The restoration effort at Grovetown Lagoon has primarily involved working on the eradication of weeds, and re-establishment of native vegetation.
Willows, the most predominant weed tree, are killed off gradually by drilling and injecting herbicide. Old man’s beard, hawthorn, elderberry, ivy, periwinkle, blackberry, honeysuckle and also other weeds including garden escapers are also targeted with weed killer, particularly at sites where planting been done so the natives can get established.Where weed eradication has been completed, then volunteers can set to and plant with plants suitable for riparian and wetland habitat e.g kowhai, cabbage trees, kahikatea, swamp maire, flax and sedges. Plants are grown from locally sourced seeds only.
Dead/dying willows are underplanted and used as shade and shelter for the young native plants. Gradually the margins of the lagoon are being transformed from predominantly willow forest to a mixture of native plants. One of the overall goals is to enable the establishment of a native plant ecosystem, thereby returning the lagoon towards it’s natural state. Native plantings will bring more birds to the area, which will be a bonus for the community when they visit.
The large swamp area adjacent to the northern lagoon outlet has the least modified wetland vegetation with a diverse mix of native sedges and herbs including the rare swamp nettle. This area has recently been purchased by Marlborough District Council and the inclusion of this area into the Grovetown Lagoon restoration project, and the continued restoration of this whole ecosystem will be a significant conservation gain for the district.