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1.1 Proper Work Environment

Awareness of Existing Conditions: It is your (or your contractor's) responsibility to be aware of all surface and sub-surface conditions that would negatively impact the health of plantings or underground utilities. Do not proceed with work until unsatisfactory conditions have been corrected. Do not mix, place, or grade soils when they are frozen or too wet.

Before Planting: All planting soil preparation (see 2 Materials and 3 Earthwork) and irrigation work should be completed prior to the installation of any plants. Planting operations should not begin until the irrigation system is completely operational for the area(s) to be planted.

Planting Season: Planting should be performed during periods when weather and soil conditions are suitable in accordance with locally accepted horticultural practices. Your local nursery likely has staff to guide you with details for a specific condition. Generally speaking, do not install plants into saturated or frozen soils, and do not install plants during inclement weather, such as rain or snow or during extremely hot, cold or windy conditions.

1.2 Project Management

Coordination: Prior to the start of work, prepare a detailed schedule of the work for coordination with other trades. You (or your contractor) shall coordinate with all other work that may impact the completion of the work. Coordinate the relocation of any Irrigation lines, heads, or the conduits of other utility lines that are in conflict with tree locations. root balls shall not be altered to fit around lines.

General Observations: Confirm that no conditions are present which are detrimental to plant growth. Make sure that any utility and irrigation work has been completed as planned. Most importantly, if unsatisfactory conditions are encountered, determine the corrective action before proceeding.

Drainage Observations: Confirm that no adverse drainage conditions are present. Make sure that the Subgrade is at the proper elevation and compacted as required. Subgrade elevations must slope toward the under drain lines as shown on the Final Plan (if shown).

Soil Observations: Confirm that the surface of all areas to be filled with planting soil are free of construction debris, refuse, compressible or biodegradable materials, stones greater than 2 inches diameter, soil crusting films of silt or clay that reduces or stops drainage from the Planting Soil into the subsoil; and/or standing water. Remove all unsuitable material from the project site.

1.3 Storage and Handling of Materials

Soil Storage and Handling: Protect soil and soil stockpiles from wind, rain, and washing that can erode soil or separate fines and coarse material. Contamination by chemicals, dust, and debris may also be detrimental to plants or soil drainage. Cover the stockpiles with plastic sheeting or fabric at the end of each workday. For longer term protection, compact or track the soil surface and cover with a breathable fabric, or plant with annual grasses as appropriate for the season, location, and length of expected time of storage.

Plant Storage and Handling: Protect materials from deterioration during delivery and storage. Provide a protective covering over all plants during transporting. Adequately protect plants from drying out, exposure of roots to the sun, wind, or extremes of heat and cold temperatures. If planting is delayed more than 24 hours after plants arrive to the project site, set the plants in a location protected from the sun and wind. Provide adequate water to the root ball package during the shipping and storage period. Provide a staging area for plants and other supplies, but do not deliver more plants to the project site than there is space available for adequate storage conditions. 

Bulk Storage and Manufactured Products: Bulk materials such as soil, mulch, or aggregate should never be stored within the Tree and Plant Protection Areas (see 4.2). Store all manufactured packaged products and material in a dry enclosed space suitable for the material and meeting all environmental regulations. Biological additives should be protected from extreme cold and heat. All products should be freshly manufactured and dated for the year in which the products are to be used. Store all chemicals in a weather protected enclosure.


1.4 Digging Around Utilities

Determine the Location: You (or your contractor) should carefully examine any civil, record, and survey drawings to become familiar with the existing underground conditions before digging. Once the locations of underground utilities are known and you are ready to dig, always perform work in a manner that will avoid damage. Whenever possible, hand excavation is the best method for avoiding damage.

Notify Your Local Utility Locator: Notify your local utility locator service (ph#___________) which is likely required by law for all planting areas and other areas that you are digging. You are responsible for knowing the location and avoiding utilities that are not covered by the local utility locator service.

1.5 Flagging Existing Trees and Shrubs

Flagging Plants to Remove: Flag all trees and shrubs to be removed by wrapping orange plastic ribbon around the trunk prior to the start of tree and shrub removal. For clarity, you may want to mark all trees and shrubs with orange paint in a band completely around the base of the tree or shrub approximately 4.5-feet above the ground (chest height).

Flagging Plants to Remain: Flag all trees and shrubs to remain with a white plastic ribbon tied completely around the trunk or each tree and on a prominent branch for each shrub. 


1.6 Drain Pipe

Material: Drain pipe shall be 4-inch diameter perforated pipe of various strength. The strength of the pipe material used is dependent on the condition in which it is applied.

Light-Duty: Single wall corrugated exterior HDPE pipe. All fittings, elbows, unions, T’s and screw caps shall be the same material and from the same manufacturer as the pipe. All joints shall be gasketed bell and spigot.

Medium-Duty: Double wall (smooth interior wall with a corrugated exterior wall) PVC pipe with holes only on the bottom quadrant. Make sure that all fittings, elbows, unions, T’s and screw caps are the same material and from the same manufacturer as the pipe. “T” and elbow joints shall be sanitary type connections. All joints shall be gasketed bell and spigot.

Heavy-Duty: PVC Schedule 40 pipe with holes only on the bottom quadrant of the pipe. All fittings, elbows, unions, T’s and screw caps shall be the same material and from the same manufacturer as the pipe. “T” and elbow joints shall be sanitary type connections. All joints shall be solvent welded.

Instructions: Trench lines to the depths and widths shown on plans.  Then place 2–3 inches of coarse sand (see 2.4) as bedding for pipes.  Next, place the pipe  in the trench at the specified depth with the holes facing down. If a pipe with holes on all sides is used, drape a 12-inch wide piece of 4 mil plastic over the top of the pipe. Add a clean out pipe reaching the surface at the uphill end of each pipe run, and connect the pipes to a manhole or daylight outfall. Once the pipe is laid, cover the sides and top with coarse sand, with a minimum of 4 inches of coarse sand cover above top of pipe. Backfill the trench with planting soil (see 2.5) compacted to same level as stated in the planting soil requirements (see 2.5).

Drain Pipe Clean Out: Clean out risers shall be 4 inch diameter Schedule 40 PVC solid pipe compatible with the bottom fitting and the clean out screw cap. Use an elbow fitting at the bottom of the clean out riser. When the clean out is in the middle of a pipe run, the fitting shall be a sanitary T fitting. The screw cap fitting shall also be PVC Schedule 40.


1.7 Site Clean-Up

During Construction: Keep the site free of trash, pavements reasonably clean, and your work area in an orderly condition at the end of each day. Clean up any spilled or tracked soil, fuel, oil, trash, or debris from all surfaces within the project or on public right of ways and neighboring property. Remove trash and debris in containers from the site preferably no less than once a week, and remove all construction debris and material, including any construction materials, from the subgrade. 

After Construction: Once installation is complete, wash all soil from the pavements and other structures. Ensure that your mulch is confined to the planting beds, and that all tags and flagging tape are removed from the site. Seals are to remain on the trees and removed at the end of the warranty period (if a warranty is included). Lastly, remove and dispose of all excess planting soil, subsoil, mulch, plants, packaging, and other material brought to the site.

1 Site Preparation

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