to be planted pursuant to any
other provision of city code must comply with tree size specification of such code.
8. Tree replacement surety required. The applicant shall post tree replacement surety with
the city, such as a tree replacement cash deposit or letter of credit, of one hundred and
fifty (150) percent of estimated cost for tree replacement for proposed planting. Funds will
be held by the city until successful completion of final planting inspection. It shall be the
applicant’s responsibility to call for such inspection. Tree replacement surety does not
include other sureties required pursuant to any other provision of city code or city directive.
Enforcement. The city reserves the right to inspect the construction site at any time for
compliance with this ordinance. Should the city find the site in violation of the approved tree
preservation plan, they may issue a stop work order until conditions are corrected. Stop work
order will be lifted after approved by environmental manager or city forester in writing.
The city shall be responsible for the enforcement of this ordinance. Any person who fails to
comply with or violates any section of this ordinance shall be deemed guilty of a misdemeanor
and, upon conviction, shall be subject to punishment in accordance with section 1-15. All land
use building and grading permits shall be suspended until the developer has corrected the
violation. Each day that a separate violation exists shall constitute a separate offense.
Effect on density. The city may reduce the maximum allowed density on that part of a
development that has a significant natural feature, where such reduction would save all or part
of a significant natural feature. However, regardless of the requirements in this article, the
maximum allowed density shall not be reduced below 67 percent of the allowed density in the
city’s land use plan for multiple dwellings. The minimum lot size shall not be increased above
15,000 square feet for single dwellings. Any required density reduction or increase in lot size
must save a significant natural feature. The city council may require the clustering of dwellings
in the form of townhouses, quads, apartments, or similar uses where it is necessary to preserve
significant natural features.
Passed by the Maplewood City Council on September 11, 2006.