Poplars' removal recommended

The appearance of Lake Esplanade could soon be very different, as an arborist's report recommends four ''high-risk'' Lombardy poplar trees growing in St Omer Park be removed and the remaining 17 removed in stages.

The recommendation comes in a report to the Queenstown Lakes District Council, commissioned after one of the tree species falling at 6.50pm on January 17 during high wind and consequently damaging seven cars, damaging a motel roof and blocking an arterial road for several hours.

No-one was injured when the 30m tall Lombardy poplar snapped at its base and fell across Lake Esplanade from St Omer Park.

The report by arborist Samuel Earp, of GreensceneNZ, concluded ''the trees are over-mature'' and more robust and longer-lasting trees should be planted in their place.

''Problems associated with old age are beginning to manifest themselves, in the form of cavities and heartwood decay. The extent of this manifestation was revealed by the tree failure event that occurred on 17th January 2014.''

It is recommended a management plan ''be developed which details the staged removal of the remaining Lombardy poplars within St Omer Park and the requirement to undertake suitable replacement planting, both undertaken over an extended time frame''.

Also recommended is reducing the remaining Lombardy poplars' existing height and bulk by a third, before their complete removal.

The Lombardy poplars in the park are thought to be about 120 years old and, given the species' short lifespan, ''the Lombardy poplars of St Omer Park are considered to be coming to the end of their useful life expectancy and are starting to succumb to problems associated with over-mature trees''.

Mr Earp determined the tree which fell had hollow parts in the base of its trunk with large areas of rotten wood (indicative of heartwood decay). A closer inspection revealed soft, spongy wood, indicating white rot.

Some of the trees showed signs of previous limb failure and such failures would happen with increased frequency as the trees aged, he said.

The report also assessed four black poplars in the park as being in ''generally good health with fair form'' and one mature grey poplar, which is also of no major concern.

The council's senior communications adviser Michele Poole said the recommendation to remove the four high-risk Lombardy poplars ''is being actioned'' and the council expected to have a removal date next week.

She was not able to comment about the recommendation to remove the remaining 17 Lombardy poplars.

A report on the single tree which fell has been referred to the council's insurance company.