Since mid-2016, Christchurch City Council has been reducing its use of chemical weedkillers by exploring organic alternatives and saturated steam.
They have bought a truck fitted with a 2000 litre water tank and a boiler unit and are using it the eastern suburbs to blast weeds growing by the roadside with jetted super-heated water.
“The boiler unit heats the water under pressure to a temperature of 120 degrees. The super-heated water is then jet blasted onto the weeds. It essentially cooks the weeds and kills them,’’ says Council Transport Operations Manager Steffan Thomas.
“We’re still in the early stages of analysing the benefits of this new methodology but so far it does seem to be pretty effective.’’
Citycare has recently rolled out a second truck that can thermally kill weeds.
Wairarapa councils have been considering the issue for even longer, since 2015.
Read the article at the Wairarapa Times-Age.
Brendan Tait is the owner/operator of Wellington-based Envirosteam, a contracting business which uses Weedtechnics’ machines to kill weeds, was approached for comment by the Times-Age;
He said New Zealand should lead the pack in finding alternatives to poison. “We’re all about the clean and green – but we’ve also got this old boy mentality of ‘spray it, she’ll be right’.”
Tait said steam killing of weeds was possible at a council level, but it took more commitment.
Four to six weeks after steaming, remaining seeds and taproots would sprout again, “but once you give it a second dose – then a third, its gone, its dead, there’s nothing coming back”.
However, the process was slower than using chemical spray applicators. “It can take twice as long – because I’m targeting, not blanket spraying.”
In terms of protective gear, Tait had no worries of carcinogens when steaming. He said steam could be applied in shorts and a T-shirt if you wanted to, with leather gloves to guard yourself when handling the hot applicator.
Tait was interested to see where New Zealand’s chemical conversation would lead after the Monsanto case. “It depends on what you read and by who. Sixty years ago, cigarette smoking wasn’t [considered] bad for your health.”
We’re interested to see where New Zealand’s chemical conversation is going as well, we know what we have to say about it! How about you?