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NHC Tree and Landscaping Manual_2022-11 NEW HANOVER COUNTY TREE & LANDSCAPING MANUAL NHC Planning & Land Use, November 2022 Prepared in Accordance with New Hanover County Unified Development Ordinance Section 5.3, Tree Retention and Section 5.4, Landscaping and Buffering Page 1 of 38 CONTENTS Types of Regulated Trees ................................................................................................................................... 3 Documented Trees .......................................................................................................................................... 3 Significant Trees .............................................................................................................................................. 3 Specimen Trees ............................................................................................................................................... 3 Measuring Diameter at Breast Height (DBH) .................................................................................................... 4 Protection of Existing Trees During Construction ............................................................................................. 5 Tree Removal Mitigation Worksheet .................................................................................................................. 6 Type A: Opaque Buffer, Vegetation Only (Option 1)........................................................................................ 8 Type A: Opaque Buffer, Combination Berm and Vegetation (Option 2) ......................................................... 9 Type A: Opaque Buffer, Combination Fencing and Vegetation (Option 3) .................................................. 10 Permeable Fencing ....................................................................................................................................... 10 Solid Fencing ................................................................................................................................................. 10 Type B: Aesthetic Buffer, Vegetation Only (Option 1) ................................................................................... 11 Type B: Aesthetic Buffer, Combination Fencing and Vegetation (Option 2) ................................................. 11 Sight Angles at Road Intersections .................................................................................................................. 12 Example of Commercial Use with Buffer Strips ............................................................................................... 13 Example of Parking Lot Perimeters and Interiors ............................................................................................ 14 Parking Lot Perimeter Planting Strips .............................................................................................................. 15 Recommended Buffer and Screening Materials.............................................................................................. 16 Recommended Buffer and Screening Materials.............................................................................................. 17 Recommended Landscaping Materials ............................................................................................................ 18 Common Examples of Native Species ............................................................................................................... 0 Common Examples of Invasive Species............................................................................................................ 0 Native Trees in Highway 421 Area ..................................................................................................................... 0 Plot Sampling Methodology for Tree Inventory ................................................................................................. 1 Introduction ...................................................................................................................................................... 1 Terminology ..................................................................................................................................................... 