A decision on continuing to use the weed-killer Roundup on city parks is deferred to allow the Tauranga City Council's agrichemical forum to speak in support of its report.

TAAF, the Toxic Agrichemical Advisory Forum, is recommending the council change its approach to the use of glyphosate sprays, one of which is Roundup, because they may be even more poisonous than advertised.

Patents of RoundUp and its main active ingredient glyphosate expired in 2000.

There are now 35 glyphosate poisons identified in the New Zealand Novachem Agrichemical manual and each has its own mix of adjuvants – additive chemicals that TAAF says are in at least one instance even more toxic than glyphosate itself.

The TAAF forum wants council staff to research the additives to find out which glyphosate products are safest to use.

Staff are unable to do so and have kicked the question upstairs to the politicians.

TAAF forum representatives were to speak in support of their report, but didn't turn up to the committee meeting because they are upset at the way their report was bundled with the staff report to the committee, says Jeremy Boase, acting group manager on city directions.

In the normal manner of report presentations to council, the staff summary and background issues are included, as well as the complete TTAF report and recommendations.

Councillors decided to defer discussion on the issue until they can get someone from TAAF to speak to it.

Meanwhile the status quo will continue with chemicals in use IRMA approved.

The TAAF is an informal advisory group formed in 2009 and comprises interested and knowledgeable people who can assist the committee in its determination of acceptable poisons and circumstances for their safe use.