Bismarck Forestry Division Arboricultural Specifications and Standards Of Practice

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Allan Goodman
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1 Bismarck Forestry Division Arboricultural Specifications and Standards Of Practice As Authorized by City Ordinance Title 13 (Revised September, 2011) Section 1. Arboricultural Specifications and Standards of Practice. The City Forester shall have the authority to promulgate the rules and regulations of the Arboricultural Specifications and Standards of Practice, which also may be known as the Forestry Standards, governing the planting, maintenance, removal, fertilization, pruning, and bracing of trees on streets or other public sites in the City of Bismarck, North Dakota, with the approval of the Forestry Advisory Board. Section 2. Policy. (A) All work on public trees shall comply with the City Tree Ordinance of the City of Bismarck, North Dakota. (B) The Arboricultural Specifications and Standards of Practice shall be adhered to at all times, but may be amended at any time that experience, new research or laws indicate improved methods, or whenever circumstances make it advisable, with the approval of the Forestry Advisory Board. (C) The policy of the Division of Forestry shall be one of cooperating with the public property owners, other City departments, and appropriate non-profit organizations at all times. (D) No trees shall be removed from public property unless they constitute a hazard to life or property, a public nuisance as defined in City Ordinance Title 13, or because the revision of planting plans necessitates. Section 3. Species, Cultivars and Varieties. (A) The Division of Forestry shall develop a Partners In Planting pamphlet on an annual basis with species, cultivars and varieties that are accepted for planting on street right-of-way and on other public property in the City of Bismarck. (B) Only desirable long-lived trees of good appearance, beauty, adaptability, and generally free from injurious pests or diseases shall be planted in public sites. The City Forester shall periodically review the species, cultivars and varieties included on the approved list to determine if any should be removed for any reason, or if certain new species, cultivars or varieties of proven dependability and value should be added. (C) Where street blocks have been assigned a particular species or variety as identified in specific City Master Plans, only these shall be planted subject to revision by the City Forester and approval by the Board. (D) Species not acceptable for right-of-way planting and reasons include: Genus Populus producing the pistillate flowers and bearing the cotton filled seed capsules (City Ordinance Title 13) Ulmus pumila or Siberian elm (City Ordinance Title 13) Any Fraxinus species or ash species (Emerald Ash Borer) Prunus virginiana or Canada Red Chokecherry (Black Knot, suckering issues and numerous stem and trunk canker diseases) Betula papyrifera or Paper birch (Bronze Birch Borer) Picea species or spruce species (low branch structure causes visibility issues)

2 Section 4. Planting. Page 2 (A) Size. (1) Unless otherwise specified by the City Forester, all medium or large deciduous tree species and their cultivars and varieties shall conform to the current American Standard for Nursery Stock and be at least 1½ inches in diameter six (6) inches above ground level, and at least eight (8) to ten (10) feet in height when planted. The tree shall have a well branched crown typical of the species. (2) All small deciduous tree species and their cultivars or varieties shall conform to the current American Standard for Nursery Stock and be at least 1 inch in diameter six (6) inches above ground level, and at least five (5) to six (6) feet or more in height and have six (6) or more branches. (B) Grade. (1) Unless otherwise allowed for specific reasons, all trees shall have comparatively straight trunks, well developed leaders and tops, and roots characteristic of the species, cultivar or variety showing evidence of proper nursery pruning. All trees must be free from insects, disease, mechanical injuries, and other objectionable features at the time of planting. (C) Location and Spacing. (1) Following is the accepted species, cultivar and varieties list and the minimum width between the street-side edge of the sidewalk and the face of the curb that each tree shall be planted in based on a forty (40) year cycle: (a) Extra Large Trees Autumn Gold Ginkgo Northern Catalpa Silver Maple Boulevard Width 9 ½ or larger 9 ½ or larger 9 ½ or larger (b) Large Trees (50 +) Ash species **NOT ALLOWED ON BOULEVARD** Black Walnut Bur Oak Common Hackberry Elm species **Dutch Elm Disease Resistant Hybrid Cultivars only** Kentucky Coffeetree Sienna Glen Maple Swamp White Oak (c) Medium Trees (30-50 ) American Linden Amur Corktree Black Locust Harvest Gold Linden Ironwood Larch Laurel Leaf Willow Little Leaf Linden Norway Maple Ohio Buckeye Prairie Horizon Manchurian Alder Red Maple Sugar Maple Thornless Honeylocust (d) Small Trees (less than 30 ) Amur Maackia Amur Maple Copper Curls Pekin Lilac Crabapple Japanese Tree Lilac