1 Contractor Requirements ................................................................................................................................ 2 Tree Inventory Methodology ........................................................................................................................... 2 Establish Plot Centers ................................................................................................................................. 2 Tree Inventory Data Collection ................................................................................................................... 3 Tree Inventory Report ................................................................................................................................. 4 Basal Area Measurement Methodology ............................................................................................................. 5 Page 2 of 38 APPENDIX ........................................................................................................................................................... 6 Soil Preperation ............................................................................................................................................... 6 Tree Planting instructions................................................................................................................................ 7 Shurb planting ................................................................................................................................................ 13 GroundCover Planting ................................................................................................................................... 14 mulching ......................................................................................................................................................... 14 Tree Maintenance (Pruning) ......................................................................................................................... 15 Tree Transplanting ........................................................................................................................................ 17 Page 3 of 38 TYPES OF REGULATED TREES Click on type/species name for more information. DOCUMENTED TREES • Must be identified on tree inventory • Tree removal permit required Tree Types/Species Minimum Diameter at Breast Height (DBH) Dogwoods and American Hollies 4 inches Long Leaf Pine, Pond Cypress, Bald Cypress, and Hardwoods 8 inches Other Conifers 12 inches SIGNIFICANT TREES • Must be identified on tree inventory • Tree removal permit required • Must be retained or mitigated Tree Types/Species Minimum Diameter at Breast Height (DBH) Dogwoods, American Hollies, Magnolias, Native Flowering Trees 8 inches Long Leaf Pine, Pond Cypress, Bald Cypress, and Hardwoods 18 inches Other Conifers 24 inches SPECIMEN TREES • Must be identified on tree inventory • Cannot be removed without a variance • If removed without a permit, the penalty is 2x the mitigation fee • If removed with variance, mitigation required Tree Types/Species Minimum Diameter at Breast Height (DBH) Pond Cypress, Bald Cypress, Live Oak 36 inches Page 4 of 38 MEASURING DIAMETER AT BREAST HEIGHT (DBH) Page 5 of 38 PROTECTION OF EXISTING TREES DURING CONSTRUCTION NOTE: If a protected tree is substantially damaged or destroyed or dies within 3 years after completion of construction, then replacement trees shall be planted on the site with a total diameter equal to twice the diameter of the protected tree. (For instance, if a 16” DBH tree is damaged, eight 4” trees or sixteen 2” would be required for replacement.) Page 6 of 38 TREE REMOVAL MITIGATION WORKSHEET *Click here to download the worksheet* Aggregate Inches at DBH Specimen Trees Identified for Removal (Variance Required) Live Oak 36" or larger 0 Pond Cypress 36" or larger 0 Bald Cypress 36" or larger 0 Required Mitigation Inches 0 Native Trees Identified to be Retained On-Site Native unregulated trees a minimum of 2" DBH 0 Dogwoods, American Hollies 2-4" DBH 0 Long Leaf Pine, Pond Cypress, Bald Cypress, Native Hardwoods 2-8" DBH 0 Other Native Conifers 2-12" DBH 0 Native Documented Trees 0 Dogwoods, American Hollies 4-8" DBH 0 Long Leaf Pine, Pond Cypress, Bald Cypress, Native Hardwoods 8-18" DBH 0 Other Native Conifers 12-24" DBH 0 Existing Trees Growing in Mature Native Forests 0 Existing Trees