A. Contractor shall provide product data for each type of product indicated.

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1 SELECTIVE TREE AND SHRUB REMOVAL AND TRIMMING SECTION 1 GENERAL 1.1 SUMMARY A. This section includes general protection and pruning of existing trees and plants that are affected by execution of the Work, whether temporary or permanent construction. 1.2 DEFINITIONS A. The Protection Zone shall be defined as the area surrounding individual trees or groups of trees to be protected during construction, and is further defined by a circle concentric with each tree with a radius 1.5 times the diameter of the drip line unless otherwise indicated. 1.3 SUBMITTALS A. Contractor shall provide product data for each type of product indicated. B. Contractor shall provide samples for each type of organic mulch in sealed plastic bags labeled with composition of materials by percentage of weight, protection zone fencing, and protection zone signage. C. Contractor shall provide a written Tree Pruning Schedule detailing scope and extent of pruning of trees to remain that interfere with or are affected by construction. D. Contractor shall provide certification from an arborist, certifying that trees indicated to remain have been protected during construction according to recognized standards and that those trees were promptly and properly treated and repaired when damaged. E. Contractor shall provide maintenance recommendations from an arborist, for care and protection of trees affected by construction during and after completing the Work. F. Contractor shall provide documentation of existing trees and plantings indicated to remain, which shall establish preconstruction conditions that might be misconstrued as damage caused by construction activities. 1.4 QUALITY ASSURANCE A. Arborist shall be an arborist certified by ISA, be licensed arborist in the jurisdiction where Project is located, and be a current member of ASCA, or registered Consulting Arborist as designated by ASCA. B. Contractor shall conduct pre-installation conference at the project site. American States Utility Services Selective Tree and Shrub Removal and Trimming

2 1.5 PROJECT CONDITIONS A. The following practices are prohibited within protection zones: i. Storage of construction materials, debris, or excavated material. i iv. Parking vehicles or equipment. Foot traffic. Erection of sheds or structures. v. Impoundment of water. vi. v Excavation or other digging unless otherwise indicated. Attachment of signs to or wrapping materials around trees or plants unless otherwise indicated. B. Contractor shall not direct vehicle or equipment exhaust toward protection zones. C. Contractor shall prohibit heat sources, flames, ignition sources, and smoking within or near protection zones and organic mulch. SECTION 2 MATERIALS 2.1 MATERIALS A. Topsoil shall be: i. Natural or cultivated top layer of the soil profile or manufactured topsoil; containing organic matter and sand, silt, and clay particles; friable, pervious, and black or a darker shade of brown, gray, or red than underlying subsoil; reasonably free of subsoil, clay lumps, gravel, and other objects more than 1 inch in diameter; and free of weeds, roots, and toxic and other non-soil materials. Stockpiled topsoil from areas cleared and grubbed or stripped from locations shown on Drawings or locations stripped as directed by the Utility. B. Organic Mulch shall be wood and bark chips, free from deleterious materials. C. Protection-Zone Fencing shall be fencing fixed in position and may be previously used materials when approved by the Utility. i. Plastic Protection-Zone Fencing shall be plastic construction fencing constructed of high-density extruded and stretched polyethylene fabric with 2-inch maximum opening in pattern and supported by tubular or T- American States Utility Services Selective Tree and Shrub Removal and Trimming

3 shape galvanized-steel posts spaced not more than 8 feet apart, and shall be non-fading high-visibility orange in color. The height of the fencing shall be 4 feet. D. Protection-Zone Signage shall be shop-fabricated, rigid plastic or metal sheet with attachment holes pre-punched and reinforced; and legibly printed with non-fading lettering. SECTION 3 EXECUTION 3.1 EXAMINATION AND PREPARATION A. Contractor shall examine the site to verify that temporary erosion and sedimentation control measures are in place. Contractor shall verify that flows of water redirected from construction areas or generated by construction activity do not enter or cross protection zones. Erosion and sedimentation control measures are to be as specified in Division Erosion and Sedimentation Control. B. Contractor shall protect tree root systems from damage caused by runoff or spillage of noxious materials while mixing, placing, or storing construction materials. Contractor shall protect root systems from ponding, erosion, or excessive wetting caused by dewatering operations. C. Contractor shall mulch areas inside protection zones and other areas indicated with 4-inch average thickness of organic mulch. Do not place mulch within 6 inches of tree trunks. 3.2 PROTECTION ZONES A. Contractor shall install protection-zone fencing along edges of protection zones in a manner that will prevent people from easily entering protected area. B. Contractor shall install protection-zone signage in visibly prominent locations in a manner approved by the Utility. C. Contractor shall repair or replace trees, shrubs, and other vegetation indicated to remain or be relocated that are damaged by construction operations, in a manner approved by the Utility. D. Contractor shall maintain protection-zone fencing and signage in good condition as acceptable to the Utility and remove when construction operations are complete and equipment has been removed from the site. 3.3 EXCAVATION A. Contractor shall excavate at edge of protection zones and for trenches indicated within protection zones according to requirements in Section Excavation Trenching and Backfilling. American States Utility Services Selective Tree and Shrub Removal and Trimming

