Authorities are trying to tackle an agricultural pest in Canterbury.
Chilean Needle Grass produces barbed seeds that can penetrate animal hides and corkscrew their way into flesh and bone.
It is most commonly found in Marlborough and Hawke's Bay, but was first found on a North Canterbury farm in 2008.
A resource manager for the Canterbury Regional Council says a recent spread of the tufted perennial plant to the Hurunui District has sparked a group of North Canterbury farmers into action to eradicate the weed.
Kim Drummond says the group's work could benefit other regions affected by Chilean Needle Grass.