3 Mountain Ash Prairie Gem Flowering Pear Princess Kay Plum Serviceberry Snowbird Hawthorn Tatarian Maple Thornless Cockspur Hawthorn Toba Hawthorn Page 3 (e) Where overhead lines or building setbacks present a special problem, the selection of site and species shall be determined by the City Forester. (2) Where trees are to be planted on streets where the boulevard is less than four (4) feet in width, legal steps should be taken to obtain easement rights to plant beyond the sidewalk on private property. Such easements should contain provisions granting the City permission to select, plant, maintain and remove such trees under the direction of the City Forester. (3) Trees shall be planted at least forty (40) feet from street curb line intersections and at least ten (10) feet from driveways and alley rights-of-way. (4) No tree shall be planted closer than ten (10) feet to a utility pole, water service line, street light or fire hydrant. (5) Spacing of trees shall be determined by the City Forester according to local conditions, species, cultivars or varieties used, and their mature height, spread, and form. Generally, all large trees shall be planted forty (40) feet on center, all medium sized trees shall be planted a minimum of thirty (30) feet on center, and all small trees shall be planted a minimum of twenty (20) feet on center. (6) All planting on unpaved streets without curbs must have the special permission of the City Forester who shall determine the tree s location so it will not be injured or destroyed when the street is curbed and paved. (7) Placement of trees shall be such as not to interfere with mailboxes. (D) Methods of Planting and Support. (1) Most small deciduous trees may be planted bare-rooted unless otherwise indicated. Roots of bare-rooted trees should be protected against drying out. (2) All coniferous trees shall be planted balled and burlapped, basket, and/or planted with a mechanical tree mover approved by the City Forester. Balled roots should be prevented from drying out at the surface of the ball and protected against injurious freezing. (3) Pits dug for planting of bare-rooted plants shall be a minimum of twelve (12) inches larger in diameter than the diameter of the root system so as to be of sufficient size to accommodate the roots without crowding. For balled trees the pits shall be a minimum of twelve (12) inches larger in diameter than the diameter of the ball of soil to allow proper backfill. (4) Plants shall be planted so that the root flare is at the finished soil line. (5) In poorly drained soil, artificial drainage shall be provided to properly drain the soil about the plant roots or tolerant species selected. (6) The soil excavated from the planting pits shall be used for backfilling the plant. All stones larger than 1 in diameter shall be removed and all lumps or clods shall be broken up before backfilling. (7) Pruning at the time of transplanting shall consist mainly of removing broken, dead, crossed and rubbing branches and any remedial pruning necessary to improve the plants basic branch structure. The central leader shall not be removed, shortened or otherwise destroyed.

4 Page 4 (8) Trees shall be suitably wrapped and guyed, or supported in an upright position according to accepted arboricultural practices. The guys or supports shall be fastened so that they will not girdle or cause serious injury to the tree or endanger public safety. (E) Planting in the Sidewalk. (1) In those situations where trees are to be planted in the sidewalk, only those species and planting techniques specified by the City Forester and approved by the Forestry Advisory Board shall be allowed. Tree Grates/Protective Fences/Planting Treatments 1 Tree Grates. Where sidewalk width is less than 8-feet and new trees will be installed in a tree well, metal tree grates shall be used and approved by Forestry. Minimum size grates shall be 5 x 5 unless specified otherwise. All tree grates shall be mounted in frames, frames inset into a concrete foundation within the sidewalk or surface material and shall be flush with the surrounding surface. 2 Engineered Soils. Occasionally, tree planting must occur in poor or difficult soil where standard planting techniques will result in poor-to-average performance or mortality (such as unique or unusual regional geology, slope, soil volume, restrictive physical or chemical properties, poor drainage, etc.). In this case, the responsible party must investigate alternative solutions to enable long term tree growth. Alternative planting specifications or plans that vary from the native or typical soil conditions shall be submitted to the City Forester for approval prior to installation. 1 Care and maintenance of the desired treatment shall be the responsibility of the property owner. Once the treatment poses a trip hazard or risk to the public the property owner shall make repairs to mitigate the problem that conforms to city standards. Section 5. Early Maintenance. (A) General. (1) Newly planted trees require special attention to maintenance practices during one or two growing seasons following planting. All maintenance practices shall follow approved arboricultural standards. (B) Watering. (1) Ample soil moisture shall be maintained following planting. A thorough watering each five (5) to ten (10) days, depending on soil type and drainage provisions, is usually adequate during the growing season. A soil auger or sampling tube is used to check the adequacy of moisture in the soil ball and/or backfill. (2) City planting projects shall install a tree watering device such as a Tree Gator to ensure adequate water is applied. Property owners will be encouraged to install such a device if no irrigation system is present. (C) Fertilization. (1) Fertilization shall follow the current American National Standard for Tree Care Operations Tree, Shrub, and Other Woody Plant Maintenance Standard Practices (Fertilization) and the International Society of Arboriculture Best Management Practices Fertilization. (D) Insect and Disease Control. (1) Measures for the control of insects and diseases shall be taken as is shown necessary by frequent and thorough inspections. Where it is necessary to spray, insecticides or fungicides shall be used that are recommended for safe and effective control. (E) Pruning.

