Weed control
Surveying weeds in the river beds to
help prevent new invasions
Exotic weeds are being controlled over 33,000 ha of riverbed, to maintain and restore native plant communities and wildlife feeding and breeding habitat. Russell lupin, broom, gorse, wilding conifers and crack willow are key weed species that Project River Recovery targets in braided rivers. Highest priority is given to preventing weed invasion of the near pristine 'upper rivers' above the Basin's uppermost hydro lakes.
Project River Recovery runs an eradication programme for yellow tree lupin and buddleia in the upper Waitaki Basin. It also runs an ongoing surveillance programme to spot any new invasive weeds that could threaten braided rivers.
Project River Recovery also carries out research that aims to improve how weeds are managed in braided rivers. One recent trial tested the effectiveness of a new more environmentally-friendly herbicide for use on Russell lupins around waterways. A second trial examined the viability of Russell lupin seeds in relation to their stage of seed pod development when herbicide is applied, to determine whether our weed control operations can effectively be extended to later in the season. The results of both trials are currently being analysed.