Garden city overrun by weeds

Anyone visiting Canterbury’s garden city will notice that the garden is fighting for attention over the growth of unsightly weeds. The Christchurch City Council, no longer able to keep on top of weeds that are taking hold of cracks and unsealed surfaces, is breaking its budget to stop them taking over the city.

Why do the city streets, once pristine and distinguished, look like they’re uncared for, despite an increase of millions of dollars for weed control?

Rewind to 2015, when the Council deliberated on changes to weed killer use, Agcarm submitted in support of continuing to use the versatile weedkiller to manage weeds without any extra cost. This is because it requires less frequent applications as it kills the roots of the vegetation as well as the foliage.

Fast forward three years and recent media reports show that the use of alternate products in Christchurch can’t control weeds. The additional weed control budget of $11.5 million – approved, at the time, by city council rate payers has already been spent. An additional $850,000 is now needed to support these more expensive control options.

Hot water/steam or plant-based herbicides are more costly and less effective. The former does not kill the roots of the weeds and results in more applications to prevent re-growth. It can’t address stubborn and persistent weeds either.

Council park staff is calling for councillors to soften their position on glyphosate. A recent article on Stuff quotes a City Councillor as saying that the situation is “absolutely ludicrous”. “Our city is going backwards in its Garden City image as a consequence” (of the glyphosate ban).

At the time of the decision, the information presented by council staff was both misleading and misrepresented the facts.

The fact is that glyphosate has recorded over 40 years of safe use. Comprehensive toxicological studies repeated over this time have demonstrated the strong safety profile of this widely-used herbicide. Over 160 countries approve the safe use of glyphosate -supported by one of the most extensive human health, crop residue and environmental databases ever compiled on a pesticide.

IARC is one of four World Health Organisation programs to have reviewed glyphosate – the other three concluded that glyphosate is not a carcinogen or does not represent a hazard to human health.

Many of the concerns about glyphosate have resulted from the classification of glyphosate as a probable carcinogen (Category 2A) by the International Agency for Research on Cancer (IARC) in 2014. This classification puts it in the same category as substances like coffee, bacon and aloe vera. IARC classified processed meat like salami as carcinogenic to humans (Group 1).

The IARC report is not a risk assessment. It refers specifically to the chemical active and does not suggest that the use of glyphosate products, according to their registered use, pose any threat.

Chemical products such as glyphosate are among the most highly regulated in the world and are periodically reviewed. Neither of New Zealand’s regulators responsible for glyphosate – the Environmental Protection Authority and the Ministry for Primary Industries – nor Australia’s, considers glyphosate to be harmful.

In fact, no regulatory agency in the world considers glyphosate to be a carcinogen. The overwhelming conclusion of experts worldwide is that glyphosate, when used according to label directions, does not present an unreasonable risk of adverse effects to humans, wildlife or the environment.

Christchurch City Council must focus on rebuilding the city and providing effective infrastructure for future growth. Communities rely on public facilities like parks, nature reserves and recreational areas. The maintenance of these often requires the careful and responsible use of approved chemicals to manage weeds.

The Council needs to revisit its original decision. Using glyphosate-based products, according to label instructions, will help revive the glory of the garden city at no additional cost to the public.