PART 1 GENERAL

1.01 SECTION INCLUDES

A. All labor, materials, equipment, transportation and services pertaining to the construction of tree protection fencing systems including but not limited to the following:

1. Tree Protection Fencing.

2. Tree Protection Signage.

3. Wood Chips.

1.02 RELATED SECTIONS

A. 02 40 00 – Demolition.

B. 31 11 00 – Site Preparation.

C. 31 22 00 – Grading.

D. 32 84 00 – Irrigation.

E. 32 91 00 – Soil Preparation.

F. 32 92 00 – Turf and Grasses.

G. 32 93 00 – Plants.

1.03 REFERENCE STANDARDS

A. International Society of Arboriculture – Arborists' Certification Study Guide. 1.04 ADMINISTRATIVE REQUIREMENTS A. Refer to discipline drawings for additional requirements.

B. In the event of conflicting requirements between discipline notes and the requirements in this specification, the most stringent requirements apply.

C. It is the sole responsibility of the Contractor to provide all required notifications, submittals, and information outlined in this specification in a timely manner, without reliance on requests or reminders from the Design Team, Owner’s Authorized Representative, Owner, or other parties. Failure to comply with these requirements shall not relieve the Contractor of any obligations under the contract, and any resulting delays or additional costs shall be the Contractor’s responsibility.

1.05 PROVISIONS

A. Do not store construction materials debris excavated material, permit vehicular traffic or repeated foot traffic in protected areas as indicated by the Project Arborist.

B. No construction trailers shall be placed within the tree protection areas; no other use of the tree protection area is permitted

C. Provide protection of existing root systems of trees from dumping of chemically injurious material or liquids, and continual puddling of running water.

D. Review method of tree protection to be implemented with the Landscape Architect prior to commencement of work.

E. This specification shall be applied concurrently and in conjunction with other plant material protection measures herein described and specified.

1.06 SUBMITTALS

A. Tree and Landscape Protection Plan: Prior to any site disturbance, submit for Owner's Authorized Representative approval a “Tree and Landscape Protection Plan” developed in consultation with the Project Arborist for all trees, vegetation indicated to remain. Submit the name and credentials of the Project Arborist with the plan.

1.07 DEFINITIONS

A. Critical Root Zone (CRZ): Is the area around a tree where the minimum amount of roots that are biologically essential to the structural stability and health of the tree are located.

B. Certified Arborist: Synonymous with Project Arborist. An arborist certified by the International Society of Arboriculture.

C. Dripline: The dripline of a tree is the area beneath the farthest reach tree's canopy away from the trunk.

D. Tree Protection Zone (TPZ): Is an area defined during site development, where construction activities and access are limited to protect the tree(s) and soil from damage and to sustain tree health and stability during construction. This zone is intended to protect root systems, soils, and the aboveground parts of trees.

1.08 CONTRACTOR RESPONSIBILITY

A. Contractor to assume all landscape shall be protected, unless indicated to be removed in the Contract Documents, and shall be responsible for all damaged and/or disturbance within the TPZ of trees indicated to remain such as, cutting or skinning of roots, skinning or bruising of bark, compaction of root zones, and breaking of branches.

1. Damage and/or disturbance which can be remedied by corrective maintenance shall be immediately repaired by the Contractor upon written notice by the Owner's Authorized Representative.

a. The Contractor shall employ a Project Arborist to repair damage to trees.

2. Trees or shrubs which are injured or irreparably damaged shall be replaced by the Contractor with new trees or shrubs of the same size and type at no expense to the Owner.

3. If replacement of damaged trees is determined impracticable by the Owner’s Authorized Representative, the full replacement cost shall be borne by the Contractor at values based upon the square inches of cross sectional area of trunk measured at four (4) feet above grade, in accordance with the following criteria:

a. $75.00/square inch for trees less than or equal to six (6) inch diameter.

b. $50/square inch for trees greater than six (6) inch and less than eighteen (18) inch diameter

c. $40.00/square inch for trees greater than or equal to eighteen (18) inch diameter.

B. Trees or shrubs which require removal and/or replacement due to damage by construction shall be removed to a depth of two (2) feet below grade and include the refilling and repair of the ground surface, with costs to be borne by the Contractor.

C. Protection and maintenance shall include, but not be limited to, replacement of damaged protection fencing; aeration of compacted soils; control of temporary irrigation water runoff; pruning and treatment of damaged roots, limbs, and branches’ and replacement of wood chips within tree protection areas.

D. Site damage and/or disturbance caused by the contractor outside the project site shall be repaired or replaced, and all costs shall be borne by the Contractor.

1. Repairs shall include, but are not limited to, pruning or removing damaged vegetation, replacement of damaged vegetation and/or lawn restoration, soil remediation to alleviate over-compaction, and temporary irrigation to establish new plantings.

PART 2 PRODUCTS

2.01 MATERIALS

A. Contractor to confirm Authority Having Jurisdiction (AHJ) minimum tree protection requirements. In the event of conflicting requirements between discipline notes and the AHJ, the most stringent requirements apply.

B. Tree Protection Fencing

1. Posts:

a. Material: Galvanized steel.

b. Size: 2 1/2" diameter.

c. Length: 8'.

2. Fencing:

a. Material: Galvanized wire mesh.

b. Size: 2" mesh.

C. Tree Protection Signage:

1. Material: Laminated or weatherproofed florescent yellow signage.

2. Size: 11"x17".

3. Attachment: Permanently secure signage along the fencing at twenty (20) foot intervals.

4. Text: Signage to read "TREE PROTECTION ZONE. KEEP OUT! TREES ENCLOSED BY THIS FENCE ARE TO BE RETAINED & PROTECTED. ANY INCURSION INTO THE PROTECTED AREA MUST BE APPROVED BY A PROJECT ARBORIST. FAILURE TO OBSERVE THESE CONDITIONS MAY LEAD TO FINES AND/OR PENALTIES."

D. Wood Chips

1. Material: Cedar wood chips free of fines.

2. Accessories:

a. Geotextile Fabric: Mirafi 140N or approved equal.

b. Landscape Staples: Vigoro Fabric and Garden Staples or approved equal.

PART 3 EXECUTION

3.01 ON-SITE PRE-INSTALLATION MEETING

A. Prior to on-site mobilization, the Contractor shall arrange a pre-installation meeting with the Authorized Owner’s Representative and the Project Arborist or Landscape Architect to identify and stake out all areas of trees, plants, and lawn that are to be protected or removed. The Contractor shall be responsible for all damage to landscape features that results from the failure to schedule and attend the pre-installation meeting.

3.02 SITE SURVEY

A. Inspect trees shown on plans to be protected, prior to the start of construction.

1. Existing root systems are to be located by air spading methodology prior to commencement of any type of work by the Project Arborist or Owner's Authorized Representative.

2. Document and photograph any unusual conditions as well as any trees in poor condition prior to construction.

3. Submit copies of documentation to the Project Arborist and Owner's Authorized Representative prior to beginning work.

4. The Project Arborist to verify conditions regarding tree protection with the Owner's Authorized Representative prior to any site disturbance.

3.03 GENERAL

A. Trees and shrubs indicated to remain within the Project site shall have protection fencing located along the TPZ.

B. When access is required within the TPZ, wood chips are to be installed over the area that will be accessed to mitigate soil compaction caused by regular foot traffic. If vehicular access is required within the TPZ, notify the Owner's Authorized Representative and coordinate with the Project Arborist or Landscape Architect on strategies for mitigating impacts.

C. All site work within the TPZ shall be performed by hand. However, the use of heavy equipment to perform work within the TPZ may be requested by the Contractor for approval by the Owner's Authorized Representative and Project Arborist or Landscape Architect. The Contractor shall perform approved heavy equipment work from angles and directions that minimize compaction to tree roots in the protection area.

D. All site work within the CRZ is not recommended and should be avoided if possible. Contact the Owner's Authorized Representative and Project Arborist or Landscape architect if site work is required within the CRZ. The use of heavy equipment to perform work within the CRZ is not allowed.

E. The Contractor shall utilize a Project Arborist to tie back all flexible limbs and overhead branches which may be damaged by the passage or activity of construction equipment.

F. Materials shall not be stored and equipment shall not be operated under the branches of existing trees which are to remain, except as approved by the Owner's Authorized Representative.

G. Protect root systems of trees, and adjacent (neighboring properties) shrubs, and ground covers from smothering, damage due to noxious materials in solution and from flooding, erosion, or excessive wetting.

H. Trees to be removed shall be clearly marked with construction flagging, tree marking paint, or other methods approved in advance by the Project Arborist.

3.04 TREE PROTECTION FENCING

A. Contractor to confirm AHJ minimum tree protection requirements. In the event of conflicting requirements between discipline notes and the AHJ, the most stringent requirements apply.

B. Protection fencing shall be secured to posts placed no further than ten (10) feet apart and shall be installed at the edge of the TPZ.

C. Signage designating the TPZ and penalties for violations shall be secure in a prominent location on each fence.

D. The following is prohibited within TPZ fencing or outside of development impact area

1. Ground disturbance or construction activity including:

a. Vehicle access

b. Equipment and material storage; including soils

c. Stockpiling

d. Structures

e. Impervious surfaces

f. Underground utilities

g. Excavation, fill, trenching or other work activities

E. Tree Protection Fencing shall be installed before any ground-disturbing activities including clearing, grading, or construction starts; and shall remain in place until final inspection.

3.05 DEMOLITION

A. The Project Arborist is to provide a scaled plan of exact locations of tree protection fencing prior to beginning work.

B. The Project Arborist or Owner's Authorized Representative is to be notified a minimum of Fortyeight (48) hours prior to the beginning of any type of demolition. The Owner's Authorized Representative is to visit the site periodically throughout the demolition process and document findings.

C. Protect existing trees to remain against unauthorized cutting, breaking, or skinning roots and branches, skinning, and bruising of bark. Where cutting is determined to be necessary, review conditions with Project Arborist before proceeding, and comply with directives of the Owner's Authorized Representative.

