Dense weeds inundating the Raumanga Stream between Bernard Street footbridge and Otaika Road will soon be replaced by native vegetation as part of the Blue - Green Network Programme alongside the Raumanga Shared Path.
Raumanga Shared Path extension project
We plan to commence work on revitalising the Raumanga Stream beginning 19 February 2024, focusing on controlling Giant Reed (Arundo donax) on the northern stream bank and other pest plant species on the southern stream bank growing alongside the shared path.
Once the weeds are controlled, the area will be replanted with native vegetation to restore the riparian ecosystem by providing bank stability and riparian shade and shelter.
Shade is especially important as it helps to lower stream water temperatures, providing suitable conditions for in-stream life.
Leaf litter, small twigs and insects that fall into the stream from riparian plants provide an important food source for microbes and many species of aquatic invertebrates on which fish feed.
A staggered approach will be taken with specific areas of weed infestations and the first round of replanting will commence in July 2024.
Weed control and replanting is expected to be completed in June 2025.
Two years of maintenance will follow through to June 2027.
The protection and enhancement of indigenous biodiversity is at the core of Wildlands Consultants Ltd. Herbicides are an important tool in controlling pest plants at the site and restoring the Raumanga Stream margins.
Controlling pest plants by herbicide reduces the risk of erosion compared to hand or mechanical control, prevents targeted pest plants spreading further, and is effective so reduces the number of repeat treatments required on infestations.
The types of agrichemicals that may be used over the entire revitalisation period include:
- Glyphosate
- Triclopyr
- Metsulfuron
- Haloxyfop
- Clopyralid
- Organosilicone
Field staff will ensure best control methods for each pest plant infestation at the site are followed.
Agrichemical application will be in low volume, diluted correctly, targeted, and sprayed in a minimal concentration.
Further protective measures will be undertaken to reduce any environmental risks posed by herbicide use in line with NZS8409:2021.