ITEM
658 TREE ROOT AERATION
658.01
Description
658.02
Materials
658.03
Preparation
658.04 Aeration
for Trees Not Welled
658.05 Aeration
with Tree Wells
658.06 Earth
Embankment
658.07 Method
of Measurement
658.08 Basis of
Payment
658.01 Description. This work consists of
furnishing and placing the necessary aggregate and tile for the protection and
aeration of the roots of trees and shrubs.
Use
removed or excavated materials in the Work when the material conforms to the
specifications; if not, then recycle or dispose of the material according to 105.16 and 105.17.
658.02 Materials. Furnish aggregate for tree root
aeration and protection consisting of No. 4 or 467 limestone or gravel with a
maximum sodium soundness loss of 15 percent.
Furnish
4-inch (100 mm) pipe conforming to 611 Type E conduit. Furnish embankment conforming to
Item 203.
658.03 Preparation. The feeding root area to
be protected and aerated is the ground surface area lying within the periphery
of the tree or shrub not marked for removal. Prepare these areas by
excavating all vegetation, wood, brush, and debris.
658.04 Aeration for Trees Not Welled. Where the
earth fill is less than 12 inches (300 mm) and more than 4 inches (100 mm) over
the feeding root area, loosely spread an aggregate aeration course of one-half
the height of fill, but not less than 3 inches (75 mm), over this area.
At the tree trunk, increase the thickness to the height of the fill and extend
it outward from the tree trunk in collar form for a distance of 15 inches (0.4
m). Place a 2-inch (50 mm) layer of straw or hay over the aggregate.
658.05 Aeration with Tree Wells. Place an
aeration course of aggregate while constructing the tree wells and before any
other filling. Do not place any aggregate inside the tree well (between
the wall and the tree trunk). Place the aggregate over the entire feeding
root area outside of the tree wells to a total depth of 6 inches (150 mm)
for each 12 inches (300 mm) of earth fill, or proportion thereof, but place a
minimum depth of 6 inches (150 mm) regardless of depth of overlying fill.
Place a 2-inch (50 mm) layer of straw or hay over the aeration layer.
658.06 Earth Embankment. Perform
excavation and embankment, as necessary, according to Item 203.
658.07 Method of Measurement. The
Department will measure Tree Root Aeration by the number of cubic yards (cubic
meters), measured in the carrier or truck according to 109,
of the aggregate furnished, placed, completed, and accepted.
658.08 Basis of Payment. The
Department will pay for embankment and excavation under Item 203 and the pipe under Item 611.
The
Department will pay for accepted quantities at the contract price as follows:
Item
Unit
Description
658
Cubic
Yard
Tree Root Aeration
(Cubic Meter)