Critics weed out Banks' error

John Banks' billboard featuring what botanists have confirmed as pampas grass, not native toitoi as Banks had assumed. Photo / Doug Sherring

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Billboards all over Auckland have appeared featuring a noxious weed - pampas grass - and a certain super mayoral candidate.

But John Banks has laughed off suggestions that he shares similar traits to the weed which can grow to 6m tall and smothers native vegetation.

Botanists confirmed that the plant which appears in the foreground of Banks' campaign advertisements was pampas, and not native toitoi as Banks had assumed.

The Auckland city mayor said: "Some people would describe me as a noxious weed. I've never heard of pampas grass."

Banks said his campaign team would not change the billboards in light of the new information.

"We're glad that it's creating some interest. It's good to know that people are noticing these things. "

The Auckland Museum's curator of botany, Ewen Cameron, said he was "very confident" it was pampas grass.

He said: "The upright appearance tells us it's pampas grass. They're sticking straight up. The toitoi heads hang to one side. They're a little bit limp. Whereas the pampas grass is very much erect.

"You can also see the pink colouration in them. The pampas are usually pink whereas the toitoi are never pink."

Green Party conservation spokesperson Kevin Hague said it was an "unfortunate and thoughtless" mistake. He said Banks had "not exactly covered himself with glory on environmental issues".

"It's the kind of detail that's important to get right. It's not the symbol I'd choose for my mayoral bid," said Hague.

Massey University political marketing expert Claire Robinson said the billboard was unlikely to affect Banks' chances in the race.

"If you're predisposed from vaguely to definitely voting John Banks, nothing like this is likely to change your mind," she said.

She said that for Aucklanders who didn't like Banks, this was just another reason not to vote for him.

"They probably should have been more careful about the grass but for them it was getting the right photo," said Robinson.

Pampas grass is described on a Conservation Department website as "very invasive, forming dense and often impenetrable stands". The plant, from South America, is listed on the National Pest Plant Accord, meaning it is illegal to be sold in New Zealand.

Cameron said the Auckland Regional Council and the Department of Conservation spent thousands of dollars each year trying to control pampas grass. "You're talking big money controlling pampas grass."