D. Demolition of existing buildings and asphalt removal is to occur with as little impact to existing trees as possible. Project Arborist to be on-site during excavation of building and asphalt within Thirty (30) feet for any of the trees that are to remain on site. Any condition thought to be detrimental to the long-term survival of the existing trees is to be immediately reported to the Owner's Authorized Representative.

E. Project Arborist is to oversee the pruning of branches of the existing trees in accordance with good horticultural practice to accommodate demolition to occur with no impacts and future scaffolding to occur.

3.06 DURING CONSTRUCTION

A. TPZ Maintenance:

1. The protection fencing shall not be moved, removed, or entered by equipment except under the direction of the Project Arborist or Owner’s authorized representative.

B. Storage of Material or Equipment:

1. The contractor shall not store materials or equipment within the TPZ.

C. Excavation within the TPZ:

1. Excavation with the TPZ shall be avoided if alternatives are available.

2. All excavation within the TPZ shall be performed by hand. However, the use of heavy equipment to perform work within the TPZ may be requested by the Contractor for approval by the Owner's Authorized Representative and Project Arborist or Landscape Architect. The Contractor shall perform approved heavy equipment work from angles and directions that minimize compaction to tree roots in the protection area.

3. All excavation within the CRZ is not recommended and should be avoided if possible. If excavation within the CRZ is unavoidable, the Project Arborist or Landscape Architect shall evaluate the proposed excavation to determine methods to minimize impacts to trees. This can include tunneling, hand digging, or other approaches. The use of heavy equipment to perform work within the CRZ is not allowed.

4. All construction within the TPZ shall be under the on-site technical supervision of the Owner's Authorized Representative, Project Arborist or Landscape Architect.

D. Tree Protection Inspection: The Project Arborist or Owner’s Authorized Representative shall monitor construction activities and progress, and provide written reports to the Owner at regular intervals

E. Final Report: After the project has been completed, the Project Arborist shall provide a final report that describes the measures needed to maintain and protect the remaining trees.

3.07 EXCAVATION AROUND TREES

A. Notify the Owner's Authorized Representative, Project Arborist or Landscape Architect a minimum of forty-eight (48) hours prior to any type of excavation work around existing trees. The Owner's Authorized Representative, Project Arborist or Landscape Architect will visit the site periodically during the excavation process and document findings.

B. Excavate around trees only in areas indicated by the Owner's Authorized Representative, Project Arborist or Landscape Architect.

C. Where trenching is required within tree protection areas, tunnel under or around roots by hand digging or boring. Do not cut main lateral roots or taproots; cut smaller roots, which interfere with installation of new work. Trench toward trunk of trees and tunnel under central root mass to avoid severing lateral roots on side of trench. Use narrow tine spading forks and comb soil to expose roots. Relocate roots in backfill areas wherever possible. The Owner's Authorized Representative, Project Arborist or Landscape Architect to be on-site to supervise any trenching or digging within the tree protection areas.

D. Do not allow exposed roots to dry out before permanent backfill is placed; provide temporary earth cover, or pack with peat moss and wrap with burlap. Water and maintain in moist condition until relocated and covered with backfill.

E. Water roots exposed as directed by the Project Arborist or Landscape Architect.

F. Backfill roots after inspection approval by the Project Arborist or Landscape Architect.

1. Backfill around root excavations only with clean imported topsoil free from materials detrimental to root growth.

2. Backfill to eliminate voids, utilize water to eliminate air voids in the soil. Do not compact manually as that may damage roots.

3. Water sufficient to settle topsoil and eliminate voids or air pockets around roots.

4. Allow for natural settlement of soil surface, and furnish and apply topsoil sufficient to bring to original finish grade after backfill settlement.

G. The Project Arborist or Landscape Architect is to notify the Owner's Authorized Representative immediately of any conditions that threaten survivability of protected trees or that affect the stability of the integrity of root systems.

3.08 GRADING AND FILLING AROUND TREES

A. Maintain existing grade within the drip line of trees unless otherwise indicated by the Project Arborist or Landscape Architect.

3.09 LANDSCAPING

A. The Owner's Authorized Representative, Project Arborist or Landscape Architect is to be notified a minimum of forty-eight (48) hours prior to any type of rototilling or trenching.

B. No rototilling or trenching is to occur within the drip lines of trees designated to be retained without the approval of the Owner's Authorized Representative, Project Arborist or Landscape Architect.

3.10 MAINTENANCE OF PROTECTIVE MEASURES

A. Maintain protective measures throughout the construction process.

1. Repair any alteration to protection measures throughout the construction process.

2. Repair or reinstall protective measures upon alteration. Alteration to the fence is to be completed only after receiving written authorization from the Owner's Authorized Representative, Project Arborist or Landscape Architect.

3. Monitor protective measures daily.

4. Pruning and/or repairs must be approved in advance and at completion by the Owner’s Authorized Representative after notification of Project Arborist or Landscape Architect.

5. The contractor is responsible for cost of repair caused by his actions or by actions of subcontractors.

3.11 CLEANING AND ADJUSTING

A. Remove fencing, barricades, and guards as required.

B. Remove debris and dispose of it in a legal manner.

END OF SECTION

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