A total fire ban has been put in place across the Hawke's Bay and Gisborne regions.
The Eastern Regional Rural Fire Committee says forests, grass and scrub are tinder dry and hot conditions are forecast to continue.
Chairman Trevor Mitchell said call-outs to fires had been increasing, putting strain on firefighters.
He said in recent days there had been a fire which burned through nine hectares of olive trees, and a barn full of hay in Clive was lost to flames.
A house and about 25 hectares of avocados and grass in Mahanga were burnt on Sunday, and another house was lost in a fire in Hastings.
Mr Mitchell said a total fire ban was in place, meaning no outdoor fires without the written permission of the principal rural fire officer.
Further south, the Marlborough District Council has put a total fire ban in place in the area south of the Wairau River, including urban and rural areas.