(A) The contractor shall protect and preserve all trees and natural areas along the line of work, and will be held responsible for any damage to trees. Construction fencing shall be placed to fence off designated areas at the drip edge of the trees to be protected. Where necessary to preserve a tree and its main roots, the contractor shall tunnel under such tree. Where specifically called for on the drawings, the contractor shall remove trees completely, including stumps and main roots.
(B) Where tunneling is required, augering shall be done in a manner to protect the trees and at a distance away from the tree in accordance with the following table:
Tunneling or Augering Beneath Tree Roots
| |
Tree Diameter (DBH) | Minimum Auger Distance |
Tunneling or Augering Beneath Tree Roots
| |
Tree Diameter (DBH) | Minimum Auger Distance |
Up to 2" | Auger 1 foot from trunk of tree |
3 - 4" | Auger 2 foot from trunk of tree |
5 - 9" | Auger 5 foot from trunk of tree |
10 - 14" | Auger 10 foot from trunk of tree |
15 - 19" | Auger 12 foot from trunk of tree |
19" and Over | Auger 15 foot from trunk of tree |
Note: Diameter Breast Height (DBH) is measured 4.5' above the ground | |
(C) The minimum depth of auger within the root zone, as described above, shall be 24 inches below the soil surface. In any event, the tunneling must be below the major root system of the tree. All voids around the tunneled or augured facility shall be backfilled with excavated material and thoroughly compacted to avoid settlement. Compaction must be completed without compacting the soil within the root zone.
(D) Where tunneling is not required for trees close to the trench and root trimming is necessary, the contractor shall hand trench ahead of the machine digging and cut all roots cleanly to minimize damage to the roots.
(E) Tree branches shall be tied back to protect them from the contractor's machinery where necessary.
(Ord. 31.26, passed 5-13-13)