Growing in Stands or Natural Clusters 0 TOTAL 0 Adjusted Mitigation Inches 0 Page 7 of 38 Significant Trees Identified for Removal Dogwoods, Magnolias, Native Flowering Trees, American Hollies 8" DBH or larger 0 Non-Specimen Long Leaf Pine, Pond Cypress, Bald Cypress, Hardwoods 18" DBH or larger 0 Other Conifers 24" or larger 0 Required Mitigation Inches 0 Trees Identified to be Retained On-Site Native unregulated trees a minimum of 2" DBH 0 Non-native unregulated trees a minimum of 2" DBH 0 Documented Trees Dogwoods, American Hollies 4-8" DBH 0 Long Leaf Pine, Pond Cypress, Bald Cypress, Native Hardwoods 8-18" DBH 0 Non-Native Hardwoods 8-18" DBH 0 Other Native Conifers 12-24" DBH 0 Non-Native Conifers 12-24" DBH 0 Existing Trees Growing in Mature Native Forests Aggregate inches (Determination by Certified Arborist or NC Licensed Forester Required) 0 Existing Trees Growing in Stands or Natural Clusters Stands or Clusters of primarily native species (Determination by Certified Arborist or NC Licensed Forester Required) 0 Stands or Clusters of primarily non-native species (Determination by Certified Arborist or NC Licensed Forester Required) 0 TOTAL NATIVE INCHES 0 TOTAL NON-NATIVE INCHES 0 TOTAL INCHES USED TO OFF-SET SPECIMEN TREE MITIGATION 0 Total Adjusted Mitigation Inches 0 Replacement Inches that Cannot be Accommodated On-Site Fee In-Lieu Required (based on mitigation fee of $200 per inch in County Fee Schedule) $ - Page 8 of 38 TYPE A: OPAQUE BUFFER, VEGETATION ONLY (OPTION 1) Planted materials shall provide approximately full opacity within one year of planting. See Screening Materials section for planting guidelines to achieve this level of opacity. Page 9 of 38 TYPE A: OPAQUE BUFFER, COMBINATION BERM AND VEGETATION (O PTION 2) Planted materials shall provide approximately full opacity to a height of 6 feet within one year of planting. See Screening Materials section for planting guidelines to achieve this level of opacity. Page 10 of 38 TYPE A: OPAQUE BUFFER, COMBINATION FENCING AND VEGETATION (OPTION 3) PERMEABLE FENCING If permeable fencing is used, planted materials shall provide approximately full opacity within one year of planting. See Screening Materials section for planting guidelines to achieve this level of opacity. Required fencing materials shall be located between the fence and the common property line. SOLID FENCING If solid fencing is used, planted material shall provide a minimum of approximately 50 percent visual opacity at the time of initial planting. See Screening Materials section for planting guidelines to achieve this level of opacity. Vegetation shall be planted between the fence and the nonresidential or attached structure if the required buffer is 15 ft. or less in width. In all other cases, required planted materials shall be located between the fence and the common property line. Page 11 of 38 TYPE B: AESTHETIC BUFFER, VEGETATION ONLY (OPTION 1) Planted materials shall provide approximately 50 percent opacity within one year of planting. See Screening Materials section for planting guidelines to achieve this level of opacity. Planted material shall consist of a minimum of two plant species that will result in different heights at maturity. TYPE B: AESTHETIC BUFFER, COMBINATION FENCING AND VEGETATION (OPTION 2) Planted materials, if used, shall provide approximately 50% opacity within one year of planting. See Screening Materials section for planting guidelines to achieve this level of opacity. Chain link or wire fencing cannot be used to meet the fencing requirement. Page 12 of 38 SIGHT ANGLES AT ROAD INTERSECTIONS OVERHEAD VIEW CROSS SECTION Page 13 of 38 EXAMPLE OF COMMERCIAL USE WITH BUFFER STRIPS Page 14 of 38 EXAMPLE OF PARKING LOT PERIMETERS AND INTERIORS Page 15 of 38 PARKING LOT PERIMETER PLANTING STRIPS Page 16 of 38 RECOMMENDED BUFFER AND SCREENING MATERIALS Shrubs Name At Maturity Average Height (H) Spread (S) Maximum Plant Spacing (Apart) Growth Rate Notes For One Row For Two-Tree Rows 100% Opacity 50% Opacity 100% Opacity 50% Opacity Cleyera japonica Japanese Cleyera 8’-10’ (H) 6’ (S) 3’ 8’ 3.3’ 16’ M needs to be pruned, intolerant of wet sites, tolerates full shade Ilex cornuta Chinese Holy 8’-10’ (H) 20’ (S) 10’ 26.7’ 12.7’ 53.3’ R tolerates salt and drought Ilex x 'Nellie R. Stevens' Nellie R. Stevens Holly 15’-20’ (H) 10’ (S) 5’ 13.3’ 6’ 26.7’ R drought tolerant