4 B. Where utility trenches are required within protection zones, the Contractor shall hand excavate under or around tree roots or tunnel under the roots by drilling, auger boring, or pipe jacking. Contractor shall not cut main lateral tree roots or taproots; cut only smaller roots that interfere with installation of utilities. Cut roots as required for root pruning. C. Contractor shall not allow exposed roots to dry out before placing permanent backfill. 3.4 ROOT PRUNING A. Contractor shall prune roots that are affected by temporary and permanent construction. Prune roots as follows: i. Cut roots manually by digging a trench and cutting exposed roots with sharp pruning instruments; do not break, tear, chop, or slant the cuts. Do not use a backhoe or other equipment that rips, tears, or pulls roots. i Temporarily support and protect roots from damage until they are permanently covered with soil. Cover exposed roots with burlap and water regularly. iv. Backfill as soon as possible according to requirements in Section Excavation Trenching and Backfilling. B. Contractor shall prune roots at the edge of Protection Zone by cleanly cutting all roots to the depth of the required excavation. C. Contractor shall prune roots within Protection Zone as follows: i. Clear and excavate by hand to the depth of the required excavation to minimize damage to root systems. Use narrow-tine spading forks, comb soil to expose roots, and cleanly cut roots as close to excavation as possible. 3.5 CROWN PRUNING A. Contractor shall prune branches that are affected by temporary and permanent construction. Prune branches as follows: i. Prune trees to remain to compensate for root loss caused by damaging or cutting root system. Provide subsequent maintenance during Contract period as recommended by arborist. Prune trees according to ANSI A300 Part 1 and the following: a. Cut branches with sharp pruning instruments; do not break or chop. American States Utility Services Selective Tree and Shrub Removal and Trimming

5 b. Do not apply pruning paint to wounds. B. Contractor shall chip removed branches and dispose of all chipped material offsite. 3.6 REGRADING A. Where new finish grade is indicated below existing grade around trees, Contractor shall slope grade beyond the protection zone. Contractor shall maintain existing grades within the protection zone. B. Where new finish grade is indicated above existing grade around trees, Contractor shall slope grade beyond the protection zone. Contractor shall maintain existing grades within the protection zone. C. Where existing grade within the Protection Zone is 2 inches or less below elevation of finish grade, Contractor shall fill with topsoil. Contractor shall place topsoil in a single uncompacted layer and hand grade to required finish grade elevations. 3.7 FIELD QUALITY CONTROL A. Contractor shall engage a qualified arborist to direct plant-protection measures in the vicinity of trees, shrubs, and other vegetation indicated to remain and to prepare inspection reports. 3.8 REPAIR AND REPLACEMENT A. Contractor shall repair or replace trees, shrubs, and other vegetation indicated to remain or be relocated that are damaged by construction operations, in a manner approved by the Utility. i. Have arborist perform the root cutting, branch pruning, and damage repair of trees and shrubs. i iv. Treat damaged trunks, limbs, and roots according to arborist's written instructions. Perform repairs within 24 hours. Replace vegetation that cannot be repaired and restored to full-growth status, as determined by the Utility. END OF SECTION American States Utility Services Selective Tree and Shrub Removal and Trimming

Van Buren Bridge Project. IFB # VBB Attachment K PROVISIONS DEPARTMENT OF PUBLIC WORKS FOR CITY OF FALLS CHURCH CITY PROJECTS

Van Buren Bridge Project. IFB # VBB Attachment K PROVISIONS DEPARTMENT OF PUBLIC WORKS FOR CITY OF FALLS CHURCH CITY PROJECTS Van Buren Bridge Project IFB #0721-17-VBB GENERAL TREE & LANDSCAPE PROVISIONS CONSTRUCTION SPECIFICATIONS PROJECTS DEPARTMENT OF PUBLIC WORKS FOR CITY OF FALLS CHURCH CITY PROJECTS DEPARTMENT OF PUBLIC