Firefighters are battling a large scrub fire on both sides of State Highway 3, west of Whanganui.
The road was closed for a time to prevent visibility issues for drivers from the smoke but reopened about 1.30pm on Friday.
Fire and Emergency NZ shift manager Chris Dalton said firefighters were still fighting a fire in Kai Iwi that was burning on both sides of SH3.
It was a substantial fire initially but the bulk of the fire had been knocked back, he said.
Arborists from the Whanganui District Council were also in attendance to assist with dropping some of the trees, he said.