Fire crews were in attendance this morning at the incident, at Askwith Moor above the West Yorkshire market town.
In a tweet, North Yorkshire Fire & Rescue Service said: “One of our Harrogate crews is attending some controlled burning in the Askwith area.
“Due to the size of the fire and the windy conditions they’re standing by whilst the fire is extinguished.”
A spokeswoman for the North Yorkshire brigade said firefighters were called to the scene shortly after 10.30am.
An animal rights group called Ban Bloodsports on Yorkshire’s Moors has said it believes today's incident was linked to so-called ‘heather burning’ activity.
Gamekeepers in rural areas often manage the growth of moorland heather – which when kept short provides food for red grouse – by burning it in patches.
Luke Steele, from Ban Bloodsports on Yorkshire’s Moors, said: “Burning on grouse shooting estates is extremely damaging to both wildlife and the environment and disrupts otherwise peaceful life in local communities.”