Ilex vomitoria Yaupon Holly 10’-15’ (H) 9’ (S) 4.5’ 12’ 5.3’ 24’ M tolerates salt and heavy pruning Illicium anisatum Japanese Anise- tree 10’-12’ (H) 9’ (S) 4.5’ 12’ 5.3’ 24’ M tolerates heavy share Myrica cerifera Southern Waxmyrtle 10’-15’ (H) 9’ (S) 4.5’ 12’ 5.3’ 24’ M tolerates salt, wet sites Nerium oleander Oleander 10’-12’ (H) 8’ (S) 4’ 10.7’ 4.7’ 21.3’ R tolerates poor soils, salt, heat & pollution - poisonous Osmanthus x fortunei Fortunes Osmanthus 15’-20’ (H) 13’ (S) 6.5’ 17.3 8’ 34.7’ M needs room, tolerates salt Pittosporum tobira Japanese Pittosporum 10’-12’ (H) 12’ (S) 6’ 16’ 7.3’ 32’ S tolerates sandy soil & hot, dry sites Podocarpus macrophyllus Chinese Podocarpus 10’-15’ (H) 5’ (S) 2.5’ 6.7’ 2.7’ 13.3’ S tolerates salt, best in full sun Notes: 1. All plants listed for screening material are evergreen 2. A variety of plant materials should be used for screening including ornamental or flowing plants which are encouraged. 3. Growth rate approximations in height S = Slow – 1’ per year; M = Moderate – 1’ to 2’ per year; R = Rapid – above 2’ per year. Page 17 of 38 RECOMMENDED BUFFER AND SCREENING MATERIALS Trees Name At Maturity Average Height (H) Spread (S) Maximum Plant Spacing (Apart) For Two-Tree Rows Growth Rate Notes 100% Opacity 50% Opacity X Hesperotropsis leylandii Leyland Cypress 60’-70’ (H) 17’ (S) 16’ 68’ R withstands heavy pruning Ilex cassine Dahoon Holly 15’-25’ (H) 12’ (S) 11’ 48’ M tolerates salt, wet sites Ilex latifolia Lusterleaf holly 20’-30’ (H) 12’ (S) 11’ 48’ M drought tolerant, avoid full sun and winds Juniperus virginiana Eastern Redcedar 30’-40’ (H) 16’ (S) 15’ 64’ M tolerates salt, poor soils Ilex opaca ‘Savannah’ Savannah American Holly 20’-30’ (H) 18’ (S) 17’ 72’ S tolerates air pollution, avoid dry windy sites Magnolia grandiflora Southern Magnolia 50’-60’ (H) 35’ (S) 34’ 140’ M needs room, tolerates wet sites Prunus caroliniana Carolina Cherrylaurel 20’-30’ (H) 20’ (S) 19’ 80’ R tolerates heavy pruning Notes: 1. All plants listed for screening material are evergreen 2. A variety of plant materials should be used for screening including ornamental or flowing plants which are encouraged. 3. All trees used shall be no less than 3’ in height at planting. Table 5.4.4.D Transitional Buffer Types and Specifications 4. Growth rate approximations in height S = Slow – 1’ per year; M = Moderate – 1’ to 2’ per year; R = Rapid – above 2’ per year Page 18 of 38 RECOMMENDED LANDSCAPING MATERIALS Trees Acer saccharum subsp. Floridanum Southern Sugar Maple Acer rubrum Red Maple Amelanchier Canadensis Shadblow Serviceberry Betula nigra River Birch Cercis Canadensis Redbud Cornus florida Dogwood Diospyros virginiana Common Persimmon Eriobotrya japonica Japanese Medlar/Loquat Ficus carica Common Fig Fraxinus americana White Ash Ginkgo biloba Ginkgo Gleditsia triacanthos var. inermis Thornless Honeylocust Lagerstroemia indica Crapemyrtle Liquidambar styraciflua American Sweet Gum Magnolia x soulangeana Saucer Magnolia Myrica cerifera Bayberry Nyssa sylvatica Blackgum Oxydendrum arboreum Sourwood, Sorrel Tree Pinus palustris Long-Leaf Pine Pinus thunbergii Black Pine Prunus serrulata Japanese Cherry Prunus x yedoensis Yoshino Cherry Quercus alba White Oak Quercus falcata Southern Red Oak Quercus laurifolia Laurel Oak Quercus nigra Water Oak Quercus phellos Willow Oak Quercus virginiana Live Oak Ground Cover Ajuga reptans Ajuga, Bugleweed Cotoneaster dammeri Bearberry Contoneaster Hypericum calycinum St. John’s Wort, Aaron’s Beard Juniperus conferta Shore Juniper Juniperus horizontalis Creeping Juniper Liriope muscari Liriope Ophiopogon japonicus Mondo Grass/Dwarf Lilyturf Santolina chamaecyparissus Cotton Lavender Teucrium chamaedrys Wall Germander Vinca minor Common Periwinkle COMMON EXAMPLES OF NATIVE SPECIES Canopy Trees Fagus grandifolia American beech Acer rubrum Red Maple Pinus taeda Loblolly pine Betula nigra River Birch Diospyros virginiana Common Persimmon Nyssa sylvatica Blackgum Pinus palustris Long-Leaf Pine Quercus alba White Oak Quercus falcata Southern Red Oak Quercus laurifolia Laurel Oak Quercus nigra Water Oak Quercus phellos Willow Oak Quercus virginiana Live Oak Understory Trees Cercis Canadensis Redbud Oxydendrum arboreum Sourwood, Sorrel Tree Cornus florida Dogwood Ilex opaca American Holly Aesculus pavia Red Buckeye Amelanchier arborea Downy Serviceberry Carpinus caroliniana