People in the Waimakariri district are being warned to avoid going into or near any areas with trees because of dangerous, broken branches from last Tuesday's windstorm.
Waimakariri District Council Rural Fire Officer Tim Sheppard said a lot of the trees and branches were likely to snap without warning, and anyone going near the trees with a chainsaw was literally taking their life in their hands.
People were being asked to stay away from any forested areas and from beach access areas at Waikuku, Woodend and Pines Beach/Kairaki.
Meanwhile, Irrigation New Zealand chief executive Andrew Curtis urged Canterbury farmers about to restart irrigators following the storm to check them for lightning strike damage.
Lightning strike had emerged as a secondary cause of problems after hundreds of irrigation machines had were damaged by high winds last Tuesday night, Mr Curtis said.
There were reports of irrigation control systems being ruined by lightning strike, especially in the Canterbury foothills.
Mr Curtis said farmers needed to check their infrastructure carefully before the watering season started next month because replacement parts were at a premium.