Christchurch gets steaming mad at weeds

Thermal weeding using super-heated water is the latest weapon being used in the fight to keep weeds down in Christchurch.

Christchurch City Council has been working to reduce its use of chemical weed killers, particularly those containing glyphosate, since mid-2016.

A Citycare worker blasts roadside weeds with super-heated water. Photo: City Care

Its contractors have been using organic sprays to keep the weeds down in parks and now Citycare is trialling the use of super-heated water to kill roadside weeds.

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.