4.1 Existing Tree Removal
▶ Trunk and Branch Removal: Remove all existing trees indicated by the drawings as requiring removal, in a manner that will not damage adjacent trees or structures or compacts the soil. Remove trees that are adjacent to trees or structures to remain, in sections, to limit the opportunity of damage to adjacent crowns, trunks, ground plane elements and structures. Do not drop trees with a single cut unless the tree will fall in an area that is not included in the Tree and Plant Protection Area. No trees slated to be removed within 50 feet of the Tree and Plant Protection Area shall be pushed over or up-rooted using a piece of grading equipment. Protect adjacent paving, soil, trees, shrubs, ground cover plantings and understory plants that will remain from damage during all tree removal and construction operations. Protection shall include the root system, trunk, limbs, and crown from breakage or scarring, and the soil from compaction.
▶ Stump Removal: Remove stumps and the immediate root plate from any trees cut down. Grind the trunk base and large buttress roots to a depth of the largest buttress root, or at least 18 inches below the top most roots, which ever is less, and over the area of three times the diameter of the trunk (DBH).
▶ In areas where a stump is in a planting bed or lawn, remove all woodchips and backfill stump holes with planting soil (see 2.6), in maximum of 12 inch layers and compact to 80 - 85% of the maximum dry density.
▶ For trees where the stump will fall under new paved areas, grind the roots to a total depth of 18 inches below the existing grade until there is less than approximately 20% wood visible. Remove all wood chips produced by the grinding operation and back fill in 8 inch layers with acceptable soil (see x.x) compacted to 95% of the maximum dry density.
4.2 Existing Tree Protection Area
▶ Defined: An area surrounding individual trees, groups of trees, shrubs, or other vegetation to be protected during construction, and defined by a circle centered on the trunk of each tree, with a radius equal to the clown dripline. Tree protection fencing should be installed prior to any construction activity at the site, including utility work, grading, storage of materials, or installation of temporary construction facilities. Bulk materials such as soil or aggregate should never be stored within the Tree and Plant Protection Area. The Tree and Plant Protection Areas are indicated on the landscape plan if they are recommended for your project.
▶ Protection Fence:
▶ Fencing for Residential and Commercial Areas: Heavy-duty orange plastic mesh fencing fabric 48 inches wide should be sufficient for most projects. The plastic mesh is to be attached to metal “U” or “T” posts driven into the ground of sufficient depth to hold the fabric solidly in place with out sagging. The fabric shall be attached to the post using attachment ties of sufficient number and strength to hold up the fabric without sagging.
▶ Fencing for Urban Areas: A more robust option for areas that might have conflicts between tree preservation and other work tasks, is a 6-feet tall metal chain link fence set in metal frame panels on movable core drilled concrete blocks of sufficient size to hold the fence erect in areas where existing paving is to remain.
▶ Gates: You should allow for access into the Tree Protection Area for either of the above options. Depending on the characteristics of your site, you may want to provide a lockable gate.. Gates should be a minimum 3 feet wide.
▶ Signage: Provide signage to notify others of the protected area. A good template to go by is a heavy-duty 8.5 x 11" cardboard sign with a white colored background, and black 2-inch high or larger letters block letters. The tree protection sign may read “Tree and Plant Protection Area- Keep Out” and spaced along the fence every 50 feet.
▶ Mulch Installation: For all areas within the Tree and Plant Protection area, provide a minimum of 5 inches of Wood Chips or Mulch (see x.x):
▶ Areas where foot traffic or storage of lightweight materials is anticipated to be unavoidable, provide a layer of Filter Fabric under the 5 inches of Wood Chips or Mulch.
▶ Areas where occasional light vehicle traffic (skid steer) is anticipated to be unavoidable, provide a layer of Geogrids under 8 inches of Wood Chips or Mulch.
▶ Areas where heavy vehicle traffic is unavoidable provide a layer of Geogrids under 8 - 12 inches of Wood Chips or Mulch and a layer of matting over the Wood Chips or Mulch.
▶ Trunk Protection: Protect the trunk of each tree to remain by covering it with a ring of 8-foot 2"x 6" planks loosely banded onto the tree with 3 steel bands. Staple the bands to the planks as necessary to hold them securely in place. Trunk protection should not be kept in place longer than 12 months.
▶ Root Pruning: Prior to any excavating into the existing soil grade within 25-feet of the limit of the Tree and Plant Protection Area or trees to remain, root prune all existing trees to a depth of 24-inches below existing grade in alignments following the edges of the Tree and Plant Protection Area. Using a rock saw, chain trencher or similar trenching device, make a vertical cut within 2-feet of the limit of grading. After completion of the cut, make clean cuts with a lopper, saw or pruner to remove all torn root ends on the tree side of the excavation, and backfill the trench immediately with existing soil, filling all voids.
▶ Maintenance Within the Tree Protection Area: Ensure that adequate water is provided to all plants to be preserved during the entire construction period. This is defined by the amount necessary for a plant to not wilt. Keeps the area free of weeds during construction. Monitor all plants to remain for disease and insect infestations during the entire construction period. You may seek guidance from a professional or online resources to provide any disease and insect control required to keep the plants in a healthy state.
▶ Work Within the Tree Protection Area: In general, demolition and excavation within the drip line of trees and shrubs shall proceed with extreme care either by the use of hand tools, directional boring and or Air Knife excavation where indicated or with other low impact equipment that will not cause damage to the tree, roots or soil. If excavation for footings or utilities is required within the Tree and Plant Protection Area, air excavation tool techniques should be used where practical.
4.3 Existing Tree Pruning
▶ Defined: This is a horticultural and silvicultural practice involving the selective removal of certain parts of a tree, such as branches, buds, or roots.
▶ What to Prune: Prune all dead or hazardous branches larger than 2 inch in diameter from all existing trees to remain.
▶ Where to Prune: Prune any low, hanging branches and vines from existing trees and shrubs that overhang walks, streets and drives, or parking areas as follows:
▶ Walks - within 8 feet vertically of the proposed walk elevation.
▶ Parking areas - within 12 feet vertically of the proposed parking surface elevation.
▶ Streets and drives - within 14 feet vertically of the proposed driving surface elevation.
▶ When to Prune: Prune trees within 6 months of the date you estimate your landscape project to be complete.
4 Existing Plants