A magic bullet for the Northern Australian neem nightmare?

摘要

Planted as a shade tree in many Kimberley communities, neem (Azadirachta indica A.Juss), is now a highly invasive weed, harming the natural environment, agricultural production and cultural sites across the region and northern Australia. In 2013, neemwas ranked among the Kimberley's top environmental weeds, and voted the highest priority weed at the 2015 "Kimberley Weed Forum'. The Northern Territory lists neem as a Class B and Class C weed, yet it remains undeclared in Queensland and Western Australia. In 2017, Environs Kimberley developed the Interim Kimberley Neem Management Plan which, for the first time, collated Kimberley mapping data, presented case studies and made recommendations; including trialling new control technology and advocating for improved recognition of neem as a serious weed at a state and national level.Currently, Environs Kimberley is working with several groups to run experimental control trials, and Nyikina Mangala Rangers to undertake control and mapping of neem at Oongkalkada, an important cultural site. Control poses a wide range of challenges for land managers, including low efficacy of some treatment methods, cost of equipment and materials, labour intensity and occupational, health and safety risks in remote areas.The control method being trialled uses dry herbicide in capsules developed by Bioherbicides Australia. Previously with one option of control, operators might spend a day sweating it out with chainsaws and loppers to treat a relatively small area of neeminfestation. Use of the capsules could allow hundreds of trees to be treated per person per day at reduced cost and greatly improved human and environmental safety.