5 Page 5 (1) Pruning practices to be followed the first few years following planting shall consist of removing dead, broken, or injured branches, the suppression of rank, uneven growth and usually the removal of water sprouts. Water Sprouts and sucker growth shall be removed as it reaches pencil size in diameter. (2) Pruning shall be practiced subsequent to transplanting and as necessary thereafter to assure sturdy crotch development. (3) Tree canopy should be raised as growth characteristics and location dictate. Newly planted trees need not have lower branches removed until they are well established. Section 6. General Maintenance. (A) Pruning and Removal. (1) Pruning shall follow the current American National Standard for Tree Care Operations Tree, Shrub, and Other Woody Plant Management Standard Practices (Pruning) and the International Society of Arboriculture Best Management Practices Tree Pruning. No topping or dehorning of trees shall be permitted except with written permission of the City Forester. Proper cabling and bracing shall be substituted for this practice whenever possible. (2) All established trees shall be pruned to sufficient height to allow free passage of pedestrians and vehicular traffic. A clear height of ten (10) feet over sidewalks and thirteen and one-half (13½) feet over streets shall be maintained, except those streets that are subject to truck traffic which shall have a clearance of sixteen (16) feet. (3) It shall be the policy of the City Forester to cooperate with the City Engineer, and vice versa, in the placement and height of lighting standards, and the development of systems of tree pruning to give effective street illumination. (4) Pruning to allow for safe sight distance and reaction time to traffic devises shall conform to Traffic Engineering Standards. A minimum stopping sight distance for vehicular traffic shall be met at all intersections. (a) 200 feet = 25 mph (b) 250 feet = 35 mph (c) 305 feet = 40 mph (5) All cuts shall be made with a saw or pruner and only at the branch collar. No stubs shall be left. No spurs or climbing irons shall be used in the trees, except when trees are to be removed. (6) All dead, crossed, and rubbing branches shall be removed. (7) All tools being used on a tree suspected to be infected with a contagious disease shall be disinfected before being used on another tree. (8) Whenever streets are to be blocked off to public service, the Police and Fire Departments shall be notified of the location and the length of time the street will be blocked. Notification shall be given these departments upon the removal of such barriers or if such barriers are to remain longer than originally expected. (9) To protect the public from danger, suitable street and sidewalk barriers, highway cones, or signs shall be used when pruning a tree. Flashing signals or flares shall be placed on all barriers or obstructions remaining in the street after dark. (10) The stumps of all removed trees shall be cut to at least sixteen (16) inches below the ground. A small mound of stump grindings should be left in place since settling will occur. Any soil replacement and leveling of the site will be the responsibility of the property owner. (B) Spraying. (1) Suitable precautions shall be taken to protect and warn the public that spraying is being done.

6 Page 6 (2) Spraying shall be done only for the control of specific diseases or insects, with the proper materials in the necessary strength, and applied at the proper time to obtain the desired control. All spraying practices shall conform to federal and state regulations. (3) Dormant oil sprays shall be applied only to certain species of trees as approved by the City Forester and only when the air temperature is 40 F or above and when it is not likely to drop below this temperature for a period of twenty-four (24) hours. (4) With the approach of EAB, the city will not inject ash species. It is recommended by the ND Dept of Ag and the NDFS that chemical treatments be held off till the invasive pest is within 15 miles of the city. If the homeowner wishes to inject public trees they must obtain a permit from the City Forester. (C) Cabling and Bracing. (1) As a general rule, cables should be placed approximately two-thirds (2/3) of the distance between the crotch and top branch ends. Rust resistant cables, thimbles, and lags should be used. The ends of the cable should be attached to hooks or eyes of lags or bolts, and thimbles must be used in the eye splice in each end of the cable. In no instances shall cables be wrapped around a branch. (2) All cabling and bracing practices shall follow current American National Standard Tree, Shrub, and Other Woody Plant Maintenance Standard Practices (Supplemental Support Systems) and the International Society of Arboriculture Best Management Practices Tree Support Systems: Cabling, Bracing, Guying, and Propping. (3) Ash species on public property will not be cabled and braced, these trees will be placed on the removal list. If the homeowner wishes to contract with a licensed tree service to perform the work they most obtain a permit from the City Forester. (D) Augering and Trenching. (1) Unless otherwise specified by the City Forester, the street tree root zone shall be protected by augering in the following manner: Tree Diameter (DBH): 0-2 inches: Augering is required if trench is located within a 1-foot radius from the base of the tree. 3-4 inches: Augering is required if trench is located within a 2-foot radius from the base of the tree. 5-9 inches: Augering is required if trench is located within a 5-foot radius from the base of the tree inches: Augering is required if trench is located within a 10-foot radius from the base of the tree inches: Augering is required if trench is located within a 12-foot radius from the base of the tree. 19 inches and over: Augering is required if trench is located within a 15-foot radius from the base of the tree. (2) The minimum depth of augering within the root zone, as described above, shall be 24 inches below the soil surface. No trenching within the root zone of the tree, as described, shall be permitted unless authorized by the City Forester. (3) Tree Protection Zones shall be followed at all times as outlined in the City Ordinance Title 13.

7. A saucer of soil shall be formed so that water is directed down through the roots or root ball rather than around the root ball.

7. A saucer of soil shall be formed so that water is directed down through the roots or root ball rather than around the root ball. Adopted 12/5/00; revised 3/5/02 Marietta Tree Commission Rules and Regulations I. Tree Planting A. Planting Specifications These specifications are Adapted from recommendations of the OSU Extension Service.