201 Clearing and Grubbing - Ohio Department of Transportation

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201 Clearing and Grubbing
General
Specification Changes
Disposal of Materials
Policy
Plan Notes
Tress Located within the Plan Limits Allowed to Remain
Scalping (201.04)
Documentation Requirements – 201 Clearing and Grubbing
General
The purpose of this section is to establish uniform practices for clearing, grubbing, scalping, and removing trees and stumps
within the areas designated in the plans.
The following terms are defined for clarity:
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“Clearing” is cutting down all of the trees and brush.
“Grubbing” is clearing by digging up roots and stumps.
“Scalping” is removing the remaining roots, sod, grass, agriculture crop, sawdust, and other vegetation so that the soil
is completely exposed. This does not include removing topsoil.
Varying interpretations as to the extent of removal are possible where these removals are set up on a lump sum basis. It is
necessary to exercise judgment in the administration of this item to accomplish the desired results.
Specification Changes
There only specification change from the 2005 to 2008 specification book consisted of adding additional restrictions on the
movement of regulated material into and out of Ohio. These changes were the result of the Emerald Ash Borer infestation.
Disposal of Materials
All material disposals in the 200-series of C&MS refer to sections 105.16 and 105.17. The following statement is in 201.01 and
is repeated throughout the 200’s:
“Use all suitable excavation material in the work. Alternatively, legally use, burn, or dispose of all material according
to 105.16 and 105.17.”
The use, reuse, and/or disposal of these materials may be regulated. (See section “105.16 Borrow and Waste” of this manual).
Policy
It is Department policy to remove only those trees that must be removed for the construction and maintenance of the highway and
for the safety of the traveling public. In certain circumstances, it is desirable to leave healthy trees in place.
Plan Notes
There are three plan notes that may be used by the Department to determine the extent of the clearing and grubbing work on the
project. These notes are described below and in the Location & Design Manual, Volume 3, Appendix B. In every case, the plan
will denote the limits of the clearing and grubbing.
Plan Note G109A
When Plan Note G109A is used, no trees will be specifically called out for removal. Everything is removed within the areas
denoted in the plan. In this case, the Contractor has the maximum risk if his field count is not accurate. This note is often used
on small projects.
Plan Note G109B
When Plan Note G109B is used, trees and stumps are marked for removal on the plan. This note is used where the designer can
reasonably count all of the trees within the work limits. This count should be accurate at the time of the count.
The count is not necessarily correct at the time of construction. The Contractors are responsible to visit the site prior to the bid.
This allows the Contractor to take tree growth into account. Typical increase in growth is generally about 25 percent. This
depends on the time between the count and construction.
The Contractor should bring large discrepancies between the plan count and the actual conditions to the Department’s attention
prior to the bid.
Plan Note G109C
When Plan Note G109C is used, everything in the plan limits is removed except for the trees denoted as “Do Not Disturb”.
The plan denotes some trees and stumps, where feasible. In other locations, the plan denotes heavy wooded areas. An estimated
count is given in the heavy wooded section. This estimate is based on representative counts in the heavy wooded areas.
There are inherent inaccuracies in this count. The Contractor will be able to make an informed decision in his bid by the
knowledge of how the count is made. By denoting the type and accuracy of the tree counting, it minimizes the claims and change
orders from this item of work.
Markings for trees to remain in place should be temporary and not result in an undesirable appearance beyond the life of the
contract.
Trees Located within the Plan Limits Allowed to Remain
Trees that are located within the plan clearing and grubbing limits technically must be removed. There are circumstances,
however, where the Engineer may consider leaving trees in place or making other changes to the contract.
It may be desirable to leave some trees because they are aesthetically pleasing and can provide structural value to an embankment
or slope. Leaving flowering trees and shrubs such as dogwood, redbud, hawthorn, and other attractive growth should be given
serious consideration. Special consideration should be given to rest areas or other specific nature locations.
The Project Engineer will contact the District Environmental Coordinator for recommendations on the attractiveness of trees to
remain in place.
Where trees are allowed to remain in place, the area surrounding the trees should be cleared of undesirable undergrowth to
provide an attractive appearance and to simplify maintenance.
Trees located within the plan work limits but outside the clear zone may not require removal. It is required to remove trees
within the clear zone or a minimum distance of about 30 to 40 feet (9 to 12 meters) from the edge of the travel lanes. The actual
clear zone distance depends on the roadway type. The Project Engineer needs to contact the District Office of Production to give
approval recommendations on the clear zone.
It is not necessary to remove trees beyond areas required for construction if the grading section is in a cut with a 3:1 back slope,
or is in fill with a depth requiring a guardrail.
All trees considered for remaining in place must be in good condition. A tree should be removed if it is dead, fallen, or
unhealthy.
It may be necessary to remove some trees for fence or noise wall construction. This type of removal must be within the right-ofway limits and should not be greater than 10 feet (3 meters) in width in dense growth. Where trees are scattered, the removal
should be confined to trees that are in line with the fence or noise wall.
The appearance of a mechanical cutting swath should be avoided when trees are left. This can be accomplished by having a
curved or irregular tree line defining the area rather than a straight-line effect.
Scalping (201.04)
It is essential that the project enforce scalping work when it is required.
Scalping is not required under an embankment where the embankment height is greater than 9 feet (3 m) to the subgrade
elevation and when the existing slope is 8:1 or flatter. Both conditions must be true for the location not to be scalped. See Figure
201.04.1 for an illustration.
This requirement is in the specifications to ensure good friction between the existing foundation and the new embankment. This
construction technique minimizes future potential sliding.
<9 ft in height
>9 ft in height
Flatter than 8:1
Steeper than 8:1
Scalping required
Scalping required
>9 ft in height
Flatter than 8:1
Scalping not required
Figure 201.04.1 - Scalping Requirements
Documentation Requirements - 201 Clearing and Grubbing
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Proper Disposal (see 105.16 and 105.17).
Mark Right-of-Way or cutting limits.
Check the field conditions for accuracy.
Count Trees or Stumps, if these are set up for individual payment.
Check material removals according to 201.03.
Check the required scalping locations.
a. Use 201.04 for embankment foundations.
b. Use 203.05 for benching areas.
Measure and pay according to 201.05 and 201.06.
Document on form CA-D-3A or CA-D-3B.
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