Ironwood Halesia carolina Carolina Silverbell Shrubs Ilex vomitoria Yaupon Holly Myrica cerifera Southern Waxmyrtle Fothergilla gardenii Dwarf fothergilla Callicarpa americana American beautyberry Cephalanthus occidentalis Buttonbush Clethra alnifolia Sweet pepperbush Ilex glabra Inkberry Ilex verticillata Winterberry Itea virginica Virginia sweetspire Viburnum dentatum Arrowwood Viburnum nudum Possumhaw Groundcover Carex glaucescens Southern waxy sedge Carex grayi Gray’s sedge Chasmanthium latifolium River Oaks Muhlenbergia capillaris Pink muhly grass Panicum virgatum Switchgrass Schizachyrium scoparium Little bluestem Antennaria plantaginifolia Pussytoes Mitchella repens Partridgeberry Vaccinium crassifolium Creeping blueberry COMMON EXAMPLES OF INVASIVE SPECIES Trees Ailanthus altissima Tree-of-Heaven Albizia julibrissin Mimosa Melia azedarach Chinaberry Paulownia tomentosa Princess Tree Pyrus calleryana Callery 'Bradford' Pear Sapium sebiferum Chinese Tallow Tree Shrubs Berberis thunbergii Japanese Barberry Elaeagnus umbellata Autumn Olive Elaeagnus angustifolia Russian Olive Elaeagnus pungens Thorny Olive Lespedeza bicolor Bicolor Lespedeza Ligustrum japonicum Japanese Privet Ligustrum sinense Chinese Privet Ligustrum vulgare Common Privet Berberis bealei Oregon Grape Rosa multiflora Multiflora Rose Vines Ampelopsis brevipedunculata Porcelain-berry Celastrus orbiculatus Oriental Bittersweet Clematis terniflora Sweet Autumn Virginsbower Euonymus fortunei Winter Creeper Hedera helix English Ivy Ipomoea quamoclit Cypressvine Morningglory Lonicera japonica Japanese Honeysuckle Pueraria lobata Kudzu Wisteria sinensis Chinese Wisteria Wisteria floribunda Japanese Wisteria NATIVE TREES IN HIGHWAY 421 AREA These tree species will meet the requirements of Unified Development Ordinance Section 5.4.6.D. Preferred (should be used when possible) Magnolia grandiflora Southern Magnolia Pinus palustris Longleaf Pine Pinus taeda Loblolly Pine Quercus laevis Turkey Oak Quercus laurifolia Laurel oak Other Native Species (may be used when necessary) Acer rubrum Red Maple Carya glabra Pignut Hickory Carya pallida Sand Hickory Chionanthus virginicus Fringe Tree Juniperus viginiana Eastern Red Cedar Nyssa sylvatica Blackgum Prunus caroliniana Carolina Cherry Laurel Quercus alba White Oak Quercus falcata Southern Red Oak Quercus geminata Sand Live Oak Quercus stellata Post Oak Quercus virginiana Live Oak Page 1 of 38 PLOT SAMPLING METHODOLOGY FOR TREE INVENTORY This sampling methodology was outlined by James D. Gregory, Ph.D., CPSS, PWS for conducting an inventory of regulated trees as defined by the New Hanover County Unified Development Ordinance in October 2022. INTRODUCTION Rather than a map of all regulated trees, this methodology is designed to provide statistically valid data on the numbers and distribution across a tract of documented trees plus mapped locations of significant and specimen trees. An inherent assumption of sampling schemes for various types of forest inventory is that an inventory of a small percentage of the area of the forest stand provides an estimate of the desired parameters totaled over the stand. Such estimates are quite adequate for forest management planning, offering timber for sale and other potential objectives of a forest landowner. A sampling methodology is also suitable for the tree retention requirements of the UDO and will expand the numbers of potential contractors for conducting tree inventories because many environmental and forestry consulting firms have the equipment and field personnel needed to conduct the inventory. TERMINOLOGY 1. Forest stand: is a forested area in which the composition of the forest in regard to tree species present and the sizes and ages of the trees are relatively uniform. When planning an inventory of a forested tract, each stand must be considered separately. 2. DBH: is the tree diameter at breast height or 4.5 feet above the ground. 