ILLINOIS URBAN MANUAL PRACTICE STANDARD TREE PROTECTION In Highly Urbanized Areas with Existing Green and Gray Infrastructure Conflicts (each.) CODE 990B (Source: IN Drainage Handbook) NOTE: Only use Practice Standard Code the health and integrity of the tree 990B when there are green and gray resources on site. infrastructure conflicts and when adequate long-term monitoring of the trees exists. This standard MUST BE USED ONLY IN CONDITIONS WHERE PRACTICE CONSULTATION with a PROFESSIONAL APPLIES FORESTER or CERTIFIED ARBORIST. This standard shall be used in lieu of no DEFINITION local ordinance or in tandem with local tree protection ordinances. When The protection of individual trees from possible, IUM Practice Standard Code damage during construction operations 990A -TREE PROTECTION shall be in highly urbanized areas where there used instead of IUM Practice Standard are individual trees growing close to Code 990B. IUM Practice Standard gray urban infrastructure. Code 991- TREE PROTECTION- AUGERING Standard should be used in PURPOSE conjunction with this standard, as needed. The purpose of this practice is to reduce damage to and loss of individual trees This standard takes into consideration during construction by implementing trees next to roads and sidewalks where these pre- to post-construction tree there already exists an infrastructure protection procedures. Tree protection conflict that can be resolved without fencing around the Tree Protection compromise to either the green or gray Critical Root Zone (TPCRZ) as defined infrastructure. below along with other soil, root and tree protection measures shall be installed This practice applies on development with this standard in order to maintain sites that are highly urbanized, where 990B - 1 the green and gray infrastructure has be protected using the length of the been developed or has grown in close longest branch as the radius of the proximity and where there are individual circle. The second technique determines trees of importance that need to be CRZ by referring to Table 1 Guidelines preserved. Refer to IUM Practice for determining tree protection zone Standard Code 984 - TREE AND (TPZ) radius for healthy, structurally FOREST ECOSYSTEM sound trees per the International Society PRESERVATION for information on of Arboriculture (ISA) Best Management preserving stands of trees. Refer to IUM Practices for Managing Trees During Practice Standard Code 990A for TREE Construction. This method measures PROTECTION in Moderately Urbanized the diameter in inches at 4.5 feet above Areas to Open Spaces for information ground (DBH diameter breast height) in on tree protection in all other areas with combination with the trees age and trees. tolerance to construction. See Table 2 for Species Tolerance Ratings. CRITERIA The contractor shall use whichever LOCAL AUTHORITIES When working method affords the greatest protection within the boundary of a municipality, for the tree or whichever creates the local authorities such as the Urban larger CRZ area and then add an Forester, City Arborist, Municipal additional one foot to create the TPCRZ Forester or Horticulturist, or Public Works officials should be contacted to PROFESSIONAL ADVISEMENT IS determine locally enforced tree REQUIRED IN HIGHLY URBANIZED protection/preservation standards. AREAS. The TPCRZ is the area to be protected less the area in conflict with JULIE Before any work has begun, call the gray infrastructure. Any limited JULIE- (Joint Utility Locating Information space design protection measures shall for Excavators) at 800-892-0123 at least be made per the advisement of the local 48 hours prior to any work being done. Forestry Professionals and/or Certified Equivalent local authorities shall also be Arborist with tree protection training. contacted, where applicable. In situations where the green and gray DETERMINING THE TREE infrastructure can’t be protected in its PROTECTION CRITICAL ROOT ZONE entirety, the alternative plans must be (TPCRZ) Tree Protection starts with approved by the Professional Forester determining the TPCRZ or area where or Certified Arborist. IN HIGHLY the majority of roots are located and URBANIZED AREAS where such space where tree protection fencing should be for protecting the trees does not exist, a located. The TPCRZ is located one foot Professional Forester and/or Certified outside the Critical Root Zone (CRZ). Arborist must be consulted for any reduced Tree Protection or Fencing To determine the CRZ, one of the Standards. following two techniques shall be used. The first is by using the definition of FENCING Per IUM Standard Drawing CRZ or two feet outside the perimeter of IUM-690-B - TREE PROTECTION - the leaf canopy or drip line of the tree to FENCING, trees to be protected per the 990B - 2 approved construction plan or by local In HIGHLY URBANIZED AREAS, if foot ordinance shall be protected with or vehicular traffic or construction fencing around the Tree Protection activities cannot be kept outside of the Critical Root Zone (TPCRZ). TPCRZ for the entire duration of the construction, actions shall be taken to Trees to be protected shall require tree disperse the load, minimizing soil protection fencing to be set at the compaction and mechanical root TPCRZ as described in the IUM damage. Standard Drawing IL-690-A-B - TREE PROTECTION–FENCING and IUM These actions to be implemented by Construction Specification 91 CHAIN hand method include: LINK FENCE. For projects without highly significant or historical trees and Applying a minimum of 12 inches that will last for less than six-month of woodchip mulch to the area, duration, a non-treated wood lath snow fence or wire-mesh fence shall be used Laying three-quarter inch and solidly anchored to the posts. This minimum thick plywood, beams, area shall be protected from damage commercial logging or road mats during construction operations. over a four-plus inch layer of woodchip mulch, For projects over a six-month duration or trees that are considered significant Any erosion control method used within or historical, a chain link fence with IUM the TPCRZ shall be placed by hand and Construction Specification 91 CHAIN encompass the area 4 inches out from LINK FENCE or better (as approved by the tree trunk to three feet outside the the local Forester per local ordinances dripline of the tree, meeting the fence singularly or in tandem with the project line set at the TPCRZ. This area shall Engineer) shall be used. IUM Standard be maintained to prevent clearing, Drawing IUM-690-A-B TREE grading and development activities from PROTECTION–FENCING. Fencing encroaching within the TPCRZ. shall be a minimum of 4 feet in height. For chain link fencing, metal posts shall Outside the TPCRZ, erosion and be placed 6 feet (maximum distance) on sediment control measures shall be center (OC) and the fencing solidly installed to prevent sediment from anchored to the posts. reaching the TPCRZ. These measures include but are not limited to vegetative SIGNAGE Notices shall be posted on filter strips, woodchip mulch and rolled the fences prohibiting dumping and excelsior blankets. Measures such as disposal of waste near protected trees. woodchip mulch or excelsior blankets Signs shall be posted that identify the shall be a minimum of 3 inches deep up fenced areas as TPCRZ. to 5 inches deep, extend out from the fence 10 feet and shall be continuous SOIL EROSION CONCERNS In around the perimeter of the fence. Other HIGHLY URBANIZED AREAS, low use methods may be used if approved by areas inside the TPCRZ should be the Professional Forester, Certified mulched with three to five inches of Arborist or equivalent. premium woodchip mulch. 990B - 3 Installation shall cause no disturbance TREE TRUNK PROTECTION and IUM to soils. This area shall be maintained to Standard Drawings IUM-690-D TREE prevent clearing, grading and ROOT PROTECTION FOR AUGERING development activities from encroaching PRACTICES (Highly Urbanized Areas). within the protected TPCRZ. In areas where green and gray TRUNK PROTECTION IS REQUIRED infrastructure are intertwined, there must IN HIGHLY URBANIZED AREAS For be consultation with a local Professional sidewalk or other space limited areas, Forester or Certified Arborist concerning additional Tree Trunk Protection shall be species tolerance to the construction used. Tree Trunk Protection shall be practices. Refer to Table 2 - Tree implemented using IUM Standard Species Tolerance to Root Severance Drawing IUM-690-C – TREE TRUNK and Soil Compaction has been added PROTECTION. This standard requires a as a reference. minimum of 2 inch x 8 inch x 8 foot boards banded continuously around ROOT/SOIL MANAGEMENT No each trunk to prevent scarring of the construction activities, including the trees shown on the plan or designated placement of topsoil manually, shall be by the Professional Forester or Certified permitted within the TPCRZ. Adding of Arborist. Operations of the equipment woodchip mulch shall be done manually shall not break the plane of the fencing as specified in the contract, construction regardless of Tree Trunk Protection plan or equivalent document. All being installed. roadways, parking areas, and storage areas, parking, maneuvering of ROOT PROTECTION STRATEGIES In machinery, stockpiling of materials, or HIGHLY URBANIZED AREAS, the trees any other construction activities will not along sidewalks or other concrete be allowed upon unpaved areas located barriers that are currently within the within 10 feet of the TPCRZ of trees and dripline of the tree shall be enclosed plants designated to be protected. with chain link fence IUM Construction Specification 91 CHAIN LINK FENCE In HIGHLY URBANIZED areas where and the IUM Practice Standard Code the infrastructure is close to the trunk of 991 TREE PROTECTION – AUGERING the tree and the roots are one half inch shall be used in these cases. Other or greater in diameter, trenches should root/soil management techniques listed be excavated by hand, air spade or low below can also be incorporated into the pressure hydro excavation.