When tears stream down the face of Levin man Phil Arnold, people often ask if him if he's okay.
It's not that he's upset. It's just that he's had allergies, asthma and hay fever ever since he came into contact with a privet tree seven years ago.
The 70-year-old had recently retired, but was a lawn mowing contractor for 27 years. Fully fit, he never had any hint of a health complaints until he cut down a row of privet trees when they were in flower.
Since that day he has suffered from allergies and severe hay fever and can pinpoint the onset of those allergies to the day he spent cutting down privet trees.
"I was perfect up until that day," he said.
"They're not little tears either...streams coming from eyes. People say 'what are you crying for?'"
Arnold said he just wanted to bring to light the health dangers with privet. He said they were everywhere and knew of other people affected in the same way.
He approached Horowhenua District Council with his concerns, and they cut down any privet on council land, but on private land any tree was the responsibility of individual land owners, he was told.
Arnold kept himself fit. On his walks around town he saw privet everywhere, which were just finishing their flowering cycle.
"I don't know what can be done about it...but if we bring it to people's attention," he said.
Privet trees, or Ligustrum lucidum, are widespread. They are covered in creamy yellow flowers and emit a sickly sweet smell. Thousands of Kiwis are thought to be allergic to the species.
A privet tree could grow to 10m tall, with dark green leaves that grew wild in gardens, on roadsides, and on reserves and wasteland.
On flowering it produced thousands of black fruits spread by birds. It grows rapidly and displaces native and other desirable plants and trees.
Listed as a pest plant, Forest & Bird New Zealand strongly encourages residents to remove any privet on their land, and stumps should be treated with root poison to halt regrowth.
One method of extermination was to drill several 12mm holes in the trunk every 20cm around the trunk, and pour in 2g of metulfuron in a strong solution with an added penetrant, killing the tree, which would then disintegrate over time.
Once popular for hedging, they were now banned from sale and considered to one of the most invasive species in New Zealand, most common north of the Bay of Plenty, and also found in the warmer parts of the South Island.
Horowhenua District Council's Parks and Property Lead South Ann Clark said:
"Horizons Regional Council identifies pest plants in its Regional Pest Management Plan. As privet is not currently included in the Plan, Horowhenua District Council has no specific management plan to control it.
"We may consider it as a less desirable plant to be removed when we do routine refurbishments of our parks and reserves. However, there are currently few privet trees in our parks and reserves."