Record-breaking 'Populus deltoides' Hastings tree gets a trim from top arborist to preserve it

World champion tree climber and veteran arborist Scott Forrest was chosen specially for the job due to his experience. Photo / Supplied

The world's largest Populus deltoides has undergone life-saving surgery in Hastings this week.

Carefully, piece by piece, New Zealand's oldest and largest deciduous tree has had a trim – all in the aid of extending its life for as long as possible, while ensuring it does not endanger park users.

World champion tree climber and veteran arborist Scott Forrest has been heading the haircut and has been joined by young up-and-coming arborist Devon Judd.

"This is the calibre of arborist we need for this work given the age and importance of the poplar," Hastings District Council head arborist Steven Leggett said.

The Frimley Park tree has been surrounded by a security fence since November when movement in its base triggered further investigations.

The decision was made to remove about 10 per cent from the canopy of the tree, which would lighten the load on the base of the tree.

Contractor Hawke's Bay Tree Surgeons is using a scientifically prescribed method to take the weight from the top of the tree.

Hawke's Bay Tree Surgeons co-owner and lead arborist Jonty Apatu said the arborists were also checking for any disease in the canopy of the tree.

"Through this work we hope to retain this tree for many to enjoy for as long as possible," Apatu said.

"This is believed to be the largest deciduous tree in New Zealand and the tallest of its species [Populus deltoides - also known as American cottonwood, necklace poplar or black poplar] in the world. The interest in the process, given the age, size and fame of the tree, is very high," Leggett said.

The tree was planted in the 1870s, making it around 150 years old.

Until this work, it was the tallest tree in a park or reserve in Hastings, however that title would now pass to Havelock North's gum in the Village Green.

The Frimley Park poplar would still hold the largest girth record of any tree in Hastings' public parks and reserves, measuring 10.17 metres.

The tree is listed as a 'notable tree' on the New Zealand Tree Register.

The next tallest recorded specimen is in Montana, with a height of 33, so even with the estimated 8m-9m trim it may still hold its title.

Mr Leggett said plans for its replacement were in hand, given no tree could live forever. About 10 years ago a former council arborist had planted three poplars from the parent plant, ensuring the DNA continued.

All three were close to the parent plant and a decision on which would be specifically nurtured as a replacement would be made in the future.