3. Global Positioning System (GPS), also often referred to as Global Navigation Satellite System (GNSS): is the system of satellites and ground based equipment that can be used to determine horizontal locations to high accuracy. Accuracy of a hand held GPS unit is related to a. The electronics of the unit b. The number of satellites that the unit can lock onto at one, and c. The capability of the unit to access ground based stations used to improve accuracy. The specified and confirmed locational accuracy of hand held GPS units is an important issue when used under a forest canopy because the tree canopy limits the number of satellites that the unit can “see.” 4. Geographic Information System (GIS): is computer graphics software that is used to create various types of maps and conduct various analyses of the characteristics of terrain. GIS maps can be printed directly from the software, converted to pdf format or converted to the format of computer-aided design (CAD) software used by engineers and architects. Page 2 of 38 5. Sampling intensity: is the total area of sample plots as a percent of the area of the forest stand to be inventoried. A sampling intensity of 10% is adequate for the tree inventory requirements of the UDO. 6. Tall the trees: for documented trees, tally means to record in a data sheet or field computer the number of trees by species within a designated dbh class in the plot. For significant and specimen trees, tally means to record the species, dbh, and coordinates of each tree. CONTRACTOR REQUIREMENTS 1. Personnel who: a. Are skilled in the use of GIS or CAD for mapping and terrain analysis, b. Are skilled in the use of GPS to determine the horizontal locations of plot centers and specific trees and to confirm accuracy of the instrument, and c. Can accurately identify the species (common and scientific names) of all native and naturalized nonnative trees that are present in a forest stand in New Hanover County. 2. GPS equipment that has horizontal error in the open of no greater than ± 1. 0 foot and under a forest canopy of no greater than ± 3.0 feet. 3. GIS or CAD software suitable for designing the sampling scheme and creating maps from the GPS data. TREE INVENTORY METHODOLOGY ESTABLISH PLOT CENTERS A sampling intensity of 10% of the area of the forest stand will be achieved with a square grid of 0.10 acre circular lots that have a radius of 37.2 feet, one plot per acre. With the tract boundary depicted accurately to scale in GIS or CAD, map plot centers in rows with 208.7 feet between plot centers in each row and 208.7 feet between plots in adjacent rows. That process divides the tract into 1.0 acre square blocks with the 0.10 acre circular sample plot at the center of each block. The figure below is an example of a 43.8 acre tract with 44 plots indicated by the dots as plot centers. The dotted lines indicate the square acre represented by each sample plot. The row of five plots on the eastern edge of the tract is somewhat closer to the next line of plots than 208 feet but far enough inside the tract boundary that the eastern edge of each plot is inside the boundary. The GPS unit is then used to navigate to the plot centers for collection of tree inventory data associated with each plot. Page 3 of 38 TREE INVENTORY DATA COLLECTION At each plot center, measure the distance to the edge of the circular plot at 8 radii and mark the plot boundary with flagging tape. Then tally the documented trees in 2-inch dbh classes between the minimum required dbh and the minimum dbh for significant trees. Next tally the significant and specimen trees that are within the plot and within the approximate area of the 1-acre section represented by the plot. Mark all significant and specimen trees with flagging tape or tree marking pain to avoid double tallying and for ease of locating them in the future. Page 4 of 38 TREE INVENTORY REPORT A report of the tree inventory will include: 1. A GIS or CAD map that includes the tract boundary and icons with plot numbers for the plot centers plus icons with tree numbers for the significant and specimen trees. All coordinate data will be in NC State Plane Coordinates, often referred to as the NC Grid System and conform to NAD 83 (2011). 