Whanganui's "tree lady" has 16,500 living beings to worry about.

Claire Lilley's job title is parks officer (arboriculture). She started work for Whanganui District Council in February last year.

She's responsible for 6,500 street trees and 10,000 others in parks, reserves and along walkways. Her guiding document is the council's 2016 Street Tree Strategy.

Mrs Lilley likes a tree for all seasons - spring blossom, attractive leaves and autumn colour. Cherries and liquidambars are two of her favourites.


Despite being a peaceful influence, trees can cause massive disputes, sometimes between neighbours over the same tree.

"Often you have to do what's best for the tree. People are generally transient and the trees are going to be there longer than they are," Mrs Lilley said.

Most of her work is with street trees, and she said not many provincial towns had as many as Whanganui.

But Whanganui's street trees are ageing. They have maintenance and infrastructure issues, so there's lots of work to do.

In Aramoho's Lewis Ave, for example, she made the decision to take out every second oak tree on the north side of the street. The trees needed lengthy and expensive pruning every year to keep them out of power lines, and the pruning has formed strange shapes.

"It was wasting a lot of money doing this work," she said.

Whanganui suburbs have their individual tree flavours. Whanganui East is colonial, Aramoho is more cherries and birches, and Castlecliff-Gonville has natives to withstand the salty coastal winds.

People often say they would prefer native trees on their verges - but not so many are suitable. The totara outside Mrs Lilley's house is likely to get much too big, she said.

Choosing street trees that will fit the suburb's character and the space available and not cause any problems is a fun part of the job. Even better is watching those trees grow and become part of the landscape.

She had that pleasure in her previous job - 13 years as tree officer for Welwyn Garden City. It's north of London and was designed in the early 1900s with formal plantings and avenues of trees demarcating vistas.

In England her work was only half outdoors. The other half was behind a desk. England has a lot of legislation protecting trees, and she had to be involved in some complex planning decisions.

Welwyn Garden City was a nice, green and leafy place to live, she said, but New Zealand's open spaces had more appeal for her young family. They decided to emigrate, after visiting relatives here during a holiday three years ago.

Getting residence was easy, she said. Arborists were needed in New Zealand at that time and she has a national diploma in arboriculture.