Ground crews are today making their way up 2km of track into the bushland in Whakamarama to investigate a large scrub fire that reached up to 1 hectare yesterday afternoon.

Fire broke out in an area of bushland on the Te Tuhi Track Road around 2pm yesterday keeping firefighters busy for about five hours.

A helicopter with a monsoon bucket was called to put out a large bush fire in Whakamarama.

Initial reports to Northern Communications Fire Service were of a 200 square metre scrub fire, which escalated and spread to 1.5hectares.

Crews from Greerton, Omokoroa, Waihi and Katikati, including ground crews from the rural fire service, were called to the fire but struggled to gain access up the track.

A helicopter carrying a monsoon bucket was called to help extinguish the fire.

Omokoroa Chief Fire Officer Ian Blunt says a ground crew are heading back into the bush today to investigate and dampen down any hot spots.

He says there is no indication of the cause of the fire.

'We don't know at this stage.”

Ian says the fire started in an isolated area of bushland making it very difficult for firefighters who had to walk 2km into the bush to reach the fire.

'It was in amongst the bush on Department of Conservation land. It looked like there may have been a fire there three years ago.”

The ground crew made their way through the bush and cut out a helicopter pad allowing the chopper to land.

A nearby resident told SunLive yesterday it is the third time fires have been lit to burn off scrub in the area.

Firefighters were also called to a grass fire on Seaforth Road in Bowentown about 2.10pm.

Two appliances, one from Waihi Beach and one from Athenree attended.

The Waihi Beach and Athenree crew were later joined by a rural fire service vehicle and two appliances including a water tanker from Waihi.

Coastguard volunteers offered their boat for use although the fire was under control before it was required.

A third fire broke out closer to Tauranga, where three crews from Greerton Fire Station and two water tankers were called to an 80square metre bush fire in Ohauiti just after 3.30pm.

Western Bay of Plenty principal rural fire officer Barry Low says both fires could have been deliberately lit.

Investigations into the cause of the fire are being carried out, although he says there is always an increased fire risk around the start of summer.

All three fires are believed to have been under control by 6pm.