2. A data report that includes: a. Contractor company and contact information b. Date(s) of field data collection c. Lists of significant and specimen trees that include the tree number, common and scientific names of the species, dbh, and coordinates d. Data table of tallied documented trees by species, including common and scientific names and dbh class i. Tree data for each plot and coordinates of the plot center ii. Tree data totals for the tract e. Note condition of any significant or specimen tree that has substantial crow or bole damage, heart rot or other issues that make the tree unsuitable for preservation 3. Notes: Provide pertinent information about the tract that may be useful to the land owner and to the county officials if/when a development on the tract is contemplated. Page 5 of 38 BASAL AREA MEASUREMENT METHODOLOGY Page 6 of 38 APPENDIX The following section is to serve as a guide to promote the health and longevity of trees, shrubs and other vegetation used for various purposes, including requirements as described in the Unified Development Ordinance. Examples and recommendations are from the Tree Care Industry Association A300 tree care practice guide and the Urban Tree Foundation. The best practices and guidelines that follow solely act as recommendations to promote property tree and plant installation, and maintenance in order to reduce premature death, or stunted growth. This is especially important for example, with vegetation used in buffer yards that are required to be a specific height within the first year in order to meet screening requirements. For additional information or for situations not presented here, please contact the New Hanover County Agricultural Extension Service or the North Carolina Department of Agriculture. SOIL PREPERATION The quality of soil and its preparation will directly affect the health and longevity and rate of growth of the plants and trees planted in soil that is appropriate for the species or is amended properly to accommodate the vegetation that is needed. A good first step is to conduct a soil analysis. Proper soil preparation can help control moisture reducing the cost of irrigation, help with drainage that can mitigate stormwater runoff, and promote nutrient holding that encourages strong root development. Some soil preparations include: • Changing/Balance soil pH o It is easier to plant vegetation adapted to existing soil pH then change the pH o High alkaline soils cannot be permanently corrected by practical means. o Lower pH with ammonium sulfate, sulfur, aluminum sulfate or sulfuric acid • Improving drainage o Direct water using berms or swales o Divert water away from existing trees in order to not “flood them” o Use perforated pipe under areas where gravel is used to improve drainage • Improve compacted soils o Use a coring machine to help air and water infiltrate areas with compact soil o Trench around plantings (vertical mulching) and then backfilling with soil • Adding fill o Mix existing soil with any new top fill soil brought onto site o Use soil with a similar texture or coarser and blend by tilling o Use plats with high wet site tolerances in low areas of the site • Mitigating soil salt contamination o Soils with high in sodium pose a risk to plant health. Gypsum or sulfur can be used to modify the soil. o Salt can be leached naturally with excess water Page 7 of 38 TREE PLANTING INSTRUCTIONS Along with soil preparation, following proper planting techniques and maintenance will ensure healthy, long lived vegetation as well as effect the rate of growth. The following recommendations include general planting details, and plantings in planters, like for parking lots. Some general practices include: • The planting hole should be at least twice as wide as the root ball. • The depth of the planting hole should be about two inches less than the bottom of the root system. Do not dig deeper than the root ball. • The side walls should be sloped at a 45-degree angle. • Remove any strapping, wire, plastic or paper and remove the top one-half (1/2) of any burlap/fabric or wire basket from the root ball. • Remove smaller kinked or girdling roots. • Fill 1/3 of the hole and pack soil around the base of the root ball. • Fill the remainder of the hole and carefully pack the soil to eliminate air pockets. • Form a shallow saucer or much no more than four inches to the outside edge of the root ball. Leave about a six-inch gap between mulch and the tree trunk. The figure below includes some general guidelines for planting in existing soil. Page 8 of 38 The figure below includes some general guidelines for planting in poorly drained soil. Page 9 of 38 STAKING In certain situations, staking may be necessary to provide trees additional support in order to remain upright and secure until the root system has developed anchoring the tree to the ground. Traditional staking utilizes ropes or wires wrapped around the tree and secured to