Boiled weeds recipe trialled

Ruapehu Bulletin, Volume 12, Issue 541, 21 June 1994, Page 3

Boiled weeds recipe trialled

Ruapehu could have chemical-free weed control on council land, but at a price. In Ohakune last week was a Waipuna weed control system demonstration unit, which uses hot water under pressure to control weeds along kerb and channel, footpaths, fences and around trees. The unit heats water to about 105°C and pumps it through ground-level nozzles, with rollers attached to ensure the right distance is kept. The hot water kills all soft-tissue plants andcan kill seeds on the surface but not buried seeds. The system is more expensive than using herbicides because it is slower, covering 1-1. 5km per hour in contrast to spraying at 4km/hour. It is estimated that it costs about 20 to 30 per cent more than using Round-up spray. Other sprays which are even cheaper are being banned from use by most councils in the country. The treatment would have to be carried out two to three times a year. Advantages are that the method can be used in almost any weather; an operator can see where they have. treated; there is no herbicide falling into gutters to be washed into waterways; it leaves no residual effect.