Toetoe and pampas are popular to include in floral arrangements - but one of them is forbidden under the Biosecurity Act. Photo / Supplied
Couples using a popular noxious weed in their wedding bouquets and decorations are unknowingly flouting the law, the Ministry for Primary Industries (MPI) says.
A growing wedding trend to use pampas grass in decor is taking over social media, but biosecurity experts have warned the practice could be helping the invasive South American plant to also take over the country.
Pampas grass imitates the native New Zealand toetoe - often misspelt as toitoi - but is harmful to local environments and particularly difficult to get rid of.
"Because pampas tolerates heat and frost, salt, wind, wet and drought, moderate-shade, most soils, low fertility, and recovers quickly after fire, there's pretty much nowhere in NZ that it can't do well," said Greater Wellington Regional Council biosecurity advisor Katrina Merrifield.
The weed quickly colonises sprayed, burnt, slipped, or otherwise disturbed sites, and replaces groundcovers, shrubs and ferns.
Not only does the plant create fire hazards, but it also provides homes for pests such as rats and possums, and grows densely.
Merrifield said people using pampas decoratively in their weddings should be aware of "how fast it can invade almost any habitat and become an issue", and encouraged them to use toetoe instead if possible.
But a spokesman for MPI now says not only should people be discouraged from using the weed, but that it is actually forbidden under the Biosecurity Act 1993.
"There are two species of pampas grass in New Zealand and both are unwanted organisms under the Biosecurity Act," the spokesman said in a statement.
"This means that people are not permitted to spread, trade or propagate it in New Zealand without permission. This includes using it for floral arrangements or other use."
The Act specifies that "communicating" is not permitted - meaning moving the plant from place to place or from person to person is forbidden.
"It is also not permitted for the pest or unwanted organism to be in a place where organisms are sold or exhibited. Florist shops would fall under this."
The two species are included under the National Pest Plant Accord, which bans a number of plant species from sale or trade.
The Biosecurity Act does not, by default, prevent landowners from growing the plant on their own land, but many regional councils include pampas grass as pests in their Regional Pest Management Plans.
The specific rules for this vary between different regions.
"The penalty for knowingly spreading, trading or propagating a pest or unwanted organism is a fine up to $100,000 and/or imprisonment up to five years for an individual, or, in the case of a corporation, a fine up to $200,000," he said.
Future bride Loren this week took to social media to warn others the plant they were using in their weddings could harm the environment.
Loren, who is currently studying biodiversity management, said pampas was "just hell".
"People probably also don't know that they're a noxious weed, which is a real shame."
What's the difference between toetoe and pampas?
Toetoe produces drooping, light golden-yellow flowerheads from September to January, whereas Pampas points upright and produces straight, dense, fluffy white-pinkish flowerheads from January to June, which fade to a dirty white as the seed forms. Another type of pampas produces bright purple flowerheads.
Pampas leaves will also snap easily and dead leaves will curl at the base, while toetoe leaves don't.