Winning The War With Weeds
Weeds around Auckland City will be wilting at their roots after a decision to spend an additional $300,000 in the 2001/2002 financial year was made by Auckland City’s Parks and Recreation Committee recently. Subject to budget approval by the Combined Committees of Council, the Committee also endorsed an implementation programme designed to progressively achieve a 75% reduction in herbicide usage levels by 2005.
“Six years ago there were up to ninety different types of herbicide in use in parks, reserves and along the streets in Auckland,” said acting Chairman, Councillor Bill Christian. “Today, we have reduced that number to only three,” he said. He attributed the success of the policy so far to hard-working Council officers and to the establishment of the Weed Management Group. Formed two years ago the Group provides weed management advice and monitors policy implementation. It also considers applications for ‘non-approved’ herbicide use needed for extra difficult noxious weeds.
There are eleven members of the Group with representatives from the Department of Conservation, Auckland Regional Council, Landcare Research, AgResearch, contractors, and a community representative and staff members with expertise in the parks, street environments and parks planning areas.
Before the introduction of the policy, restrictions only applied to organophosphates. The policy has ensured that it now concentrates on reducing many other different herbicides as well. “We are currently using Roundup, Escort and Versatil which control most general weeds, woody weeds and turf weeds respectively”, said Councillor Christian. “They are considered to combine the best weed control results with the lowest toxicity ratings”.
Weeds in all playgrounds in Auckland City are now being controlled with non-herbicides. Parks officers will grant permission for minor spot spraying using the three previously mentioned herbicides, if it is deemed necessary. A turf weed management trial is currently underway at Michaels Avenue Sportspark. This area was chosen as it has three sports fields adjacent to each other allowing for a clear comparison and assessment of the results.
The first field is the control field where
current maintenance regimes will continue. Field two will
be subject to an intensified maintenance regime and the
third field will be intensively fertilised. The objective
of the last two trials is to establish optimum growing
conditions for turf grasses to allow them to out-compete
weed species. Councillor Christian said that it would
probably take a year to verify results and several years to
show consistency in the results after which the maintenance
regimes will be extended citywide.
Contractors are required to keep accurate logs of which herbicides are being used and for what purpose. It will take until June 2001 until there is enough comparable data available showing the real trends on the current usage of herbicides.
There are still some areas of the Weed Management Policy that have yet to be implemented pending the availability of sufficient funds. These include management of ‘natural areas’ - areas of native, exotic and mixed vegetation bush, wetlands, volcanic cones and grazed areas. “The greatest weed threat in and around Auckland City is the invasion of the few remaining bush remnants”, said Councillor Christian. Some of the more common invaders are wattle, monkey-apple, pine, tobacco weed, wandering jew, ginger and other species of vines. Tree privet is the major tree weed that threatens the bush.
The provision of this extra funding will allow weed control to progress on up to six sites simultaneously. Currently there are 41 sites listed as a high priority, 77 as medium and 489 as low priority areas.
further information please contact:
Councillor Bill Christian
Parks and Recreation Committee
Tel: 527 8648 or 025 814721