Root harm prevention
 31. (1) If a Category 2 or 3 butternut tree is to be retained in an area where other butternut trees will be impacted by impactful actions, or in an area where a larger activity as described in clause 22 (b) is to be carried out, the following measures shall be taken to protect the root harm prevention zone of each Category 2 or 3 butternut tree that is to be retained: 1.  Before undertaking any impactful actions, i.  the butternut tree to be retained and its root harm prevention zone shall be marked with non-invasive marking, ii.  if there is a risk that any impactful actions could encroach on the root harm prevention zone of the butternut tree to be retained, protective fencing shall be installed and maintained around the perimeter of the root harm prevention zone to prevent the encroachment, and iii.  if there is a risk that any impactful actions could cause erosion in the root harm prevention zone of a butternut tree to be retained, silt fences shall be installed around the perimeter of the root harm prevention zone to prevent the erosion. 2.  The following actions shall not take place within the perimeter of the butternut tree’s root harm prevention zone: i.  Transport or operation of heavy equipment. ii.  Placement of temporary facilities or temporary roads for the purpose of construction. iii.  Excavation of soil or other substrates. iv.  Storage of materials such as excavated soil, debris or construction materials. v.  Production of ruts or compacted soil. vi.  Removal of vegetation in a manner that destabilizes soil. 3.  In order to prevent disturbance, compaction and erosion of soil in the root harm prevention zone and harm to the roots of the butternut tree, the actions described in paragraph 2 shall not take place within a five-metre buffer area that surrounds the perimeter of the butternut tree’s root harm prevention zone. 4.  If, despite paragraph 3, the actions described in paragraph 2 occur within the five-metre buffer area described in paragraph 3, measures shall be taken as soon as practically possible to remedy the effect of those actions on soil conditions within the buffer area. 5.  Tree and root harm prevention zone markings, fencing of root harm prevention zones and work areas shall be inspected prior to commencement of any impactful actions in order to ensure the mitigation measures intended to protect retained butternut trees are in place and effective and shall be inspected, maintained and repaired as necessary until the impactful actions cease. (2) The root harm prevention zone of a butternut tree referred to in subsection (1) shall be the area surrounding the stem of the tree determined by, (a)  measuring the diameter of the tree stem in accordance with the Butternut Assessment Guidelines; (b)  determining the diameter range set out in Column 2 of the Table to this subsection within which the tree stem’s diameter falls; and (c)  tracing around the stem of the tree a circle with a radius that is equal to the number of metres indicated in Column 3 of the Table opposite the diameter range determined under clause (b). table   root harm prevention zone Column 1   Item   Column 2   Tree stem diameter    Column 3   Root harm prevention zone (measured in metres from stem) 

  1.   Less than 3 centimetres    6 

  2.   At least 3 centimetres but less than 15 centimetres   9 

  3.   At least 15 centimetres but less than 30 centimetres   12 

  4.   At least 30 centimetres but less than 50 centimetres   18 

  5.   At least 50 centimetres   25  (3) For the purposes of determining the root harm prevention zone of a butternut tree under subsection (2), a butternut tree that measures less than 1.37 metres in height shall be deemed to have a tree stem diameter of less than three centimetres.