"Investigation clearly showed severe compaction of the soil around the trees, due to the popular use of the area as a carpark, so the council worked with several contractors to put in place a remediation plan that would give the trees their best chance of recovery, while retaining the car parking spaces beneath them," Gill said.
The work was undertaken in several stages over four days. First, the carparking area under the trees was cleared of its gravel and radial trenches made within the root zone of each tree.
Roy Hollister of Complete Tree Care Ltd used an air-spade to excavate stones and soil from around the roots without damaging them, expertise he gained while working as an arborist in the United States.
The trenches were lined with humates specifically formulated for the site by Tuturu Products Ltd, then refilled with the air-spaded soil.
The whole area was next covered with an interlocking 'honeycomb' grid, made of recycled plastic, designed to protect the tree root zones from compaction, while allowing good circulation of nutrients, water and air.
Layers of mulch and gravel were then applied to provide a totally new carparking surface, and mulched gardens planted around the tree bases, planted with native grasses from Bushlands Trust.
"The crew also performed an unofficial archeological dig that uncovered a two shilling coin, a thruppenny bit, two pennies, a faded GayTime icecream spoon and a mystery looped wire," Gill added.
"Once the work area was reopened to the public, several locals praised the new carpark look and said they looked forward to seeing the pohutukawa reviving in the near future."