posts. Typically, this support style is removed after the first year. A preferred method by arborists and tree advocates alike and one that has been tested, proven to be safe, and provide the most security is the “staple” technique. The staple technique requires four 2x2 piece of wood to be driven into the ground vertically at the edge of the root ball. Two horizontal 2x2 pieces of wood are connected to the vertical pieces creating U-shape or “staple”. Page 10 of 38 STAKING CONTINUED The figure below includes some general guidelines for tree staking using two posts. Three posts may also be needed depending on the overall rigidity of the tree at planting. A third post may also be necessary in areas susceptible to high wind gusts or during seasons that frequent strong storms. Page 11 of 38 PLANTERS (ROOT BARRIERS) For landscaping situations like parking lots, buffer yard or street yard where planters are necessary, the following guidelines are recommended. Parking lots are areas where soils have been graded and compacted to ensure stability of the ground prior to paving. While this is good for the long term quality in pavement, it is not for vegetation that is required in parking lot islands and perimeters. In these situations, planting areas should be tilled to loosen soils to promote healthy root development. Trees can grow very well in long planting strips in parking lots. Where applicable these strips can be combined with planting islands to create more contiguous soil space. Additionally, planting trees in clusters or larger spaces will result in healthier trees. It is not recommended to plant large maturing trees in small parking islands. For situations that require small islands as a requirement in the Unified Development Ordinance consult the New Hanover Cooperative Extension for recommendations on tree species. The figure below includes some general guidelines for when planters needing root barriers are necessary in parking lot islands. Page 12 of 38 PLANTERS (ROOT BARRIERS) CONTINUTED The figure below includes some general guidelines for when planters needing root barriers are necessary in parking lot perimeters. Page 13 of 38 SHURB PLANTING The figure below includes some general guidelines for planting shrubs. INCLUDE LLANGUE FROM FOUNDATION PLANTINGS 5.4.7 Page 14 of 38 GROUNDCOVER PLANTING Groundcover maintenance is important is it addresses numerous issues that can arise if not properly maintained. INCLUDE LLANGUE FROM FOUNDATION PLANTINGS 5.4.7 The figure below includes some general guidelines for planting groundcover. MULCHING Mulching can be used around the root ball in order to control weeds and retain soil moisture. A general recommendation is to apply only a one-inch-thick layer of much. Excess mulch can actually repel water or absorb water meant for the root ball. Too much mulch can become dens for rodents and lead to stem girdling. Page 15 of 38 TREE MAINTENANCE (PRUNING) Pruning is not only vital for the overall health of trees and landscaping materials but it is also important for safety and aesthetic reasons. The following practices and pruning standards are from the American National Standards for Tree Care Operations, ANSI A300 manual. For more information, please see the Tree Care Industry Association website. • Not more than 25 percent of the foliage of a branch should be removed within an annual growing season. The percentage and distribution of foliage to be removed shall be adjusted according to the plant’s species, age, health, and site. • Not more than 25 percent of the foliage of a branch or limb should be removed when it is cut back to a lateral. That lateral should be large enough to assume apical dominance. • Interior branches shall not be stripped out i.e. lion-tailed. • Pruning cuts larger than 4-inches in diameter should be avoided unless otherwise directed. • Pruning cuts shall be made outside the branch bark ridge. Flush cuts are not acceptable. • Where the length of branches must be reduced, cuts may be made only to lateral Page 16 of 38 Page 17 of 38 TREE TRANSPLANTING In situation where there are significant trees and or specimen trees that will be transplanted as an option for mitigation as stated in section 5.3.7 Mitigation of the Unified Development Ordinance, the following are recommendations to promote a successful transplant and ensure the tree will thrive in its new location. •