The Environment Risk Management Authority is seeking public comment on an application to import a fungus to nobble a particularly nasty pasture weed.
Marlborough District Council has applied to ERMA to release the Argentinian rust fungus to attack the weed, Chilean needlegrass.
Chilean needle grass is a threat to livestock, as well as people. It's difficult to control and produces barbed seeds that can penetrate animal hides and corkscrew their way into flesh and bone.
Marlborough has the worst needle grass problem with 3000 hectares infested. There are also pockets in Hawke's Bay and Auckland and about 80 hectares are infected in the Cheviot area of North Canterbury.
Landcare Research says it has tested the fungus extensively and believes it will successfully attack and reproduce on Chilean needlegrass without harming non-target species.
Public submissions on the application close on 9 May.